Add Slack support

59 files changed, 6107 insertions, 0 deletions

diff --git a/vendor/github.com/nlopes/slack/LICENSE b/vendor/github.com/nlopes/slack/LICENSE
new file mode 100644
index 00000000..5145171f
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/LICENSE
@@ -0,0 +1,23 @@
+Copyright (c) 2015, Norberto Lopes
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+this list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/nlopes/slack/admin.go b/vendor/github.com/nlopes/slack/admin.go
new file mode 100644
index 00000000..393b2880
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/admin.go
@@ -0,0 +1,190 @@
+package slack
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+)
+
+type adminResponse struct {
+	OK    bool   `json:"ok"`
+	Error string `json:"error"`
+}
+
+func adminRequest(method string, teamName string, values url.Values, debug bool) (*adminResponse, error) {
+	adminResponse := &adminResponse{}
+	err := parseAdminResponse(method, teamName, values, adminResponse, debug)
+	if err != nil {
+		return nil, err
+	}
+
+	if !adminResponse.OK {
+		return nil, errors.New(adminResponse.Error)
+	}
+
+	return adminResponse, nil
+}
+
+// DisableUser disabled a user account, given a user ID
+func (api *Client) DisableUser(teamName string, uid string) error {
+	values := url.Values{
+		"user":       {uid},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("setInactive", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to disable user with id '%s': %s", uid, err)
+	}
+
+	return nil
+}
+
+// InviteGuest invites a user to Slack as a single-channel guest
+func (api *Client) InviteGuest(
+	teamName string,
+	channel string,
+	firstName string,
+	lastName string,
+	emailAddress string,
+) error {
+	values := url.Values{
+		"email":            {emailAddress},
+		"channels":         {channel},
+		"first_name":       {firstName},
+		"last_name":        {lastName},
+		"ultra_restricted": {"1"},
+		"token":            {api.config.token},
+		"set_active":       {"true"},
+		"_attempts":        {"1"},
+	}
+
+	_, err := adminRequest("invite", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to invite single-channel guest: %s", err)
+	}
+
+	return nil
+}
+
+// InviteRestricted invites a user to Slack as a restricted account
+func (api *Client) InviteRestricted(
+	teamName string,
+	channel string,
+	firstName string,
+	lastName string,
+	emailAddress string,
+) error {
+	values := url.Values{
+		"email":      {emailAddress},
+		"channels":   {channel},
+		"first_name": {firstName},
+		"last_name":  {lastName},
+		"restricted": {"1"},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("invite", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to restricted account: %s", err)
+	}
+
+	return nil
+}
+
+// InviteToTeam invites a user to a Slack team
+func (api *Client) InviteToTeam(
+	teamName string,
+	firstName string,
+	lastName string,
+	emailAddress string,
+) error {
+	values := url.Values{
+		"email":      {emailAddress},
+		"first_name": {firstName},
+		"last_name":  {lastName},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("invite", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to invite to team: %s", err)
+	}
+
+	return nil
+}
+
+// SetRegular enables the specified user
+func (api *Client) SetRegular(teamName string, user string) error {
+	values := url.Values{
+		"user":       {user},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("setRegular", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to change the user (%s) to a regular user: %s", user, err)
+	}
+
+	return nil
+}
+
+// SendSSOBindingEmail sends an SSO binding email to the specified user
+func (api *Client) SendSSOBindingEmail(teamName string, user string) error {
+	values := url.Values{
+		"user":       {user},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("sendSSOBind", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to send SSO binding email for user (%s): %s", user, err)
+	}
+
+	return nil
+}
+
+// SetUltraRestricted converts a user into a single-channel guest
+func (api *Client) SetUltraRestricted(teamName, uid, channel string) error {
+	values := url.Values{
+		"user":       {uid},
+		"channel":    {channel},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("setUltraRestricted", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to ultra-restrict account: %s", err)
+	}
+
+	return nil
+}
+
+// SetRestricted converts a user into a restricted account
+func (api *Client) SetRestricted(teamName, uid string) error {
+	values := url.Values{
+		"user":       {uid},
+		"token":      {api.config.token},
+		"set_active": {"true"},
+		"_attempts":  {"1"},
+	}
+
+	_, err := adminRequest("setRestricted", teamName, values, api.debug)
+	if err != nil {
+		return fmt.Errorf("Failed to restrict account: %s", err)
+	}
+
+	return nil
+}
diff --git a/vendor/github.com/nlopes/slack/attachments.go b/vendor/github.com/nlopes/slack/attachments.go
new file mode 100644
index 00000000..4faf3e3f
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/attachments.go
@@ -0,0 +1,76 @@
+package slack
+
+// AttachmentField contains information for an attachment field
+// An Attachment can contain multiple of these
+type AttachmentField struct {
+	Title string `json:"title"`
+	Value string `json:"value"`
+	Short bool   `json:"short"`
+}
+
+// AttachmentAction is a button to be included in the attachment. Required when
+// using message buttons and otherwise not useful. A maximum of 5 actions may be
+// provided per attachment.
+type AttachmentAction struct {
+	Name    string              `json:"name"`              // Required.
+	Text    string              `json:"text"`              // Required.
+	Style   string              `json:"style,omitempty"`   // Optional. Allowed values: "default", "primary", "danger"
+	Type    string              `json:"type"`              // Required. Must be set to "button"
+	Value   string              `json:"value,omitempty"`   // Optional.
+	Confirm []ConfirmationField `json:"confirm,omitempty"` // Optional.
+}
+
+// AttachmentActionCallback is sent from Slack when a user clicks a button in an interactive message (aka AttachmentAction)
+type AttachmentActionCallback struct {
+	Actions    []AttachmentAction `json:"actions"`
+	CallbackID string             `json:"callback_id"`
+	Team       Team               `json:"team"`
+	Channel    Channel            `json:"channel"`
+	User       User               `json:"user"`
+
+	OriginalMessage Message `json:"original_message"`
+
+	ActionTs     string `json:"action_ts"`
+	MessageTs    string `json:"message_ts"`
+	AttachmentID string `json:"attachment_id"`
+	Token        string `json:"token"`
+	ResponseURL  string `json:"response_url"`
+}
+
+// ConfirmationField are used to ask users to confirm actions
+type ConfirmationField struct {
+	Title       string `json:"title,omitempty"`        // Optional.
+	Text        string `json:"text"`                   // Required.
+	OkText      string `json:"ok_text,omitempty"`      // Optional. Defaults to "Okay"
+	DismissText string `json:"dismiss_text,omitempty"` // Optional. Defaults to "Cancel"
+}
+
+// Attachment contains all the information for an attachment
+type Attachment struct {
+	Color    string `json:"color,omitempty"`
+	Fallback string `json:"fallback"`
+
+	CallbackID string `json:"callback_id,omitempty"`
+
+	AuthorName    string `json:"author_name,omitempty"`
+	AuthorSubname string `json:"author_subname,omitempty"`
+	AuthorLink    string `json:"author_link,omitempty"`
+	AuthorIcon    string `json:"author_icon,omitempty"`
+
+	Title     string `json:"title,omitempty"`
+	TitleLink string `json:"title_link,omitempty"`
+	Pretext   string `json:"pretext,omitempty"`
+	Text      string `json:"text"`
+
+	ImageURL string `json:"image_url,omitempty"`
+	ThumbURL string `json:"thumb_url,omitempty"`
+
+	Fields     []AttachmentField  `json:"fields,omitempty"`
+	Actions    []AttachmentAction `json:"actions,omitempty"`
+	MarkdownIn []string           `json:"mrkdwn_in,omitempty"`
+
+	Footer     string `json:"footer,omitempty"`
+	FooterIcon string `json:"footer_icon,omitempty"`
+
+	Ts int64 `json:"ts,omitempty"`
+}
diff --git a/vendor/github.com/nlopes/slack/backoff.go b/vendor/github.com/nlopes/slack/backoff.go
new file mode 100644
index 00000000..e555a1ad
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/backoff.go
@@ -0,0 +1,57 @@
+package slack
+
+import (
+	"math"
+	"math/rand"
+	"time"
+)
+
+// This one was ripped from https://github.com/jpillora/backoff/blob/master/backoff.go
+
+// Backoff is a time.Duration counter. It starts at Min.  After every
+// call to Duration() it is multiplied by Factor.  It is capped at
+// Max. It returns to Min on every call to Reset().  Used in
+// conjunction with the time package.
+type backoff struct {
+	attempts int
+	//Factor is the multiplying factor for each increment step
+	Factor float64
+	//Jitter eases contention by randomizing backoff steps
+	Jitter bool
+	//Min and Max are the minimum and maximum values of the counter
+	Min, Max time.Duration
+}
+
+// Returns the current value of the counter and then multiplies it
+// Factor
+func (b *backoff) Duration() time.Duration {
+	//Zero-values are nonsensical, so we use
+	//them to apply defaults
+	if b.Min == 0 {
+		b.Min = 100 * time.Millisecond
+	}
+	if b.Max == 0 {
+		b.Max = 10 * time.Second
+	}
+	if b.Factor == 0 {
+		b.Factor = 2
+	}
+	//calculate this duration
+	dur := float64(b.Min) * math.Pow(b.Factor, float64(b.attempts))
+	if b.Jitter == true {
+		dur = rand.Float64()*(dur-float64(b.Min)) + float64(b.Min)
+	}
+	//cap!
+	if dur > float64(b.Max) {
+		return b.Max
+	}
+	//bump attempts count
+	b.attempts++
+	//return as a time.Duration
+	return time.Duration(dur)
+}
+
+//Resets the current value of the counter back to Min
+func (b *backoff) Reset() {
+	b.attempts = 0
+}
diff --git a/vendor/github.com/nlopes/slack/channels.go b/vendor/github.com/nlopes/slack/channels.go
new file mode 100644
index 00000000..05cfbe1d
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/channels.go
@@ -0,0 +1,261 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+type channelResponseFull struct {
+	Channel      Channel   `json:"channel"`
+	Channels     []Channel `json:"channels"`
+	Purpose      string    `json:"purpose"`
+	Topic        string    `json:"topic"`
+	NotInChannel bool      `json:"not_in_channel"`
+	History
+	SlackResponse
+}
+
+// Channel contains information about the channel
+type Channel struct {
+	groupConversation
+	IsChannel bool `json:"is_channel"`
+	IsGeneral bool `json:"is_general"`
+	IsMember  bool `json:"is_member"`
+}
+
+func channelRequest(path string, values url.Values, debug bool) (*channelResponseFull, error) {
+	response := &channelResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// ArchiveChannel archives the given channel
+func (api *Client) ArchiveChannel(channel string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	_, err := channelRequest("channels.archive", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// UnarchiveChannel unarchives the given channel
+func (api *Client) UnarchiveChannel(channel string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	_, err := channelRequest("channels.unarchive", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// CreateChannel creates a channel with the given name and returns a *Channel
+func (api *Client) CreateChannel(channel string) (*Channel, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"name":  {channel},
+	}
+	response, err := channelRequest("channels.create", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+}
+
+// GetChannelHistory retrieves the channel history
+func (api *Client) GetChannelHistory(channel string, params HistoryParameters) (*History, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	if params.Latest != DEFAULT_HISTORY_LATEST {
+		values.Add("latest", params.Latest)
+	}
+	if params.Oldest != DEFAULT_HISTORY_OLDEST {
+		values.Add("oldest", params.Oldest)
+	}
+	if params.Count != DEFAULT_HISTORY_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Inclusive != DEFAULT_HISTORY_INCLUSIVE {
+		if params.Inclusive {
+			values.Add("inclusive", "1")
+		} else {
+			values.Add("inclusive", "0")
+		}
+	}
+	if params.Unreads != DEFAULT_HISTORY_UNREADS {
+		if params.Unreads {
+			values.Add("unreads", "1")
+		} else {
+			values.Add("unreads", "0")
+		}
+	}
+	response, err := channelRequest("channels.history", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.History, nil
+}
+
+// GetChannelInfo retrieves the given channel
+func (api *Client) GetChannelInfo(channel string) (*Channel, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	response, err := channelRequest("channels.info", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+}
+
+// InviteUserToChannel invites a user to a given channel and returns a *Channel
+func (api *Client) InviteUserToChannel(channel, user string) (*Channel, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"user":    {user},
+	}
+	response, err := channelRequest("channels.invite", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+}
+
+// JoinChannel joins the currently authenticated user to a channel
+func (api *Client) JoinChannel(channel string) (*Channel, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"name":  {channel},
+	}
+	response, err := channelRequest("channels.join", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+}
+
+// LeaveChannel makes the authenticated user leave the given channel
+func (api *Client) LeaveChannel(channel string) (bool, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	response, err := channelRequest("channels.leave", values, api.debug)
+	if err != nil {
+		return false, err
+	}
+	if response.NotInChannel {
+		return response.NotInChannel, nil
+	}
+	return false, nil
+}
+
+// KickUserFromChannel kicks a user from a given channel
+func (api *Client) KickUserFromChannel(channel, user string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"user":    {user},
+	}
+	_, err := channelRequest("channels.kick", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// GetChannels retrieves all the channels
+func (api *Client) GetChannels(excludeArchived bool) ([]Channel, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if excludeArchived {
+		values.Add("exclude_archived", "1")
+	}
+	response, err := channelRequest("channels.list", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.Channels, nil
+}
+
+// SetChannelReadMark sets the read mark of a given channel to a specific point
+// Clients should try to avoid making this call too often. When needing to mark a read position, a client should set a
+// timer before making the call. In this way, any further updates needed during the timeout will not generate extra calls
+// (just one per channel). This is useful for when reading scroll-back history, or following a busy live channel. A
+// timeout of 5 seconds is a good starting point. Be sure to flush these calls on shutdown/logout.
+func (api *Client) SetChannelReadMark(channel, ts string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"ts":      {ts},
+	}
+	_, err := channelRequest("channels.mark", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// RenameChannel renames a given channel
+func (api *Client) RenameChannel(channel, name string) (*Channel, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"name":    {name},
+	}
+	// XXX: the created entry in this call returns a string instead of a number
+	// so I may have to do some workaround to solve it.
+	response, err := channelRequest("channels.rename", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+
+}
+
+// SetChannelPurpose sets the channel purpose and returns the purpose that was
+// successfully set
+func (api *Client) SetChannelPurpose(channel, purpose string) (string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"purpose": {purpose},
+	}
+	response, err := channelRequest("channels.setPurpose", values, api.debug)
+	if err != nil {
+		return "", err
+	}
+	return response.Purpose, nil
+}
+
+// SetChannelTopic sets the channel topic and returns the topic that was successfully set
+func (api *Client) SetChannelTopic(channel, topic string) (string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"topic":   {topic},
+	}
+	response, err := channelRequest("channels.setTopic", values, api.debug)
+	if err != nil {
+		return "", err
+	}
+	return response.Topic, nil
+}
diff --git a/vendor/github.com/nlopes/slack/chat.go b/vendor/github.com/nlopes/slack/chat.go
new file mode 100644
index 00000000..52a3420f
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/chat.go
@@ -0,0 +1,166 @@
+package slack
+
+import (
+	"encoding/json"
+	"errors"
+	"net/url"
+	"strings"
+)
+
+const (
+	DEFAULT_MESSAGE_USERNAME     = ""
+	DEFAULT_MESSAGE_ASUSER       = false
+	DEFAULT_MESSAGE_PARSE        = ""
+	DEFAULT_MESSAGE_LINK_NAMES   = 0
+	DEFAULT_MESSAGE_UNFURL_LINKS = false
+	DEFAULT_MESSAGE_UNFURL_MEDIA = true
+	DEFAULT_MESSAGE_ICON_URL     = ""
+	DEFAULT_MESSAGE_ICON_EMOJI   = ""
+	DEFAULT_MESSAGE_MARKDOWN     = true
+	DEFAULT_MESSAGE_ESCAPE_TEXT  = true
+)
+
+type chatResponseFull struct {
+	Channel   string `json:"channel"`
+	Timestamp string `json:"ts"`
+	Text      string `json:"text"`
+	SlackResponse
+}
+
+// PostMessageParameters contains all the parameters necessary (including the optional ones) for a PostMessage() request
+type PostMessageParameters struct {
+	Text        string
+	Username    string
+	AsUser      bool
+	Parse       string
+	LinkNames   int
+	Attachments []Attachment
+	UnfurlLinks bool
+	UnfurlMedia bool
+	IconURL     string
+	IconEmoji   string
+	Markdown    bool `json:"mrkdwn,omitempty"`
+	EscapeText  bool
+}
+
+// NewPostMessageParameters provides an instance of PostMessageParameters with all the sane default values set
+func NewPostMessageParameters() PostMessageParameters {
+	return PostMessageParameters{
+		Username:    DEFAULT_MESSAGE_USERNAME,
+		AsUser:      DEFAULT_MESSAGE_ASUSER,
+		Parse:       DEFAULT_MESSAGE_PARSE,
+		LinkNames:   DEFAULT_MESSAGE_LINK_NAMES,
+		Attachments: nil,
+		UnfurlLinks: DEFAULT_MESSAGE_UNFURL_LINKS,
+		UnfurlMedia: DEFAULT_MESSAGE_UNFURL_MEDIA,
+		IconURL:     DEFAULT_MESSAGE_ICON_URL,
+		IconEmoji:   DEFAULT_MESSAGE_ICON_EMOJI,
+		Markdown:    DEFAULT_MESSAGE_MARKDOWN,
+		EscapeText:  DEFAULT_MESSAGE_ESCAPE_TEXT,
+	}
+}
+
+func chatRequest(path string, values url.Values, debug bool) (*chatResponseFull, error) {
+	response := &chatResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// DeleteMessage deletes a message in a channel
+func (api *Client) DeleteMessage(channel, messageTimestamp string) (string, string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"ts":      {messageTimestamp},
+	}
+	response, err := chatRequest("chat.delete", values, api.debug)
+	if err != nil {
+		return "", "", err
+	}
+	return response.Channel, response.Timestamp, nil
+}
+
+func escapeMessage(message string) string {
+	replacer := strings.NewReplacer("&", "&amp;", "<", "&lt;", ">", "&gt;")
+	return replacer.Replace(message)
+}
+
+// PostMessage sends a message to a channel.
+// Message is escaped by default according to https://api.slack.com/docs/formatting
+// Use http://davestevens.github.io/slack-message-builder/ to help crafting your message.
+func (api *Client) PostMessage(channel, text string, params PostMessageParameters) (string, string, error) {
+	if params.EscapeText {
+		text = escapeMessage(text)
+	}
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"text":    {text},
+	}
+	if params.Username != DEFAULT_MESSAGE_USERNAME {
+		values.Set("username", string(params.Username))
+	}
+	if params.AsUser != DEFAULT_MESSAGE_ASUSER {
+		values.Set("as_user", "true")
+	}
+	if params.Parse != DEFAULT_MESSAGE_PARSE {
+		values.Set("parse", string(params.Parse))
+	}
+	if params.LinkNames != DEFAULT_MESSAGE_LINK_NAMES {
+		values.Set("link_names", "1")
+	}
+	if params.Attachments != nil {
+		attachments, err := json.Marshal(params.Attachments)
+		if err != nil {
+			return "", "", err
+		}
+		values.Set("attachments", string(attachments))
+	}
+	if params.UnfurlLinks != DEFAULT_MESSAGE_UNFURL_LINKS {
+		values.Set("unfurl_links", "true")
+	}
+	// I want to send a message with explicit `as_user` `true` and `unfurl_links` `false` in request.
+	// Because setting `as_user` to `true` will change the default value for `unfurl_links` to `true` on Slack API side.
+	if params.AsUser != DEFAULT_MESSAGE_ASUSER && params.UnfurlLinks == DEFAULT_MESSAGE_UNFURL_LINKS {
+		values.Set("unfurl_links", "false")
+	}
+	if params.UnfurlMedia != DEFAULT_MESSAGE_UNFURL_MEDIA {
+		values.Set("unfurl_media", "false")
+	}
+	if params.IconURL != DEFAULT_MESSAGE_ICON_URL {
+		values.Set("icon_url", params.IconURL)
+	}
+	if params.IconEmoji != DEFAULT_MESSAGE_ICON_EMOJI {
+		values.Set("icon_emoji", params.IconEmoji)
+	}
+	if params.Markdown != DEFAULT_MESSAGE_MARKDOWN {
+		values.Set("mrkdwn", "false")
+	}
+
+	response, err := chatRequest("chat.postMessage", values, api.debug)
+	if err != nil {
+		return "", "", err
+	}
+	return response.Channel, response.Timestamp, nil
+}
+
+// UpdateMessage updates a message in a channel
+func (api *Client) UpdateMessage(channel, timestamp, text string) (string, string, string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"text":    {escapeMessage(text)},
+		"ts":      {timestamp},
+	}
+	response, err := chatRequest("chat.update", values, api.debug)
+	if err != nil {
+		return "", "", "", err
+	}
+	return response.Channel, response.Timestamp, response.Text, nil
+}
diff --git a/vendor/github.com/nlopes/slack/comment.go b/vendor/github.com/nlopes/slack/comment.go
new file mode 100644
index 00000000..7d1c0d4e
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/comment.go
@@ -0,0 +1,10 @@
+package slack
+
+// Comment contains all the information relative to a comment
+type Comment struct {
+	ID        string   `json:"id,omitempty"`
+	Created   JSONTime `json:"created,omitempty"`
+	Timestamp JSONTime `json:"timestamp,omitempty"`
+	User      string   `json:"user,omitempty"`
+	Comment   string   `json:"comment,omitempty"`
+}
diff --git a/vendor/github.com/nlopes/slack/conversation.go b/vendor/github.com/nlopes/slack/conversation.go
new file mode 100644
index 00000000..51b993d1
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/conversation.go
@@ -0,0 +1,38 @@
+package slack
+
+// Conversation is the foundation for IM and BaseGroupConversation
+type conversation struct {
+	ID                 string   `json:"id"`
+	Created            JSONTime `json:"created"`
+	IsOpen             bool     `json:"is_open"`
+	LastRead           string   `json:"last_read,omitempty"`
+	Latest             *Message `json:"latest,omitempty"`
+	UnreadCount        int      `json:"unread_count,omitempty"`
+	UnreadCountDisplay int      `json:"unread_count_display,omitempty"`
+}
+
+// GroupConversation is the foundation for Group and Channel
+type groupConversation struct {
+	conversation
+	Name       string   `json:"name"`
+	Creator    string   `json:"creator"`
+	IsArchived bool     `json:"is_archived"`
+	Members    []string `json:"members"`
+	NumMembers int      `json:"num_members,omitempty"`
+	Topic      Topic    `json:"topic"`
+	Purpose    Purpose  `json:"purpose"`
+}
+
+// Topic contains information about the topic
+type Topic struct {
+	Value   string   `json:"value"`
+	Creator string   `json:"creator"`
+	LastSet JSONTime `json:"last_set"`
+}
+
+// Purpose contains information about the purpose
+type Purpose struct {
+	Value   string   `json:"value"`
+	Creator string   `json:"creator"`
+	LastSet JSONTime `json:"last_set"`
+}
diff --git a/vendor/github.com/nlopes/slack/dnd.go b/vendor/github.com/nlopes/slack/dnd.go
new file mode 100644
index 00000000..ac87758d
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/dnd.go
@@ -0,0 +1,123 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+type SnoozeDebug struct {
+	SnoozeEndDate string `json:"snooze_end_date"`
+}
+
+type SnoozeInfo struct {
+	SnoozeEnabled   bool        `json:"snooze_enabled,omitempty"`
+	SnoozeEndTime   int         `json:"snooze_endtime,omitempty"`
+	SnoozeRemaining int         `json:"snooze_remaining,omitempty"`
+	SnoozeDebug     SnoozeDebug `json:"snooze_debug,omitempty"`
+}
+
+type DNDStatus struct {
+	Enabled            bool `json:"dnd_enabled"`
+	NextStartTimestamp int  `json:"next_dnd_start_ts"`
+	NextEndTimestamp   int  `json:"next_dnd_end_ts"`
+	SnoozeInfo
+}
+
+type dndResponseFull struct {
+	DNDStatus
+	SlackResponse
+}
+
+type dndTeamInfoResponse struct {
+	Users map[string]DNDStatus `json:"users"`
+	SlackResponse
+}
+
+func dndRequest(path string, values url.Values, debug bool) (*dndResponseFull, error) {
+	response := &dndResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// EndDND ends the user's scheduled Do Not Disturb session
+func (api *Client) EndDND() error {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+
+	response := &SlackResponse{}
+	if err := post("dnd.endDnd", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// EndSnooze ends the current user's snooze mode
+func (api *Client) EndSnooze() (*DNDStatus, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+
+	response, err := dndRequest("dnd.endSnooze", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.DNDStatus, nil
+}
+
+// GetDNDInfo provides information about a user's current Do Not Disturb settings.
+func (api *Client) GetDNDInfo(user *string) (*DNDStatus, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if user != nil {
+		values.Set("user", *user)
+	}
+	response, err := dndRequest("dnd.info", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.DNDStatus, nil
+}
+
+// GetDNDTeamInfo provides information about a user's current Do Not Disturb settings.
+func (api *Client) GetDNDTeamInfo(users []string) (map[string]DNDStatus, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"users": {strings.Join(users, ",")},
+	}
+	response := &dndTeamInfoResponse{}
+	if err := post("dnd.teamInfo", values, response, api.debug); err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response.Users, nil
+}
+
+// SetSnooze adjusts the snooze duration for a user's Do Not Disturb
+// settings. If a snooze session is not already active for the user, invoking
+// this method will begin one for the specified duration.
+func (api *Client) SetSnooze(minutes int) (*DNDStatus, error) {
+	values := url.Values{
+		"token":       {api.config.token},
+		"num_minutes": {strconv.Itoa(minutes)},
+	}
+	response, err := dndRequest("dnd.setSnooze", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.DNDStatus, nil
+}
diff --git a/vendor/github.com/nlopes/slack/emoji.go b/vendor/github.com/nlopes/slack/emoji.go
new file mode 100644
index 00000000..776c4a5f
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/emoji.go
@@ -0,0 +1,27 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+)
+
+type emojiResponseFull struct {
+	Emoji map[string]string `json:"emoji"`
+	SlackResponse
+}
+
+// GetEmoji retrieves all the emojis
+func (api *Client) GetEmoji() (map[string]string, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	response := &emojiResponseFull{}
+	err := post("emoji.list", values, response, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response.Emoji, nil
+}
diff --git a/vendor/github.com/nlopes/slack/examples/channels/channels.go b/vendor/github.com/nlopes/slack/examples/channels/channels.go
new file mode 100644
index 00000000..a4465bdb
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/channels/channels.go
@@ -0,0 +1,19 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR_TOKEN_HERE")
+	channels, err := api.GetChannels(false)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	for _, channel := range channels {
+		fmt.Println(channel.ID)
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/examples/files/files.go b/vendor/github.com/nlopes/slack/examples/files/files.go
new file mode 100644
index 00000000..bb7b4e50
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/files/files.go
@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR_TOKEN_HERE")
+	params := slack.FileUploadParameters{
+		Title: "Batman Example",
+		//Filetype: "txt",
+		File: "example.txt",
+		//Content:  "Nan Nan Nan Nan Nan Nan Nan Nan Batman",
+	}
+	file, err := api.UploadFile(params)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	fmt.Printf("Name: %s, URL: %s\n", file.Name, file.URL)
+
+	err = api.DeleteFile(file.ID)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	fmt.Printf("File %s deleted successfully.\n", file.Name)
+}
diff --git a/vendor/github.com/nlopes/slack/examples/groups/groups.go b/vendor/github.com/nlopes/slack/examples/groups/groups.go
new file mode 100644
index 00000000..2af215d1
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/groups/groups.go
@@ -0,0 +1,22 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR_TOKEN_HERE")
+	// If you set debugging, it will log all requests to the console
+	// Useful when encountering issues
+	// api.SetDebug(true)
+	groups, err := api.GetGroups(false)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	for _, group := range groups {
+		fmt.Printf("ID: %s, Name: %s\n", group.ID, group.Name)
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/examples/messages/messages.go b/vendor/github.com/nlopes/slack/examples/messages/messages.go
new file mode 100644
index 00000000..b3ea87f3
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/messages/messages.go
@@ -0,0 +1,32 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR_TOKEN_HERE")
+	params := slack.PostMessageParameters{}
+	attachment := slack.Attachment{
+		Pretext: "some pretext",
+		Text:    "some text",
+		// Uncomment the following part to send a field too
+		/*
+			Fields: []slack.AttachmentField{
+				slack.AttachmentField{
+					Title: "a",
+					Value: "no",
+				},
+			},
+		*/
+	}
+	params.Attachments = []slack.Attachment{attachment}
+	channelID, timestamp, err := api.PostMessage("CHANNEL_ID", "Some text", params)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	fmt.Printf("Message successfully sent to channel %s at %s", channelID, timestamp)
+}
diff --git a/vendor/github.com/nlopes/slack/examples/pins/pins.go b/vendor/github.com/nlopes/slack/examples/pins/pins.go
new file mode 100644
index 00000000..d225184c
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/pins/pins.go
@@ -0,0 +1,123 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+/*
+   WARNING: This example is destructive in the sense that it create a channel called testpinning
+*/
+func main() {
+	var (
+		apiToken string
+		debug    bool
+	)
+
+	flag.StringVar(&apiToken, "token", "YOUR_TOKEN_HERE", "Your Slack API Token")
+	flag.BoolVar(&debug, "debug", false, "Show JSON output")
+	flag.Parse()
+
+	api := slack.New(apiToken)
+	if debug {
+		api.SetDebug(true)
+	}
+
+	var (
+		postAsUserName  string
+		postAsUserID    string
+		postToChannelID string
+	)
+
+	// Find the user to post as.
+	authTest, err := api.AuthTest()
+	if err != nil {
+		fmt.Printf("Error getting channels: %s\n", err)
+		return
+	}
+
+	channelName := "testpinning"
+
+	// Post as the authenticated user.
+	postAsUserName = authTest.User
+	postAsUserID = authTest.UserID
+
+	// Create a temporary channel
+	channel, err := api.CreateChannel(channelName)
+
+	if err != nil {
+		// If the channel exists, that means we just need to unarchive it
+		if err.Error() == "name_taken" {
+			err = nil
+			channels, err := api.GetChannels(false)
+			if err != nil {
+				fmt.Println("Could not retrieve channels")
+				return
+			}
+			for _, archivedChannel := range channels {
+				if archivedChannel.Name == channelName {
+					if archivedChannel.IsArchived {
+						err = api.UnarchiveChannel(archivedChannel.ID)
+						if err != nil {
+							fmt.Printf("Could not unarchive %s: %s\n", archivedChannel.ID, err)
+							return
+						}
+					}
+					channel = &archivedChannel
+					break
+				}
+			}
+		}
+		if err != nil {
+			fmt.Printf("Error setting test channel for pinning: %s\n", err)
+			return
+		}
+	}
+	postToChannelID = channel.ID
+
+	fmt.Printf("Posting as %s (%s) in channel %s\n", postAsUserName, postAsUserID, postToChannelID)
+
+	// Post a message.
+	postParams := slack.PostMessageParameters{}
+	channelID, timestamp, err := api.PostMessage(postToChannelID, "Is this any good?", postParams)
+	if err != nil {
+		fmt.Printf("Error posting message: %s\n", err)
+		return
+	}
+
+	// Grab a reference to the message.
+	msgRef := slack.NewRefToMessage(channelID, timestamp)
+
+	// Add message pin to channel
+	if err := api.AddPin(channelID, msgRef); err != nil {
+		fmt.Printf("Error adding pin: %s\n", err)
+		return
+	}
+
+	// List all of the users pins.
+	listPins, _, err := api.ListPins(channelID)
+	if err != nil {
+		fmt.Printf("Error listing pins: %s\n", err)
+		return
+	}
+	fmt.Printf("\n")
+	fmt.Printf("All pins by %s...\n", authTest.User)
+	for _, item := range listPins {
+		fmt.Printf(" > Item type: %s\n", item.Type)
+	}
+
+	// Remove the pin.
+	err = api.RemovePin(channelID, msgRef)
+	if err != nil {
+		fmt.Printf("Error remove pin: %s\n", err)
+		return
+	}
+
+	if err = api.ArchiveChannel(channelID); err != nil {
+		fmt.Printf("Error archiving channel: %s\n", err)
+		return
+	}
+
+}
diff --git a/vendor/github.com/nlopes/slack/examples/reactions/reactions.go b/vendor/github.com/nlopes/slack/examples/reactions/reactions.go
new file mode 100644
index 00000000..753f0d25
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/reactions/reactions.go
@@ -0,0 +1,126 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	var (
+		apiToken string
+		debug    bool
+	)
+
+	flag.StringVar(&apiToken, "token", "YOUR_TOKEN_HERE", "Your Slack API Token")
+	flag.BoolVar(&debug, "debug", false, "Show JSON output")
+	flag.Parse()
+
+	api := slack.New(apiToken)
+	if debug {
+		api.SetDebug(true)
+	}
+
+	var (
+		postAsUserName  string
+		postAsUserID    string
+		postToUserName  string
+		postToUserID    string
+		postToChannelID string
+	)
+
+	// Find the user to post as.
+	authTest, err := api.AuthTest()
+	if err != nil {
+		fmt.Printf("Error getting channels: %s\n", err)
+		return
+	}
+
+	// Post as the authenticated user.
+	postAsUserName = authTest.User
+	postAsUserID = authTest.UserID
+
+	// Posting to DM with self causes a conversation with slackbot.
+	postToUserName = authTest.User
+	postToUserID = authTest.UserID
+
+	// Find the channel.
+	_, _, chanID, err := api.OpenIMChannel(postToUserID)
+	if err != nil {
+		fmt.Printf("Error opening IM: %s\n", err)
+		return
+	}
+	postToChannelID = chanID
+
+	fmt.Printf("Posting as %s (%s) in DM with %s (%s), channel %s\n", postAsUserName, postAsUserID, postToUserName, postToUserID, postToChannelID)
+
+	// Post a message.
+	postParams := slack.PostMessageParameters{}
+	channelID, timestamp, err := api.PostMessage(postToChannelID, "Is this any good?", postParams)
+	if err != nil {
+		fmt.Printf("Error posting message: %s\n", err)
+		return
+	}
+
+	// Grab a reference to the message.
+	msgRef := slack.NewRefToMessage(channelID, timestamp)
+
+	// React with :+1:
+	if err := api.AddReaction("+1", msgRef); err != nil {
+		fmt.Printf("Error adding reaction: %s\n", err)
+		return
+	}
+
+	// React with :-1:
+	if err := api.AddReaction("cry", msgRef); err != nil {
+		fmt.Printf("Error adding reaction: %s\n", err)
+		return
+	}
+
+	// Get all reactions on the message.
+	msgReactions, err := api.GetReactions(msgRef, slack.NewGetReactionsParameters())
+	if err != nil {
+		fmt.Printf("Error getting reactions: %s\n", err)
+		return
+	}
+	fmt.Printf("\n")
+	fmt.Printf("%d reactions to message...\n", len(msgReactions))
+	for _, r := range msgReactions {
+		fmt.Printf("  %d users say %s\n", r.Count, r.Name)
+	}
+
+	// List all of the users reactions.
+	listReactions, _, err := api.ListReactions(slack.NewListReactionsParameters())
+	if err != nil {
+		fmt.Printf("Error listing reactions: %s\n", err)
+		return
+	}
+	fmt.Printf("\n")
+	fmt.Printf("All reactions by %s...\n", authTest.User)
+	for _, item := range listReactions {
+		fmt.Printf("%d on a %s...\n", len(item.Reactions), item.Type)
+		for _, r := range item.Reactions {
+			fmt.Printf("  %s (along with %d others)\n", r.Name, r.Count-1)
+		}
+	}
+
+	// Remove the :cry: reaction.
+	err = api.RemoveReaction("cry", msgRef)
+	if err != nil {
+		fmt.Printf("Error remove reaction: %s\n", err)
+		return
+	}
+
+	// Get all reactions on the message.
+	msgReactions, err = api.GetReactions(msgRef, slack.NewGetReactionsParameters())
+	if err != nil {
+		fmt.Printf("Error getting reactions: %s\n", err)
+		return
+	}
+	fmt.Printf("\n")
+	fmt.Printf("%d reactions to message after removing cry...\n", len(msgReactions))
+	for _, r := range msgReactions {
+		fmt.Printf("  %d users say %s\n", r.Count, r.Name)
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/examples/stars/stars.go b/vendor/github.com/nlopes/slack/examples/stars/stars.go
new file mode 100644
index 00000000..d20c3dcf
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/stars/stars.go
@@ -0,0 +1,46 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	var (
+		apiToken string
+		debug    bool
+	)
+
+	flag.StringVar(&apiToken, "token", "YOUR_TOKEN_HERE", "Your Slack API Token")
+	flag.BoolVar(&debug, "debug", false, "Show JSON output")
+	flag.Parse()
+
+	api := slack.New(apiToken)
+	if debug {
+		api.SetDebug(true)
+	}
+
+	// Get all stars for the usr.
+	params := slack.NewStarsParameters()
+	starredItems, _, err := api.GetStarred(params)
+	if err != nil {
+		fmt.Printf("Error getting stars: %s\n", err)
+		return
+	}
+	for _, s := range starredItems {
+		var desc string
+		switch s.Type {
+		case slack.TYPE_MESSAGE:
+			desc = s.Message.Text
+		case slack.TYPE_FILE:
+			desc = s.File.Name
+		case slack.TYPE_FILE_COMMENT:
+			desc = s.File.Name + " - " + s.Comment.Comment
+		case slack.TYPE_CHANNEL, slack.TYPE_IM, slack.TYPE_GROUP:
+			desc = s.Channel
+		}
+		fmt.Printf("Starred %s: %s\n", s.Type, desc)
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/examples/users/users.go b/vendor/github.com/nlopes/slack/examples/users/users.go
new file mode 100644
index 00000000..9a6e1f6f
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/users/users.go
@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR_TOKEN_HERE")
+	user, err := api.GetUserInfo("U023BECGF")
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	fmt.Printf("ID: %s, Fullname: %s, Email: %s\n", user.ID, user.Profile.RealName, user.Profile.Email)
+}
diff --git a/vendor/github.com/nlopes/slack/examples/websocket/websocket.go b/vendor/github.com/nlopes/slack/examples/websocket/websocket.go
new file mode 100644
index 00000000..612b97c0
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/examples/websocket/websocket.go
@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/nlopes/slack"
+)
+
+func main() {
+	api := slack.New("YOUR TOKEN HERE")
+	logger := log.New(os.Stdout, "slack-bot: ", log.Lshortfile|log.LstdFlags)
+	slack.SetLogger(logger)
+	api.SetDebug(true)
+
+	rtm := api.NewRTM()
+	go rtm.ManageConnection()
+
+Loop:
+	for {
+		select {
+		case msg := <-rtm.IncomingEvents:
+			fmt.Print("Event Received: ")
+			switch ev := msg.Data.(type) {
+			case *slack.HelloEvent:
+				// Ignore hello
+
+			case *slack.ConnectedEvent:
+				fmt.Println("Infos:", ev.Info)
+				fmt.Println("Connection counter:", ev.ConnectionCount)
+				// Replace #general with your Channel ID
+				rtm.SendMessage(rtm.NewOutgoingMessage("Hello world", "#general"))
+
+			case *slack.MessageEvent:
+				fmt.Printf("Message: %v\n", ev)
+
+			case *slack.PresenceChangeEvent:
+				fmt.Printf("Presence Change: %v\n", ev)
+
+			case *slack.LatencyReport:
+				fmt.Printf("Current latency: %v\n", ev.Value)
+
+			case *slack.RTMError:
+				fmt.Printf("Error: %s\n", ev.Error())
+
+			case *slack.InvalidAuthEvent:
+				fmt.Printf("Invalid credentials")
+				break Loop
+
+			default:
+
+				// Ignore other events..
+				// fmt.Printf("Unexpected: %v\n", msg.Data)
+			}
+		}
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/files.go b/vendor/github.com/nlopes/slack/files.go
new file mode 100644
index 00000000..18fc9ba9
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/files.go
@@ -0,0 +1,274 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+const (
+	// Add here the defaults in the siten
+	DEFAULT_FILES_USER    = ""
+	DEFAULT_FILES_CHANNEL = ""
+	DEFAULT_FILES_TS_FROM = 0
+	DEFAULT_FILES_TS_TO   = -1
+	DEFAULT_FILES_TYPES   = "all"
+	DEFAULT_FILES_COUNT   = 100
+	DEFAULT_FILES_PAGE    = 1
+)
+
+// File contains all the information for a file
+type File struct {
+	ID        string   `json:"id"`
+	Created   JSONTime `json:"created"`
+	Timestamp JSONTime `json:"timestamp"`
+
+	Name              string `json:"name"`
+	Title             string `json:"title"`
+	Mimetype          string `json:"mimetype"`
+	ImageExifRotation int    `json:"image_exif_rotation"`
+	Filetype          string `json:"filetype"`
+	PrettyType        string `json:"pretty_type"`
+	User              string `json:"user"`
+
+	Mode         string `json:"mode"`
+	Editable     bool   `json:"editable"`
+	IsExternal   bool   `json:"is_external"`
+	ExternalType string `json:"external_type"`
+
+	Size int `json:"size"`
+
+	URL                string `json:"url"`          // Deprecated - never set
+	URLDownload        string `json:"url_download"` // Deprecated - never set
+	URLPrivate         string `json:"url_private"`
+	URLPrivateDownload string `json:"url_private_download"`
+
+	OriginalH   int    `json:"original_h"`
+	OriginalW   int    `json:"original_w"`
+	Thumb64     string `json:"thumb_64"`
+	Thumb80     string `json:"thumb_80"`
+	Thumb160    string `json:"thumb_160"`
+	Thumb360    string `json:"thumb_360"`
+	Thumb360Gif string `json:"thumb_360_gif"`
+	Thumb360W   int    `json:"thumb_360_w"`
+	Thumb360H   int    `json:"thumb_360_h"`
+	Thumb480    string `json:"thumb_480"`
+	Thumb480W   int    `json:"thumb_480_w"`
+	Thumb480H   int    `json:"thumb_480_h"`
+	Thumb720    string `json:"thumb_720"`
+	Thumb720W   int    `json:"thumb_720_w"`
+	Thumb720H   int    `json:"thumb_720_h"`
+	Thumb960    string `json:"thumb_960"`
+	Thumb960W   int    `json:"thumb_960_w"`
+	Thumb960H   int    `json:"thumb_960_h"`
+	Thumb1024   string `json:"thumb_1024"`
+	Thumb1024W  int    `json:"thumb_1024_w"`
+	Thumb1024H  int    `json:"thumb_1024_h"`
+
+	Permalink       string `json:"permalink"`
+	PermalinkPublic string `json:"permalink_public"`
+
+	EditLink         string `json:"edit_link"`
+	Preview          string `json:"preview"`
+	PreviewHighlight string `json:"preview_highlight"`
+	Lines            int    `json:"lines"`
+	LinesMore        int    `json:"lines_more"`
+
+	IsPublic        bool     `json:"is_public"`
+	PublicURLShared bool     `json:"public_url_shared"`
+	Channels        []string `json:"channels"`
+	Groups          []string `json:"groups"`
+	IMs             []string `json:"ims"`
+	InitialComment  Comment  `json:"initial_comment"`
+	CommentsCount   int      `json:"comments_count"`
+	NumStars        int      `json:"num_stars"`
+	IsStarred       bool     `json:"is_starred"`
+}
+
+// FileUploadParameters contains all the parameters necessary (including the optional ones) for an UploadFile() request
+type FileUploadParameters struct {
+	File           string
+	Content        string
+	Filetype       string
+	Filename       string
+	Title          string
+	InitialComment string
+	Channels       []string
+}
+
+// GetFilesParameters contains all the parameters necessary (including the optional ones) for a GetFiles() request
+type GetFilesParameters struct {
+	User          string
+	Channel       string
+	TimestampFrom JSONTime
+	TimestampTo   JSONTime
+	Types         string
+	Count         int
+	Page          int
+}
+
+type fileResponseFull struct {
+	File     `json:"file"`
+	Paging   `json:"paging"`
+	Comments []Comment `json:"comments"`
+	Files    []File    `json:"files"`
+
+	SlackResponse
+}
+
+// NewGetFilesParameters provides an instance of GetFilesParameters with all the sane default values set
+func NewGetFilesParameters() GetFilesParameters {
+	return GetFilesParameters{
+		User:          DEFAULT_FILES_USER,
+		Channel:       DEFAULT_FILES_CHANNEL,
+		TimestampFrom: DEFAULT_FILES_TS_FROM,
+		TimestampTo:   DEFAULT_FILES_TS_TO,
+		Types:         DEFAULT_FILES_TYPES,
+		Count:         DEFAULT_FILES_COUNT,
+		Page:          DEFAULT_FILES_PAGE,
+	}
+}
+
+func fileRequest(path string, values url.Values, debug bool) (*fileResponseFull, error) {
+	response := &fileResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// GetFileInfo retrieves a file and related comments
+func (api *Client) GetFileInfo(fileID string, count, page int) (*File, []Comment, *Paging, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"file":  {fileID},
+		"count": {strconv.Itoa(count)},
+		"page":  {strconv.Itoa(page)},
+	}
+	response, err := fileRequest("files.info", values, api.debug)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	return &response.File, response.Comments, &response.Paging, nil
+}
+
+// GetFiles retrieves all files according to the parameters given
+func (api *Client) GetFiles(params GetFilesParameters) ([]File, *Paging, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if params.User != DEFAULT_FILES_USER {
+		values.Add("user", params.User)
+	}
+	if params.Channel != DEFAULT_FILES_CHANNEL {
+		values.Add("channel", params.Channel)
+	}
+	// XXX: this is broken. fix it with a proper unix timestamp
+	if params.TimestampFrom != DEFAULT_FILES_TS_FROM {
+		values.Add("ts_from", params.TimestampFrom.String())
+	}
+	if params.TimestampTo != DEFAULT_FILES_TS_TO {
+		values.Add("ts_to", params.TimestampTo.String())
+	}
+	if params.Types != DEFAULT_FILES_TYPES {
+		values.Add("types", params.Types)
+	}
+	if params.Count != DEFAULT_FILES_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Page != DEFAULT_FILES_PAGE {
+		values.Add("page", strconv.Itoa(params.Page))
+	}
+	response, err := fileRequest("files.list", values, api.debug)
+	if err != nil {
+		return nil, nil, err
+	}
+	return response.Files, &response.Paging, nil
+}
+
+// UploadFile uploads a file
+func (api *Client) UploadFile(params FileUploadParameters) (file *File, err error) {
+	// Test if user token is valid. This helps because client.Do doesn't like this for some reason. XXX: More
+	// investigation needed, but for now this will do.
+	_, err = api.AuthTest()
+	if err != nil {
+		return nil, err
+	}
+	response := &fileResponseFull{}
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if params.Filetype != "" {
+		values.Add("filetype", params.Filetype)
+	}
+	if params.Filename != "" {
+		values.Add("filename", params.Filename)
+	}
+	if params.Title != "" {
+		values.Add("title", params.Title)
+	}
+	if params.InitialComment != "" {
+		values.Add("initial_comment", params.InitialComment)
+	}
+	if len(params.Channels) != 0 {
+		values.Add("channels", strings.Join(params.Channels, ","))
+	}
+	if params.Content != "" {
+		values.Add("content", params.Content)
+		err = post("files.upload", values, response, api.debug)
+	} else if params.File != "" {
+		err = postWithMultipartResponse("files.upload", params.File, values, response, api.debug)
+	}
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return &response.File, nil
+}
+
+// DeleteFile deletes a file
+func (api *Client) DeleteFile(fileID string) error {
+	values := url.Values{
+		"token": {api.config.token},
+		"file":  {fileID},
+	}
+	_, err := fileRequest("files.delete", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+
+}
+
+// RevokeFilePublicURL disables public/external sharing for a file
+func (api *Client) RevokeFilePublicURL(fileID string) (*File, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"file":  {fileID},
+	}
+	response, err := fileRequest("files.revokePublicURL", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.File, nil
+}
+
+// ShareFilePublicURL enabled public/external sharing for a file
+func (api *Client) ShareFilePublicURL(fileID string) (*File, []Comment, *Paging, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"file":  {fileID},
+	}
+	response, err := fileRequest("files.sharedPublicURL", values, api.debug)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	return &response.File, response.Comments, &response.Paging, nil
+}
diff --git a/vendor/github.com/nlopes/slack/groups.go b/vendor/github.com/nlopes/slack/groups.go
new file mode 100644
index 00000000..ec4a3b65
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/groups.go
@@ -0,0 +1,293 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+// Group contains all the information for a group
+type Group struct {
+	groupConversation
+	IsGroup bool `json:"is_group"`
+}
+
+type groupResponseFull struct {
+	Group          Group   `json:"group"`
+	Groups         []Group `json:"groups"`
+	Purpose        string  `json:"purpose"`
+	Topic          string  `json:"topic"`
+	NotInGroup     bool    `json:"not_in_group"`
+	NoOp           bool    `json:"no_op"`
+	AlreadyClosed  bool    `json:"already_closed"`
+	AlreadyOpen    bool    `json:"already_open"`
+	AlreadyInGroup bool    `json:"already_in_group"`
+	Channel        Channel `json:"channel"`
+	History
+	SlackResponse
+}
+
+func groupRequest(path string, values url.Values, debug bool) (*groupResponseFull, error) {
+	response := &groupResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// ArchiveGroup archives a private group
+func (api *Client) ArchiveGroup(group string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	_, err := groupRequest("groups.archive", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// UnarchiveGroup unarchives a private group
+func (api *Client) UnarchiveGroup(group string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	_, err := groupRequest("groups.unarchive", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// CreateGroup creates a private group
+func (api *Client) CreateGroup(group string) (*Group, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"name":  {group},
+	}
+	response, err := groupRequest("groups.create", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Group, nil
+}
+
+// CreateChildGroup creates a new private group archiving the old one
+// This method takes an existing private group and performs the following steps:
+//   1. Renames the existing group (from "example" to "example-archived").
+//   2. Archives the existing group.
+//   3. Creates a new group with the name of the existing group.
+//   4. Adds all members of the existing group to the new group.
+func (api *Client) CreateChildGroup(group string) (*Group, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	response, err := groupRequest("groups.createChild", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Group, nil
+}
+
+// CloseGroup closes a private group
+func (api *Client) CloseGroup(group string) (bool, bool, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	response, err := imRequest("groups.close", values, api.debug)
+	if err != nil {
+		return false, false, err
+	}
+	return response.NoOp, response.AlreadyClosed, nil
+}
+
+// GetGroupHistory fetches all the history for a private group
+func (api *Client) GetGroupHistory(group string, params HistoryParameters) (*History, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	if params.Latest != DEFAULT_HISTORY_LATEST {
+		values.Add("latest", params.Latest)
+	}
+	if params.Oldest != DEFAULT_HISTORY_OLDEST {
+		values.Add("oldest", params.Oldest)
+	}
+	if params.Count != DEFAULT_HISTORY_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Inclusive != DEFAULT_HISTORY_INCLUSIVE {
+		if params.Inclusive {
+			values.Add("inclusive", "1")
+		} else {
+			values.Add("inclusive", "0")
+		}
+	}
+	if params.Unreads != DEFAULT_HISTORY_UNREADS {
+		if params.Unreads {
+			values.Add("unreads", "1")
+		} else {
+			values.Add("unreads", "0")
+		}
+	}
+	response, err := groupRequest("groups.history", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.History, nil
+}
+
+// InviteUserToGroup invites a specific user to a private group
+func (api *Client) InviteUserToGroup(group, user string) (*Group, bool, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"user":    {user},
+	}
+	response, err := groupRequest("groups.invite", values, api.debug)
+	if err != nil {
+		return nil, false, err
+	}
+	return &response.Group, response.AlreadyInGroup, nil
+}
+
+// LeaveGroup makes authenticated user leave the group
+func (api *Client) LeaveGroup(group string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	_, err := groupRequest("groups.leave", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// KickUserFromGroup kicks a user from a group
+func (api *Client) KickUserFromGroup(group, user string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"user":    {user},
+	}
+	_, err := groupRequest("groups.kick", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// GetGroups retrieves all groups
+func (api *Client) GetGroups(excludeArchived bool) ([]Group, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if excludeArchived {
+		values.Add("exclude_archived", "1")
+	}
+	response, err := groupRequest("groups.list", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.Groups, nil
+}
+
+// GetGroupInfo retrieves the given group
+func (api *Client) GetGroupInfo(group string) (*Group, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	response, err := groupRequest("groups.info", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Group, nil
+}
+
+// SetGroupReadMark sets the read mark on a private group
+// Clients should try to avoid making this call too often. When needing to mark a read position, a client should set a
+// timer before making the call. In this way, any further updates needed during the timeout will not generate extra
+// calls (just one per channel). This is useful for when reading scroll-back history, or following a busy live
+// channel. A timeout of 5 seconds is a good starting point. Be sure to flush these calls on shutdown/logout.
+func (api *Client) SetGroupReadMark(group, ts string) error {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"ts":      {ts},
+	}
+	_, err := groupRequest("groups.mark", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// OpenGroup opens a private group
+func (api *Client) OpenGroup(group string) (bool, bool, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+	}
+	response, err := groupRequest("groups.open", values, api.debug)
+	if err != nil {
+		return false, false, err
+	}
+	return response.NoOp, response.AlreadyOpen, nil
+}
+
+// RenameGroup renames a group
+// XXX: They return a channel, not a group. What is this crap? :(
+// Inconsistent api it seems.
+func (api *Client) RenameGroup(group, name string) (*Channel, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"name":    {name},
+	}
+	// XXX: the created entry in this call returns a string instead of a number
+	// so I may have to do some workaround to solve it.
+	response, err := groupRequest("groups.rename", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Channel, nil
+
+}
+
+// SetGroupPurpose sets the group purpose
+func (api *Client) SetGroupPurpose(group, purpose string) (string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"purpose": {purpose},
+	}
+	response, err := groupRequest("groups.setPurpose", values, api.debug)
+	if err != nil {
+		return "", err
+	}
+	return response.Purpose, nil
+}
+
+// SetGroupTopic sets the group topic
+func (api *Client) SetGroupTopic(group, topic string) (string, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {group},
+		"topic":   {topic},
+	}
+	response, err := groupRequest("groups.setTopic", values, api.debug)
+	if err != nil {
+		return "", err
+	}
+	return response.Topic, nil
+}
diff --git a/vendor/github.com/nlopes/slack/history.go b/vendor/github.com/nlopes/slack/history.go
new file mode 100644
index 00000000..87b2e1ed
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/history.go
@@ -0,0 +1,36 @@
+package slack
+
+const (
+	DEFAULT_HISTORY_LATEST    = ""
+	DEFAULT_HISTORY_OLDEST    = "0"
+	DEFAULT_HISTORY_COUNT     = 100
+	DEFAULT_HISTORY_INCLUSIVE = false
+	DEFAULT_HISTORY_UNREADS   = false
+)
+
+// HistoryParameters contains all the necessary information to help in the retrieval of history for Channels/Groups/DMs
+type HistoryParameters struct {
+	Latest    string
+	Oldest    string
+	Count     int
+	Inclusive bool
+	Unreads   bool
+}
+
+// History contains message history information needed to navigate a Channel / Group / DM history
+type History struct {
+	Latest   string    `json:"latest"`
+	Messages []Message `json:"messages"`
+	HasMore  bool      `json:"has_more"`
+}
+
+// NewHistoryParameters provides an instance of HistoryParameters with all the sane default values set
+func NewHistoryParameters() HistoryParameters {
+	return HistoryParameters{
+		Latest:    DEFAULT_HISTORY_LATEST,
+		Oldest:    DEFAULT_HISTORY_OLDEST,
+		Count:     DEFAULT_HISTORY_COUNT,
+		Inclusive: DEFAULT_HISTORY_INCLUSIVE,
+		Unreads:   DEFAULT_HISTORY_UNREADS,
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/im.go b/vendor/github.com/nlopes/slack/im.go
new file mode 100644
index 00000000..6fbc39e9
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/im.go
@@ -0,0 +1,130 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+type imChannel struct {
+	ID string `json:"id"`
+}
+
+type imResponseFull struct {
+	NoOp          bool      `json:"no_op"`
+	AlreadyClosed bool      `json:"already_closed"`
+	AlreadyOpen   bool      `json:"already_open"`
+	Channel       imChannel `json:"channel"`
+	IMs           []IM      `json:"ims"`
+	History
+	SlackResponse
+}
+
+// IM contains information related to the Direct Message channel
+type IM struct {
+	conversation
+	IsIM          bool   `json:"is_im"`
+	User          string `json:"user"`
+	IsUserDeleted bool   `json:"is_user_deleted"`
+}
+
+func imRequest(path string, values url.Values, debug bool) (*imResponseFull, error) {
+	response := &imResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// CloseIMChannel closes the direct message channel
+func (api *Client) CloseIMChannel(channel string) (bool, bool, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	response, err := imRequest("im.close", values, api.debug)
+	if err != nil {
+		return false, false, err
+	}
+	return response.NoOp, response.AlreadyClosed, nil
+}
+
+// OpenIMChannel opens a direct message channel to the user provided as argument
+// Returns some status and the channel ID
+func (api *Client) OpenIMChannel(user string) (bool, bool, string, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"user":  {user},
+	}
+	response, err := imRequest("im.open", values, api.debug)
+	if err != nil {
+		return false, false, "", err
+	}
+	return response.NoOp, response.AlreadyOpen, response.Channel.ID, nil
+}
+
+// MarkIMChannel sets the read mark of a direct message channel to a specific point
+func (api *Client) MarkIMChannel(channel, ts string) (err error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+		"ts":      {ts},
+	}
+	_, err = imRequest("im.mark", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return
+}
+
+// GetIMHistory retrieves the direct message channel history
+func (api *Client) GetIMHistory(channel string, params HistoryParameters) (*History, error) {
+	values := url.Values{
+		"token":   {api.config.token},
+		"channel": {channel},
+	}
+	if params.Latest != DEFAULT_HISTORY_LATEST {
+		values.Add("latest", params.Latest)
+	}
+	if params.Oldest != DEFAULT_HISTORY_OLDEST {
+		values.Add("oldest", params.Oldest)
+	}
+	if params.Count != DEFAULT_HISTORY_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Inclusive != DEFAULT_HISTORY_INCLUSIVE {
+		if params.Inclusive {
+			values.Add("inclusive", "1")
+		} else {
+			values.Add("inclusive", "0")
+		}
+	}
+	if params.Unreads != DEFAULT_HISTORY_UNREADS {
+		if params.Unreads {
+			values.Add("unreads", "1")
+		} else {
+			values.Add("unreads", "0")
+		}
+	}
+	response, err := imRequest("im.history", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.History, nil
+}
+
+// GetIMChannels returns the list of direct message channels
+func (api *Client) GetIMChannels() ([]IM, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	response, err := imRequest("im.list", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.IMs, nil
+}
diff --git a/vendor/github.com/nlopes/slack/info.go b/vendor/github.com/nlopes/slack/info.go
new file mode 100644
index 00000000..5f0e5414
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/info.go
@@ -0,0 +1,206 @@
+package slack
+
+import (
+	"fmt"
+	"time"
+)
+
+// UserPrefs needs to be implemented
+type UserPrefs struct {
+	// "highlight_words":"",
+	// "user_colors":"",
+	// "color_names_in_list":true,
+	// "growls_enabled":true,
+	// "tz":"Europe\/London",
+	// "push_dm_alert":true,
+	// "push_mention_alert":true,
+	// "push_everything":true,
+	// "push_idle_wait":2,
+	// "push_sound":"b2.mp3",
+	// "push_loud_channels":"",
+	// "push_mention_channels":"",
+	// "push_loud_channels_set":"",
+	// "email_alerts":"instant",
+	// "email_alerts_sleep_until":0,
+	// "email_misc":false,
+	// "email_weekly":true,
+	// "welcome_message_hidden":false,
+	// "all_channels_loud":true,
+	// "loud_channels":"",
+	// "never_channels":"",
+	// "loud_channels_set":"",
+	// "show_member_presence":true,
+	// "search_sort":"timestamp",
+	// "expand_inline_imgs":true,
+	// "expand_internal_inline_imgs":true,
+	// "expand_snippets":false,
+	// "posts_formatting_guide":true,
+	// "seen_welcome_2":true,
+	// "seen_ssb_prompt":false,
+	// "search_only_my_channels":false,
+	// "emoji_mode":"default",
+	// "has_invited":true,
+	// "has_uploaded":false,
+	// "has_created_channel":true,
+	// "search_exclude_channels":"",
+	// "messages_theme":"default",
+	// "webapp_spellcheck":true,
+	// "no_joined_overlays":false,
+	// "no_created_overlays":true,
+	// "dropbox_enabled":false,
+	// "seen_user_menu_tip_card":true,
+	// "seen_team_menu_tip_card":true,
+	// "seen_channel_menu_tip_card":true,
+	// "seen_message_input_tip_card":true,
+	// "seen_channels_tip_card":true,
+	// "seen_domain_invite_reminder":false,
+	// "seen_member_invite_reminder":false,
+	// "seen_flexpane_tip_card":true,
+	// "seen_search_input_tip_card":true,
+	// "mute_sounds":false,
+	// "arrow_history":false,
+	// "tab_ui_return_selects":true,
+	// "obey_inline_img_limit":true,
+	// "new_msg_snd":"knock_brush.mp3",
+	// "collapsible":false,
+	// "collapsible_by_click":true,
+	// "require_at":false,
+	// "mac_ssb_bounce":"",
+	// "mac_ssb_bullet":true,
+	// "win_ssb_bullet":true,
+	// "expand_non_media_attachments":true,
+	// "show_typing":true,
+	// "pagekeys_handled":true,
+	// "last_snippet_type":"",
+	// "display_real_names_override":0,
+	// "time24":false,
+	// "enter_is_special_in_tbt":false,
+	// "graphic_emoticons":false,
+	// "convert_emoticons":true,
+	// "autoplay_chat_sounds":true,
+	// "ss_emojis":true,
+	// "sidebar_behavior":"",
+	// "mark_msgs_read_immediately":true,
+	// "start_scroll_at_oldest":true,
+	// "snippet_editor_wrap_long_lines":false,
+	// "ls_disabled":false,
+	// "sidebar_theme":"default",
+	// "sidebar_theme_custom_values":"",
+	// "f_key_search":false,
+	// "k_key_omnibox":true,
+	// "speak_growls":false,
+	// "mac_speak_voice":"com.apple.speech.synthesis.voice.Alex",
+	// "mac_speak_speed":250,
+	// "comma_key_prefs":false,
+	// "at_channel_suppressed_channels":"",
+	// "push_at_channel_suppressed_channels":"",
+	// "prompted_for_email_disabling":false,
+	// "full_text_extracts":false,
+	// "no_text_in_notifications":false,
+	// "muted_channels":"",
+	// "no_macssb1_banner":false,
+	// "privacy_policy_seen":true,
+	// "search_exclude_bots":false,
+	// "fuzzy_matching":false
+}
+
+// UserDetails contains user details coming in the initial response from StartRTM
+type UserDetails struct {
+	ID             string    `json:"id"`
+	Name           string    `json:"name"`
+	Created        JSONTime  `json:"created"`
+	ManualPresence string    `json:"manual_presence"`
+	Prefs          UserPrefs `json:"prefs"`
+}
+
+// JSONTime exists so that we can have a String method converting the date
+type JSONTime int64
+
+// String converts the unix timestamp into a string
+func (t JSONTime) String() string {
+	tm := t.Time()
+	return fmt.Sprintf("\"%s\"", tm.Format("Mon Jan _2"))
+}
+
+// Time returns a `time.Time` representation of this value.
+func (t JSONTime) Time() time.Time {
+	return time.Unix(int64(t), 0)
+}
+
+// Team contains details about a team
+type Team struct {
+	ID     string `json:"id"`
+	Name   string `json:"name"`
+	Domain string `json:"domain"`
+}
+
+// Icons XXX: needs further investigation
+type Icons struct {
+	Image48 string `json:"image_48"`
+}
+
+// Bot contains information about a bot
+type Bot struct {
+	ID      string `json:"id"`
+	Name    string `json:"name"`
+	Deleted bool   `json:"deleted"`
+	Icons   Icons  `json:"icons"`
+}
+
+// Info contains various details about Users, Channels, Bots and the authenticated user.
+// It is returned by StartRTM or included in the "ConnectedEvent" RTM event.
+type Info struct {
+	URL      string       `json:"url,omitempty"`
+	User     *UserDetails `json:"self,omitempty"`
+	Team     *Team        `json:"team,omitempty"`
+	Users    []User       `json:"users,omitempty"`
+	Channels []Channel    `json:"channels,omitempty"`
+	Groups   []Group      `json:"groups,omitempty"`
+	Bots     []Bot        `json:"bots,omitempty"`
+	IMs      []IM         `json:"ims,omitempty"`
+}
+
+type infoResponseFull struct {
+	Info
+	WebResponse
+}
+
+// GetBotByID returns a bot given a bot id
+func (info Info) GetBotByID(botID string) *Bot {
+	for _, bot := range info.Bots {
+		if bot.ID == botID {
+			return &bot
+		}
+	}
+	return nil
+}
+
+// GetUserByID returns a user given a user id
+func (info Info) GetUserByID(userID string) *User {
+	for _, user := range info.Users {
+		if user.ID == userID {
+			return &user
+		}
+	}
+	return nil
+}
+
+// GetChannelByID returns a channel given a channel id
+func (info Info) GetChannelByID(channelID string) *Channel {
+	for _, channel := range info.Channels {
+		if channel.ID == channelID {
+			return &channel
+		}
+	}
+	return nil
+}
+
+// GetGroupByID returns a group given a group id
+func (info Info) GetGroupByID(groupID string) *Group {
+	for _, group := range info.Groups {
+		if group.ID == groupID {
+			return &group
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/nlopes/slack/item.go b/vendor/github.com/nlopes/slack/item.go
new file mode 100644
index 00000000..89af4eb1
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/item.go
@@ -0,0 +1,75 @@
+package slack
+
+const (
+	TYPE_MESSAGE      = "message"
+	TYPE_FILE         = "file"
+	TYPE_FILE_COMMENT = "file_comment"
+	TYPE_CHANNEL      = "channel"
+	TYPE_IM           = "im"
+	TYPE_GROUP        = "group"
+)
+
+// Item is any type of slack message - message, file, or file comment.
+type Item struct {
+	Type      string   `json:"type"`
+	Channel   string   `json:"channel,omitempty"`
+	Message   *Message `json:"message,omitempty"`
+	File      *File    `json:"file,omitempty"`
+	Comment   *Comment `json:"comment,omitempty"`
+	Timestamp string   `json:"ts,omitempty"`
+}
+
+// NewMessageItem turns a message on a channel into a typed message struct.
+func NewMessageItem(ch string, m *Message) Item {
+	return Item{Type: TYPE_MESSAGE, Channel: ch, Message: m}
+}
+
+// NewFileItem turns a file into a typed file struct.
+func NewFileItem(f *File) Item {
+	return Item{Type: TYPE_FILE, File: f}
+}
+
+// NewFileCommentItem turns a file and comment into a typed file_comment struct.
+func NewFileCommentItem(f *File, c *Comment) Item {
+	return Item{Type: TYPE_FILE_COMMENT, File: f, Comment: c}
+}
+
+// NewChannelItem turns a channel id into a typed channel struct.
+func NewChannelItem(ch string) Item {
+	return Item{Type: TYPE_CHANNEL, Channel: ch}
+}
+
+// NewIMItem turns a channel id into a typed im struct.
+func NewIMItem(ch string) Item {
+	return Item{Type: TYPE_IM, Channel: ch}
+}
+
+// NewGroupItem turns a channel id into a typed group struct.
+func NewGroupItem(ch string) Item {
+	return Item{Type: TYPE_GROUP, Channel: ch}
+}
+
+// ItemRef is a reference to a message of any type. One of FileID,
+// CommentId, or the combination of ChannelId and Timestamp must be
+// specified.
+type ItemRef struct {
+	Channel   string `json:"channel"`
+	Timestamp string `json:"timestamp"`
+	File      string `json:"file"`
+	Comment   string `json:"file_comment"`
+}
+
+// NewRefToMessage initializes a reference to to a message.
+func NewRefToMessage(channel, timestamp string) ItemRef {
+	return ItemRef{Channel: channel, Timestamp: timestamp}
+}
+
+// NewRefToFile initializes a reference to a file.
+func NewRefToFile(file string) ItemRef {
+	return ItemRef{File: file}
+}
+
+// NewRefToComment initializes a reference to a file comment.
+func NewRefToComment(comment string) ItemRef {
+	return ItemRef{Comment: comment}
+}
diff --git a/vendor/github.com/nlopes/slack/messageID.go b/vendor/github.com/nlopes/slack/messageID.go
new file mode 100644
index 00000000..a17472b4
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/messageID.go
@@ -0,0 +1,30 @@
+package slack
+
+import "sync"
+
+// IDGenerator provides an interface for generating integer ID values.
+type IDGenerator interface {
+	Next() int
+}
+
+// NewSafeID returns a new instance of an IDGenerator which is safe for
+// concurrent use by multiple goroutines.
+func NewSafeID(startID int) IDGenerator {
+	return &safeID{
+		nextID: startID,
+		mutex:  &sync.Mutex{},
+	}
+}
+
+type safeID struct {
+	nextID int
+	mutex  *sync.Mutex
+}
+
+func (s *safeID) Next() int {
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+	id := s.nextID
+	s.nextID++
+	return id
+}
diff --git a/vendor/github.com/nlopes/slack/messages.go b/vendor/github.com/nlopes/slack/messages.go
new file mode 100644
index 00000000..3433e06b
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/messages.go
@@ -0,0 +1,131 @@
+package slack
+
+// OutgoingMessage is used for the realtime API, and seems incomplete.
+type OutgoingMessage struct {
+	ID      int    `json:"id"`
+	Channel string `json:"channel,omitempty"`
+	Text    string `json:"text,omitempty"`
+	Type    string `json:"type,omitempty"`
+}
+
+// Message is an auxiliary type to allow us to have a message containing sub messages
+type Message struct {
+	Msg
+	SubMessage *Msg `json:"message,omitempty"`
+}
+
+// Msg contains information about a slack message
+type Msg struct {
+	// Basic Message
+	Type        string       `json:"type,omitempty"`
+	Channel     string       `json:"channel,omitempty"`
+	User        string       `json:"user,omitempty"`
+	Text        string       `json:"text,omitempty"`
+	Timestamp   string       `json:"ts,omitempty"`
+	IsStarred   bool         `json:"is_starred,omitempty"`
+	PinnedTo    []string     `json:"pinned_to, omitempty"`
+	Attachments []Attachment `json:"attachments,omitempty"`
+	Edited      *Edited      `json:"edited,omitempty"`
+
+	// Message Subtypes
+	SubType string `json:"subtype,omitempty"`
+
+	// Hidden Subtypes
+	Hidden           bool   `json:"hidden,omitempty"`     // message_changed, message_deleted, unpinned_item
+	DeletedTimestamp string `json:"deleted_ts,omitempty"` // message_deleted
+	EventTimestamp   string `json:"event_ts,omitempty"`
+
+	// bot_message (https://api.slack.com/events/message/bot_message)
+	BotID    string `json:"bot_id,omitempty"`
+	Username string `json:"username,omitempty"`
+	Icons    *Icon  `json:"icons,omitempty"`
+
+	// channel_join, group_join
+	Inviter string `json:"inviter,omitempty"`
+
+	// channel_topic, group_topic
+	Topic string `json:"topic,omitempty"`
+
+	// channel_purpose, group_purpose
+	Purpose string `json:"purpose,omitempty"`
+
+	// channel_name, group_name
+	Name    string `json:"name,omitempty"`
+	OldName string `json:"old_name,omitempty"`
+
+	// channel_archive, group_archive
+	Members []string `json:"members,omitempty"`
+
+	// file_share, file_comment, file_mention
+	File *File `json:"file,omitempty"`
+
+	// file_share
+	Upload bool `json:"upload,omitempty"`
+
+	// file_comment
+	Comment *Comment `json:"comment,omitempty"`
+
+	// pinned_item
+	ItemType string `json:"item_type,omitempty"`
+
+	// https://api.slack.com/rtm
+	ReplyTo int    `json:"reply_to,omitempty"`
+	Team    string `json:"team,omitempty"`
+
+	// reactions
+	Reactions []ItemReaction `json:"reactions,omitempty"`
+}
+
+// Icon is used for bot messages
+type Icon struct {
+	IconURL   string `json:"icon_url,omitempty"`
+	IconEmoji string `json:"icon_emoji,omitempty"`
+}
+
+// Edited indicates that a message has been edited.
+type Edited struct {
+	User      string `json:"user,omitempty"`
+	Timestamp string `json:"ts,omitempty"`
+}
+
+// Event contains the event type
+type Event struct {
+	Type string `json:"type,omitempty"`
+}
+
+// Ping contains information about a Ping Event
+type Ping struct {
+	ID   int    `json:"id"`
+	Type string `json:"type"`
+}
+
+// Pong contains information about a Pong Event
+type Pong struct {
+	Type    string `json:"type"`
+	ReplyTo int    `json:"reply_to"`
+}
+
+// NewOutgoingMessage prepares an OutgoingMessage that the user can
+// use to send a message. Use this function to properly set the
+// messageID.
+func (rtm *RTM) NewOutgoingMessage(text string, channel string) *OutgoingMessage {
+	id := rtm.idGen.Next()
+	return &OutgoingMessage{
+		ID:      id,
+		Type:    "message",
+		Channel: channel,
+		Text:    text,
+	}
+}
+
+// NewTypingMessage prepares an OutgoingMessage that the user can
+// use to send as a typing indicator. Use this function to properly set the
+// messageID.
+func (rtm *RTM) NewTypingMessage(channel string) *OutgoingMessage {
+	id := rtm.idGen.Next()
+	return &OutgoingMessage{
+		ID:      id,
+		Type:    "typing",
+		Channel: channel,
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/misc.go b/vendor/github.com/nlopes/slack/misc.go
new file mode 100644
index 00000000..c0f023cb
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/misc.go
@@ -0,0 +1,119 @@
+package slack
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime/multipart"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+var HTTPClient = &http.Client{}
+
+type WebResponse struct {
+	Ok    bool      `json:"ok"`
+	Error *WebError `json:"error"`
+}
+
+type WebError string
+
+func (s WebError) Error() string {
+	return string(s)
+}
+
+func fileUploadReq(path, fpath string, values url.Values) (*http.Request, error) {
+	fullpath, err := filepath.Abs(fpath)
+	if err != nil {
+		return nil, err
+	}
+	file, err := os.Open(fullpath)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	body := &bytes.Buffer{}
+	wr := multipart.NewWriter(body)
+
+	ioWriter, err := wr.CreateFormFile("file", filepath.Base(fullpath))
+	if err != nil {
+		wr.Close()
+		return nil, err
+	}
+	bytes, err := io.Copy(ioWriter, file)
+	if err != nil {
+		wr.Close()
+		return nil, err
+	}
+	// Close the multipart writer or the footer won't be written
+	wr.Close()
+	stat, err := file.Stat()
+	if err != nil {
+		return nil, err
+	}
+	if bytes != stat.Size() {
+		return nil, errors.New("could not read the whole file")
+	}
+	req, err := http.NewRequest("POST", path, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Add("Content-Type", wr.FormDataContentType())
+	req.URL.RawQuery = (values).Encode()
+	return req, nil
+}
+
+func parseResponseBody(body io.ReadCloser, intf *interface{}, debug bool) error {
+	response, err := ioutil.ReadAll(body)
+	if err != nil {
+		return err
+	}
+
+	// FIXME: will be api.Debugf
+	if debug {
+		logger.Printf("parseResponseBody: %s\n", string(response))
+	}
+
+	err = json.Unmarshal(response, &intf)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func postWithMultipartResponse(path string, filepath string, values url.Values, intf interface{}, debug bool) error {
+	req, err := fileUploadReq(SLACK_API+path, filepath, values)
+	resp, err := HTTPClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	return parseResponseBody(resp.Body, &intf, debug)
+}
+
+func postForm(endpoint string, values url.Values, intf interface{}, debug bool) error {
+	resp, err := HTTPClient.PostForm(endpoint, values)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	return parseResponseBody(resp.Body, &intf, debug)
+}
+
+func post(path string, values url.Values, intf interface{}, debug bool) error {
+	return postForm(SLACK_API+path, values, intf, debug)
+}
+
+func parseAdminResponse(method string, teamName string, values url.Values, intf interface{}, debug bool) error {
+	endpoint := fmt.Sprintf(SLACK_WEB_API_FORMAT, teamName, method, time.Now().Unix())
+	return postForm(endpoint, values, intf, debug)
+}
diff --git a/vendor/github.com/nlopes/slack/oauth.go b/vendor/github.com/nlopes/slack/oauth.go
new file mode 100644
index 00000000..33c3ed2d
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/oauth.go
@@ -0,0 +1,54 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+)
+
+type OAuthResponseIncomingWebhook struct {
+	URL              string `json:"url"`
+	Channel          string `json:"channel"`
+	ConfigurationURL string `json:"configuration_url"`
+}
+
+type OAuthResponseBot struct {
+	BotUserID      string `json:"bot_user_id"`
+	BotAccessToken string `json:"bot_access_token"`
+}
+
+type OAuthResponse struct {
+	AccessToken     string                       `json:"access_token"`
+	Scope           string                       `json:"scope"`
+	TeamName        string                       `json:"team_name"`
+	TeamID          string                       `json:"team_id"`
+	IncomingWebhook OAuthResponseIncomingWebhook `json:"incoming_webhook"`
+	Bot             OAuthResponseBot             `json:"bot"`
+	SlackResponse
+}
+
+// GetOAuthToken retrieves an AccessToken
+func GetOAuthToken(clientID, clientSecret, code, redirectURI string, debug bool) (accessToken string, scope string, err error) {
+	response, err := GetOAuthResponse(clientID, clientSecret, code, redirectURI, debug)
+	if err != nil {
+		return "", "", err
+	}
+	return response.AccessToken, response.Scope, nil
+}
+
+func GetOAuthResponse(clientID, clientSecret, code, redirectURI string, debug bool) (resp *OAuthResponse, err error) {
+	values := url.Values{
+		"client_id":     {clientID},
+		"client_secret": {clientSecret},
+		"code":          {code},
+		"redirect_uri":  {redirectURI},
+	}
+	response := &OAuthResponse{}
+	err = post("oauth.access", values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
diff --git a/vendor/github.com/nlopes/slack/pagination.go b/vendor/github.com/nlopes/slack/pagination.go
new file mode 100644
index 00000000..87dd136a
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/pagination.go
@@ -0,0 +1,20 @@
+package slack
+
+// Paging contains paging information
+type Paging struct {
+	Count int `json:"count"`
+	Total int `json:"total"`
+	Page  int `json:"page"`
+	Pages int `json:"pages"`
+}
+
+// Pagination contains pagination information
+// This is different from Paging in that it contains additional details
+type Pagination struct {
+	TotalCount int `json:"total_count"`
+	Page       int `json:"page"`
+	PerPage    int `json:"per_page"`
+	PageCount  int `json:"page_count"`
+	First      int `json:"first"`
+	Last       int `json:"last"`
+}
diff --git a/vendor/github.com/nlopes/slack/pins.go b/vendor/github.com/nlopes/slack/pins.go
new file mode 100644
index 00000000..b95efbb6
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/pins.go
@@ -0,0 +1,79 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+)
+
+type listPinsResponseFull struct {
+	Items  []Item
+	Paging `json:"paging"`
+	SlackResponse
+}
+
+// AddPin pins an item in a channel
+func (api *Client) AddPin(channel string, item ItemRef) error {
+	values := url.Values{
+		"channel": {channel},
+		"token":   {api.config.token},
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("pins.add", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// RemovePin un-pins an item from a channel
+func (api *Client) RemovePin(channel string, item ItemRef) error {
+	values := url.Values{
+		"channel": {channel},
+		"token":   {api.config.token},
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("pins.remove", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// ListPins returns information about the items a user reacted to.
+func (api *Client) ListPins(channel string) ([]Item, *Paging, error) {
+	values := url.Values{
+		"channel": {channel},
+		"token":   {api.config.token},
+	}
+	response := &listPinsResponseFull{}
+	err := post("pins.list", values, response, api.debug)
+	if err != nil {
+		return nil, nil, err
+	}
+	if !response.Ok {
+		return nil, nil, errors.New(response.Error)
+	}
+	return response.Items, &response.Paging, nil
+}
diff --git a/vendor/github.com/nlopes/slack/reactions.go b/vendor/github.com/nlopes/slack/reactions.go
new file mode 100644
index 00000000..8769543d
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/reactions.go
@@ -0,0 +1,246 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+// ItemReaction is the reactions that have happened on an item.
+type ItemReaction struct {
+	Name  string   `json:"name"`
+	Count int      `json:"count"`
+	Users []string `json:"users"`
+}
+
+// ReactedItem is an item that was reacted to, and the details of the
+// reactions.
+type ReactedItem struct {
+	Item
+	Reactions []ItemReaction
+}
+
+// GetReactionsParameters is the inputs to get reactions to an item.
+type GetReactionsParameters struct {
+	Full bool
+}
+
+// NewGetReactionsParameters initializes the inputs to get reactions to an item.
+func NewGetReactionsParameters() GetReactionsParameters {
+	return GetReactionsParameters{
+		Full: false,
+	}
+}
+
+type getReactionsResponseFull struct {
+	Type string
+	M    struct {
+		Reactions []ItemReaction
+	} `json:"message"`
+	F struct {
+		Reactions []ItemReaction
+	} `json:"file"`
+	FC struct {
+		Reactions []ItemReaction
+	} `json:"comment"`
+	SlackResponse
+}
+
+func (res getReactionsResponseFull) extractReactions() []ItemReaction {
+	switch res.Type {
+	case "message":
+		return res.M.Reactions
+	case "file":
+		return res.F.Reactions
+	case "file_comment":
+		return res.FC.Reactions
+	}
+	return []ItemReaction{}
+}
+
+const (
+	DEFAULT_REACTIONS_USER  = ""
+	DEFAULT_REACTIONS_COUNT = 100
+	DEFAULT_REACTIONS_PAGE  = 1
+	DEFAULT_REACTIONS_FULL  = false
+)
+
+// ListReactionsParameters is the inputs to find all reactions by a user.
+type ListReactionsParameters struct {
+	User  string
+	Count int
+	Page  int
+	Full  bool
+}
+
+// NewListReactionsParameters initializes the inputs to find all reactions
+// performed by a user.
+func NewListReactionsParameters() ListReactionsParameters {
+	return ListReactionsParameters{
+		User:  DEFAULT_REACTIONS_USER,
+		Count: DEFAULT_REACTIONS_COUNT,
+		Page:  DEFAULT_REACTIONS_PAGE,
+		Full:  DEFAULT_REACTIONS_FULL,
+	}
+}
+
+type listReactionsResponseFull struct {
+	Items []struct {
+		Type    string
+		Channel string
+		M       struct {
+			*Message
+		} `json:"message"`
+		F struct {
+			*File
+			Reactions []ItemReaction
+		} `json:"file"`
+		FC struct {
+			*Comment
+			Reactions []ItemReaction
+		} `json:"comment"`
+	}
+	Paging `json:"paging"`
+	SlackResponse
+}
+
+func (res listReactionsResponseFull) extractReactedItems() []ReactedItem {
+	items := make([]ReactedItem, len(res.Items))
+	for i, input := range res.Items {
+		item := ReactedItem{}
+		item.Type = input.Type
+		switch input.Type {
+		case "message":
+			item.Channel = input.Channel
+			item.Message = input.M.Message
+			item.Reactions = input.M.Reactions
+		case "file":
+			item.File = input.F.File
+			item.Reactions = input.F.Reactions
+		case "file_comment":
+			item.File = input.F.File
+			item.Comment = input.FC.Comment
+			item.Reactions = input.FC.Reactions
+		}
+		items[i] = item
+	}
+	return items
+}
+
+// AddReaction adds a reaction emoji to a message, file or file comment.
+func (api *Client) AddReaction(name string, item ItemRef) error {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if name != "" {
+		values.Set("name", name)
+	}
+	if item.Channel != "" {
+		values.Set("channel", string(item.Channel))
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("reactions.add", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// RemoveReaction removes a reaction emoji from a message, file or file comment.
+func (api *Client) RemoveReaction(name string, item ItemRef) error {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if name != "" {
+		values.Set("name", name)
+	}
+	if item.Channel != "" {
+		values.Set("channel", string(item.Channel))
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("reactions.remove", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// GetReactions returns details about the reactions on an item.
+func (api *Client) GetReactions(item ItemRef, params GetReactionsParameters) ([]ItemReaction, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if item.Channel != "" {
+		values.Set("channel", string(item.Channel))
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	if params.Full != DEFAULT_REACTIONS_FULL {
+		values.Set("full", strconv.FormatBool(params.Full))
+	}
+	response := &getReactionsResponseFull{}
+	if err := post("reactions.get", values, response, api.debug); err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response.extractReactions(), nil
+}
+
+// ListReactions returns information about the items a user reacted to.
+func (api *Client) ListReactions(params ListReactionsParameters) ([]ReactedItem, *Paging, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if params.User != DEFAULT_REACTIONS_USER {
+		values.Add("user", params.User)
+	}
+	if params.Count != DEFAULT_REACTIONS_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Page != DEFAULT_REACTIONS_PAGE {
+		values.Add("page", strconv.Itoa(params.Page))
+	}
+	if params.Full != DEFAULT_REACTIONS_FULL {
+		values.Add("full", strconv.FormatBool(params.Full))
+	}
+	response := &listReactionsResponseFull{}
+	err := post("reactions.list", values, response, api.debug)
+	if err != nil {
+		return nil, nil, err
+	}
+	if !response.Ok {
+		return nil, nil, errors.New(response.Error)
+	}
+	return response.extractReactedItems(), &response.Paging, nil
+}
diff --git a/vendor/github.com/nlopes/slack/rtm.go b/vendor/github.com/nlopes/slack/rtm.go
new file mode 100644
index 00000000..f3552c53
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/rtm.go
@@ -0,0 +1,39 @@
+package slack
+
+import (
+	"fmt"
+	"net/url"
+)
+
+// StartRTM calls the "rtm.start" endpoint and returns the provided URL and the full Info
+// block.
+//
+// To have a fully managed Websocket connection, use `NewRTM`, and call `ManageConnection()`
+// on it.
+func (api *Client) StartRTM() (info *Info, websocketURL string, err error) {
+	response := &infoResponseFull{}
+	err = post("rtm.start", url.Values{"token": {api.config.token}}, response, api.debug)
+	if err != nil {
+		return nil, "", fmt.Errorf("post: %s", err)
+	}
+	if !response.Ok {
+		return nil, "", response.Error
+	}
+
+	// websocket.Dial does not accept url without the port (yet)
+	// Fixed by: https://github.com/golang/net/commit/5058c78c3627b31e484a81463acd51c7cecc06f3
+	// but slack returns the address with no port, so we have to fix it
+	api.Debugln("Using URL:", response.Info.URL)
+	websocketURL, err = websocketizeURLPort(response.Info.URL)
+	if err != nil {
+		return nil, "", fmt.Errorf("parsing response URL: %s", err)
+	}
+
+	return &response.Info, websocketURL, nil
+}
+
+// NewRTM returns a RTM, which provides a fully managed connection to
+// Slack's websocket-based Real-Time Messaging protocol./
+func (api *Client) NewRTM() *RTM {
+	return newRTM(api)
+}
diff --git a/vendor/github.com/nlopes/slack/search.go b/vendor/github.com/nlopes/slack/search.go
new file mode 100644
index 00000000..ab3c5dad
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/search.go
@@ -0,0 +1,137 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+const (
+	DEFAULT_SEARCH_SORT      = "score"
+	DEFAULT_SEARCH_SORT_DIR  = "desc"
+	DEFAULT_SEARCH_HIGHLIGHT = false
+	DEFAULT_SEARCH_COUNT     = 100
+	DEFAULT_SEARCH_PAGE      = 1
+)
+
+type SearchParameters struct {
+	Sort          string
+	SortDirection string
+	Highlight     bool
+	Count         int
+	Page          int
+}
+
+type CtxChannel struct {
+	ID   string `json:"id"`
+	Name string `json:"name"`
+}
+
+type CtxMessage struct {
+	User      string `json:"user"`
+	Username  string `json:"username"`
+	Text      string `json:"text"`
+	Timestamp string `json:"ts"`
+	Type      string `json:"type"`
+}
+
+type SearchMessage struct {
+	Type      string     `json:"type"`
+	Channel   CtxChannel `json:"channel"`
+	User      string     `json:"user"`
+	Username  string     `json:"username"`
+	Timestamp string     `json:"ts"`
+	Text      string     `json:"text"`
+	Permalink string     `json:"permalink"`
+	Previous  CtxMessage `json:"previous"`
+	Previous2 CtxMessage `json:"previous_2"`
+	Next      CtxMessage `json:"next"`
+	Next2     CtxMessage `json:"next_2"`
+}
+
+type SearchMessages struct {
+	Matches    []SearchMessage `json:"matches"`
+	Paging     `json:"paging"`
+	Pagination `json:"pagination"`
+	Total      int `json:"total"`
+}
+
+type SearchFiles struct {
+	Matches    []File `json:"matches"`
+	Paging     `json:"paging"`
+	Pagination `json:"pagination"`
+	Total      int `json:"total"`
+}
+
+type searchResponseFull struct {
+	Query          string `json:"query"`
+	SearchMessages `json:"messages"`
+	SearchFiles    `json:"files"`
+	SlackResponse
+}
+
+func NewSearchParameters() SearchParameters {
+	return SearchParameters{
+		Sort:          DEFAULT_SEARCH_SORT,
+		SortDirection: DEFAULT_SEARCH_SORT_DIR,
+		Highlight:     DEFAULT_SEARCH_HIGHLIGHT,
+		Count:         DEFAULT_SEARCH_COUNT,
+		Page:          DEFAULT_SEARCH_PAGE,
+	}
+}
+
+func (api *Client) _search(path, query string, params SearchParameters, files, messages bool) (response *searchResponseFull, error error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"query": {query},
+	}
+	if params.Sort != DEFAULT_SEARCH_SORT {
+		values.Add("sort", params.Sort)
+	}
+	if params.SortDirection != DEFAULT_SEARCH_SORT_DIR {
+		values.Add("sort_dir", params.SortDirection)
+	}
+	if params.Highlight != DEFAULT_SEARCH_HIGHLIGHT {
+		values.Add("highlight", strconv.Itoa(1))
+	}
+	if params.Count != DEFAULT_SEARCH_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Page != DEFAULT_SEARCH_PAGE {
+		values.Add("page", strconv.Itoa(params.Page))
+	}
+	response = &searchResponseFull{}
+	err := post(path, values, response, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+
+}
+
+func (api *Client) Search(query string, params SearchParameters) (*SearchMessages, *SearchFiles, error) {
+	response, err := api._search("search.all", query, params, true, true)
+	if err != nil {
+		return nil, nil, err
+	}
+	return &response.SearchMessages, &response.SearchFiles, nil
+}
+
+func (api *Client) SearchFiles(query string, params SearchParameters) (*SearchFiles, error) {
+	response, err := api._search("search.files", query, params, true, false)
+	if err != nil {
+		return nil, err
+	}
+	return &response.SearchFiles, nil
+}
+
+func (api *Client) SearchMessages(query string, params SearchParameters) (*SearchMessages, error) {
+	response, err := api._search("search.messages", query, params, false, true)
+	if err != nil {
+		return nil, err
+	}
+	return &response.SearchMessages, nil
+}
diff --git a/vendor/github.com/nlopes/slack/slack.go b/vendor/github.com/nlopes/slack/slack.go
new file mode 100644
index 00000000..eb686354
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/slack.go
@@ -0,0 +1,88 @@
+package slack
+
+import (
+	"errors"
+	"log"
+	"net/url"
+	"os"
+)
+
+var logger *log.Logger // A logger that can be set by consumers
+/*
+  Added as a var so that we can change this for testing purposes
+*/
+var SLACK_API string = "https://slack.com/api/"
+var SLACK_WEB_API_FORMAT string = "https://%s.slack.com/api/users.admin.%s?t=%s"
+
+type SlackResponse struct {
+	Ok    bool   `json:"ok"`
+	Error string `json:"error"`
+}
+
+type AuthTestResponse struct {
+	URL    string `json:"url"`
+	Team   string `json:"team"`
+	User   string `json:"user"`
+	TeamID string `json:"team_id"`
+	UserID string `json:"user_id"`
+}
+
+type authTestResponseFull struct {
+	SlackResponse
+	AuthTestResponse
+}
+
+type Client struct {
+	config struct {
+		token string
+	}
+	info  Info
+	debug bool
+}
+
+// SetLogger let's library users supply a logger, so that api debugging
+// can be logged along with the application's debugging info.
+func SetLogger(l *log.Logger) {
+	logger = l
+}
+
+func New(token string) *Client {
+	s := &Client{}
+	s.config.token = token
+	return s
+}
+
+// AuthTest tests if the user is able to do authenticated requests or not
+func (api *Client) AuthTest() (response *AuthTestResponse, error error) {
+	responseFull := &authTestResponseFull{}
+	err := post("auth.test", url.Values{"token": {api.config.token}}, responseFull, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	if !responseFull.Ok {
+		return nil, errors.New(responseFull.Error)
+	}
+	return &responseFull.AuthTestResponse, nil
+}
+
+// SetDebug switches the api into debug mode
+// When in debug mode, it logs various info about what its doing
+// If you ever use this in production, don't call SetDebug(true)
+func (api *Client) SetDebug(debug bool) {
+	api.debug = debug
+	if debug && logger == nil {
+		logger = log.New(os.Stdout, "nlopes/slack", log.LstdFlags | log.Lshortfile)
+	}
+}
+
+func (api *Client) Debugf(format string, v ...interface{}) {
+	if api.debug {
+		logger.Printf(format, v...)
+	}
+}
+
+func (api *Client) Debugln(v ...interface{}) {
+	if api.debug {
+		logger.Println(v...)
+	}
+}
diff --git a/vendor/github.com/nlopes/slack/stars.go b/vendor/github.com/nlopes/slack/stars.go
new file mode 100644
index 00000000..cc12e6ec
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/stars.go
@@ -0,0 +1,135 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+	"strconv"
+)
+
+const (
+	DEFAULT_STARS_USER  = ""
+	DEFAULT_STARS_COUNT = 100
+	DEFAULT_STARS_PAGE  = 1
+)
+
+type StarsParameters struct {
+	User  string
+	Count int
+	Page  int
+}
+
+type StarredItem Item
+
+type listResponseFull struct {
+	Items  []Item `json:"items"`
+	Paging `json:"paging"`
+	SlackResponse
+}
+
+// NewStarsParameters initialises StarsParameters with default values
+func NewStarsParameters() StarsParameters {
+	return StarsParameters{
+		User:  DEFAULT_STARS_USER,
+		Count: DEFAULT_STARS_COUNT,
+		Page:  DEFAULT_STARS_PAGE,
+	}
+}
+
+// AddStar stars an item in a channel
+func (api *Client) AddStar(channel string, item ItemRef) error {
+	values := url.Values{
+		"channel": {channel},
+		"token":   {api.config.token},
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("stars.add", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// RemoveStar removes a starred item from a channel
+func (api *Client) RemoveStar(channel string, item ItemRef) error {
+	values := url.Values{
+		"channel": {channel},
+		"token":   {api.config.token},
+	}
+	if item.Timestamp != "" {
+		values.Set("timestamp", string(item.Timestamp))
+	}
+	if item.File != "" {
+		values.Set("file", string(item.File))
+	}
+	if item.Comment != "" {
+		values.Set("file_comment", string(item.Comment))
+	}
+	response := &SlackResponse{}
+	if err := post("stars.remove", values, response, api.debug); err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// ListStars returns information about the stars a user added
+func (api *Client) ListStars(params StarsParameters) ([]Item, *Paging, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if params.User != DEFAULT_STARS_USER {
+		values.Add("user", params.User)
+	}
+	if params.Count != DEFAULT_STARS_COUNT {
+		values.Add("count", strconv.Itoa(params.Count))
+	}
+	if params.Page != DEFAULT_STARS_PAGE {
+		values.Add("page", strconv.Itoa(params.Page))
+	}
+	response := &listResponseFull{}
+	err := post("stars.list", values, response, api.debug)
+	if err != nil {
+		return nil, nil, err
+	}
+	if !response.Ok {
+		return nil, nil, errors.New(response.Error)
+	}
+	return response.Items, &response.Paging, nil
+}
+
+// GetStarred returns a list of StarredItem items. The user then has to iterate over them and figure out what they should
+// be looking at according to what is in the Type.
+//    for _, item := range items {
+//        switch c.Type {
+//        case "file_comment":
+//            log.Println(c.Comment)
+//        case "file":
+//             ...
+//
+//    }
+// This function still exists to maintain backwards compatibility.
+// I exposed it as returning []StarredItem, so it shall stay as StarredItem
+func (api *Client) GetStarred(params StarsParameters) ([]StarredItem, *Paging, error) {
+	items, paging, err := api.ListStars(params)
+	if err != nil {
+		return nil, nil, err
+	}
+	starredItems := make([]StarredItem, len(items))
+	for i, item := range items {
+		starredItems[i] = StarredItem(item)
+	}
+	return starredItems, paging, nil
+}
diff --git a/vendor/github.com/nlopes/slack/team.go b/vendor/github.com/nlopes/slack/team.go
new file mode 100644
index 00000000..41507f68
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/team.go
@@ -0,0 +1,46 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+)
+
+type TeamResponse struct {
+	Team TeamInfo `json:"team"`
+	SlackResponse
+}
+
+type TeamInfo struct {
+	ID          string                 `json:"id"`
+	Name        string                 `json:"name"`
+	Domain      string                 `json:"domain"`
+	EmailDomain string                 `json:"email_domain"`
+	Icon        map[string]interface{} `json:"icon"`
+}
+
+func teamRequest(path string, values url.Values, debug bool) (*TeamResponse, error) {
+	response := &TeamResponse{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+
+	return response, nil
+}
+
+// GetTeamInfo gets the Team Information of the user
+func (api *Client) GetTeamInfo() (*TeamInfo, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+
+	response, err := teamRequest("team.info", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.Team, nil
+}
diff --git a/vendor/github.com/nlopes/slack/users.go b/vendor/github.com/nlopes/slack/users.go
new file mode 100644
index 00000000..a0ed81e6
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/users.go
@@ -0,0 +1,140 @@
+package slack
+
+import (
+	"errors"
+	"net/url"
+)
+
+// UserProfile contains all the information details of a given user
+type UserProfile struct {
+	FirstName          string `json:"first_name"`
+	LastName           string `json:"last_name"`
+	RealName           string `json:"real_name"`
+	RealNameNormalized string `json:"real_name_normalized"`
+	Email              string `json:"email"`
+	Skype              string `json:"skype"`
+	Phone              string `json:"phone"`
+	Image24            string `json:"image_24"`
+	Image32            string `json:"image_32"`
+	Image48            string `json:"image_48"`
+	Image72            string `json:"image_72"`
+	Image192           string `json:"image_192"`
+	ImageOriginal      string `json:"image_original"`
+	Title              string `json:"title"`
+}
+
+// User contains all the information of a user
+type User struct {
+	ID                string      `json:"id"`
+	Name              string      `json:"name"`
+	Deleted           bool        `json:"deleted"`
+	Color             string      `json:"color"`
+	RealName          string      `json:"real_name"`
+	TZ                string      `json:"tz,omitempty"`
+	TZLabel           string      `json:"tz_label"`
+	TZOffset          int         `json:"tz_offset"`
+	Profile           UserProfile `json:"profile"`
+	IsBot             bool        `json:"is_bot"`
+	IsAdmin           bool        `json:"is_admin"`
+	IsOwner           bool        `json:"is_owner"`
+	IsPrimaryOwner    bool        `json:"is_primary_owner"`
+	IsRestricted      bool        `json:"is_restricted"`
+	IsUltraRestricted bool        `json:"is_ultra_restricted"`
+	Has2FA            bool        `json:"has_2fa"`
+	HasFiles          bool        `json:"has_files"`
+	Presence          string      `json:"presence"`
+}
+
+// UserPresence contains details about a user online status
+type UserPresence struct {
+	Presence        string   `json:"presence,omitempty"`
+	Online          bool     `json:"online,omitempty"`
+	AutoAway        bool     `json:"auto_away,omitempty"`
+	ManualAway      bool     `json:"manual_away,omitempty"`
+	ConnectionCount int      `json:"connection_count,omitempty"`
+	LastActivity    JSONTime `json:"last_activity,omitempty"`
+}
+
+type userResponseFull struct {
+	Members      []User                  `json:"members,omitempty"` // ListUsers
+	User         `json:"user,omitempty"` // GetUserInfo
+	UserPresence                         // GetUserPresence
+	SlackResponse
+}
+
+func userRequest(path string, values url.Values, debug bool) (*userResponseFull, error) {
+	response := &userResponseFull{}
+	err := post(path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// GetUserPresence will retrieve the current presence status of given user.
+func (api *Client) GetUserPresence(user string) (*UserPresence, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"user":  {user},
+	}
+	response, err := userRequest("users.getPresence", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.UserPresence, nil
+}
+
+// GetUserInfo will retrive the complete user information
+func (api *Client) GetUserInfo(user string) (*User, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"user":  {user},
+	}
+	response, err := userRequest("users.info", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return &response.User, nil
+}
+
+// GetUsers returns the list of users (with their detailed information)
+func (api *Client) GetUsers() ([]User, error) {
+	values := url.Values{
+		"token":    {api.config.token},
+		"presence": {"1"},
+	}
+	response, err := userRequest("users.list", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.Members, nil
+}
+
+// SetUserAsActive marks the currently authenticated user as active
+func (api *Client) SetUserAsActive() error {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	_, err := userRequest("users.setActive", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// SetUserPresence changes the currently authenticated user presence
+func (api *Client) SetUserPresence(presence string) error {
+	values := url.Values{
+		"token":    {api.config.token},
+		"presence": {presence},
+	}
+	_, err := userRequest("users.setPresence", values, api.debug)
+	if err != nil {
+		return err
+	}
+	return nil
+
+}
diff --git a/vendor/github.com/nlopes/slack/websocket.go b/vendor/github.com/nlopes/slack/websocket.go
new file mode 100644
index 00000000..6eb09263
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket.go
@@ -0,0 +1,93 @@
+package slack
+
+import (
+	"encoding/json"
+	"errors"
+	"time"
+
+	"golang.org/x/net/websocket"
+)
+
+const (
+	// MaxMessageTextLength is the current maximum message length in number of characters as defined here
+	// https://api.slack.com/rtm#limits
+	MaxMessageTextLength = 4000
+)
+
+// RTM represents a managed websocket connection. It also supports
+// all the methods of the `Client` type.
+//
+// Create this element with Client's NewRTM().
+type RTM struct {
+	idGen IDGenerator
+	pings map[int]time.Time
+
+	// Connection life-cycle
+	conn             *websocket.Conn
+	IncomingEvents   chan RTMEvent
+	outgoingMessages chan OutgoingMessage
+	killChannel      chan bool
+	forcePing        chan bool
+	rawEvents        chan json.RawMessage
+	wasIntentional   bool
+	isConnected      bool
+
+	// Client is the main API, embedded
+	Client
+	websocketURL string
+
+	// UserDetails upon connection
+	info *Info
+}
+
+// NewRTM returns a RTM, which provides a fully managed connection to
+// Slack's websocket-based Real-Time Messaging protocol.
+func newRTM(api *Client) *RTM {
+	return &RTM{
+		Client:           *api,
+		IncomingEvents:   make(chan RTMEvent, 50),
+		outgoingMessages: make(chan OutgoingMessage, 20),
+		pings:            make(map[int]time.Time),
+		isConnected:      false,
+		wasIntentional:   true,
+		killChannel:      make(chan bool),
+		forcePing:        make(chan bool),
+		rawEvents:        make(chan json.RawMessage),
+		idGen:            NewSafeID(1),
+	}
+}
+
+// Disconnect and wait, blocking until a successful disconnection.
+func (rtm *RTM) Disconnect() error {
+	if !rtm.isConnected {
+		return errors.New("Invalid call to Disconnect - Slack API is already disconnected")
+	}
+	rtm.killChannel <- true
+	return nil
+}
+
+// Reconnect only makes sense if you've successfully disconnectd with Disconnect().
+func (rtm *RTM) Reconnect() error {
+	logger.Println("RTM::Reconnect not implemented!")
+	return nil
+}
+
+// GetInfo returns the info structure received when calling
+// "startrtm", holding all channels, groups and other metadata needed
+// to implement a full chat client. It will be non-nil after a call to
+// StartRTM().
+func (rtm *RTM) GetInfo() *Info {
+	return rtm.info
+}
+
+// SendMessage submits a simple message through the websocket.  For
+// more complicated messages, use `rtm.PostMessage` with a complete
+// struct describing your attachments and all.
+func (rtm *RTM) SendMessage(msg *OutgoingMessage) {
+	if msg == nil {
+		rtm.Debugln("Error: Attempted to SendMessage(nil)")
+		return
+	}
+
+	rtm.outgoingMessages <- *msg
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_channels.go b/vendor/github.com/nlopes/slack/websocket_channels.go
new file mode 100644
index 00000000..7dd3319b
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_channels.go
@@ -0,0 +1,72 @@
+package slack
+
+// ChannelCreatedEvent represents the Channel created event
+type ChannelCreatedEvent struct {
+	Type           string             `json:"type"`
+	Channel        ChannelCreatedInfo `json:"channel"`
+	EventTimestamp string             `json:"event_ts"`
+}
+
+// ChannelCreatedInfo represents the information associated with the Channel created event
+type ChannelCreatedInfo struct {
+	ID        string `json:"id"`
+	IsChannel bool   `json:"is_channel"`
+	Name      string `json:"name"`
+	Created   int    `json:"created"`
+	Creator   string `json:"creator"`
+}
+
+// ChannelJoinedEvent represents the Channel joined event
+type ChannelJoinedEvent struct {
+	Type    string  `json:"type"`
+	Channel Channel `json:"channel"`
+}
+
+// ChannelInfoEvent represents the Channel info event
+type ChannelInfoEvent struct {
+	// channel_left
+	// channel_deleted
+	// channel_archive
+	// channel_unarchive
+	Type      string `json:"type"`
+	Channel   string `json:"channel"`
+	User      string `json:"user,omitempty"`
+	Timestamp string `json:"ts,omitempty"`
+}
+
+// ChannelRenameEvent represents the Channel rename event
+type ChannelRenameEvent struct {
+	Type      string            `json:"type"`
+	Channel   ChannelRenameInfo `json:"channel"`
+	Timestamp string            `json:"event_ts"`
+}
+
+// ChannelRenameInfo represents the information associated with a Channel rename event
+type ChannelRenameInfo struct {
+	ID      string `json:"id"`
+	Name    string `json:"name"`
+	Created string `json:"created"`
+}
+
+// ChannelHistoryChangedEvent represents the Channel history changed event
+type ChannelHistoryChangedEvent struct {
+	Type           string `json:"type"`
+	Latest         string `json:"latest"`
+	Timestamp      string `json:"ts"`
+	EventTimestamp string `json:"event_ts"`
+}
+
+// ChannelMarkedEvent represents the Channel marked event
+type ChannelMarkedEvent ChannelInfoEvent
+
+// ChannelLeftEvent represents the Channel left event
+type ChannelLeftEvent ChannelInfoEvent
+
+// ChannelDeletedEvent represents the Channel deleted event
+type ChannelDeletedEvent ChannelInfoEvent
+
+// ChannelArchiveEvent represents the Channel archive event
+type ChannelArchiveEvent ChannelInfoEvent
+
+// ChannelUnarchiveEvent represents the Channel unarchive event
+type ChannelUnarchiveEvent ChannelInfoEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_dm.go b/vendor/github.com/nlopes/slack/websocket_dm.go
new file mode 100644
index 00000000..98bf6f88
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_dm.go
@@ -0,0 +1,23 @@
+package slack
+
+// IMCreatedEvent represents the IM created event
+type IMCreatedEvent struct {
+	Type    string             `json:"type"`
+	User    string             `json:"user"`
+	Channel ChannelCreatedInfo `json:"channel"`
+}
+
+// IMHistoryChangedEvent represents the IM history changed event
+type IMHistoryChangedEvent ChannelHistoryChangedEvent
+
+// IMOpenEvent represents the IM open event
+type IMOpenEvent ChannelInfoEvent
+
+// IMCloseEvent represents the IM close event
+type IMCloseEvent ChannelInfoEvent
+
+// IMMarkedEvent represents the IM marked event
+type IMMarkedEvent ChannelInfoEvent
+
+// IMMarkedHistoryChanged represents the IM marked history changed event
+type IMMarkedHistoryChanged ChannelInfoEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_dnd.go b/vendor/github.com/nlopes/slack/websocket_dnd.go
new file mode 100644
index 00000000..62ddea3a
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_dnd.go
@@ -0,0 +1,8 @@
+package slack
+
+// DNDUpdatedEvent represents the update event for Do Not Disturb
+type DNDUpdatedEvent struct {
+	Type   string    `json:"type"`
+	User   string    `json:"user"`
+	Status DNDStatus `json:"dnd_status"`
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_files.go b/vendor/github.com/nlopes/slack/websocket_files.go
new file mode 100644
index 00000000..8c5bd4f8
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_files.go
@@ -0,0 +1,49 @@
+package slack
+
+// FileActionEvent represents the File action event
+type fileActionEvent struct {
+	Type           string `json:"type"`
+	EventTimestamp string `json:"event_ts"`
+	File           File   `json:"file"`
+	// FileID is used for FileDeletedEvent
+	FileID string `json:"file_id,omitempty"`
+}
+
+// FileCreatedEvent represents the File created event
+type FileCreatedEvent fileActionEvent
+
+// FileSharedEvent represents the File shared event
+type FileSharedEvent fileActionEvent
+
+// FilePublicEvent represents the File public event
+type FilePublicEvent fileActionEvent
+
+// FileUnsharedEvent represents the File unshared event
+type FileUnsharedEvent fileActionEvent
+
+// FileChangeEvent represents the File change event
+type FileChangeEvent fileActionEvent
+
+// FileDeletedEvent represents the File deleted event
+type FileDeletedEvent fileActionEvent
+
+// FilePrivateEvent represents the File private event
+type FilePrivateEvent fileActionEvent
+
+// FileCommentAddedEvent represents the File comment added event
+type FileCommentAddedEvent struct {
+	fileActionEvent
+	Comment Comment `json:"comment"`
+}
+
+// FileCommentEditedEvent represents the File comment edited event
+type FileCommentEditedEvent struct {
+	fileActionEvent
+	Comment Comment `json:"comment"`
+}
+
+// FileCommentDeletedEvent represents the File comment deleted event
+type FileCommentDeletedEvent struct {
+	fileActionEvent
+	Comment string `json:"comment"`
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_groups.go b/vendor/github.com/nlopes/slack/websocket_groups.go
new file mode 100644
index 00000000..eb88985c
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_groups.go
@@ -0,0 +1,49 @@
+package slack
+
+// GroupCreatedEvent represents the Group created event
+type GroupCreatedEvent struct {
+	Type    string             `json:"type"`
+	User    string             `json:"user"`
+	Channel ChannelCreatedInfo `json:"channel"`
+}
+
+// XXX: Should we really do this? event.Group is probably nicer than event.Channel
+// even though the api returns "channel"
+
+// GroupMarkedEvent represents the Group marked event
+type GroupMarkedEvent ChannelInfoEvent
+
+// GroupOpenEvent represents the Group open event
+type GroupOpenEvent ChannelInfoEvent
+
+// GroupCloseEvent represents the Group close event
+type GroupCloseEvent ChannelInfoEvent
+
+// GroupArchiveEvent represents the Group archive event
+type GroupArchiveEvent ChannelInfoEvent
+
+// GroupUnarchiveEvent represents the Group unarchive event
+type GroupUnarchiveEvent ChannelInfoEvent
+
+// GroupLeftEvent represents the Group left event
+type GroupLeftEvent ChannelInfoEvent
+
+// GroupJoinedEvent represents the Group joined event
+type GroupJoinedEvent ChannelJoinedEvent
+
+// GroupRenameEvent represents the Group rename event
+type GroupRenameEvent struct {
+	Type      string          `json:"type"`
+	Group     GroupRenameInfo `json:"channel"`
+	Timestamp string          `json:"ts"`
+}
+
+// GroupRenameInfo represents the group info related to the renamed group
+type GroupRenameInfo struct {
+	ID      string `json:"id"`
+	Name    string `json:"name"`
+	Created string `json:"created"`
+}
+
+// GroupHistoryChangedEvent represents the Group history changed event
+type GroupHistoryChangedEvent ChannelHistoryChangedEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_internals.go b/vendor/github.com/nlopes/slack/websocket_internals.go
new file mode 100644
index 00000000..2a8abe6e
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_internals.go
@@ -0,0 +1,92 @@
+package slack
+
+import (
+	"fmt"
+	"time"
+)
+
+/**
+ * Internal events, created by this lib and not mapped to Slack APIs.
+ */
+
+// ConnectedEvent is used for when we connect to Slack
+type ConnectedEvent struct {
+	ConnectionCount int // 1 = first time, 2 = second time
+	Info            *Info
+}
+
+// ConnectionErrorEvent contains information about a connection error
+type ConnectionErrorEvent struct {
+	Attempt  int
+	ErrorObj error
+}
+
+func (c *ConnectionErrorEvent) Error() string {
+	return c.ErrorObj.Error()
+}
+
+// ConnectingEvent contains information about our connection attempt
+type ConnectingEvent struct {
+	Attempt         int // 1 = first attempt, 2 = second attempt
+	ConnectionCount int
+}
+
+// DisconnectedEvent contains information about how we disconnected
+type DisconnectedEvent struct {
+	Intentional bool
+}
+
+// LatencyReport contains information about connection latency
+type LatencyReport struct {
+	Value time.Duration
+}
+
+// InvalidAuthEvent is used in case we can't even authenticate with the API
+type InvalidAuthEvent struct{}
+
+// UnmarshallingErrorEvent is used when there are issues deconstructing a response
+type UnmarshallingErrorEvent struct {
+	ErrorObj error
+}
+
+func (u UnmarshallingErrorEvent) Error() string {
+	return u.ErrorObj.Error()
+}
+
+// MessageTooLongEvent is used when sending a message that is too long
+type MessageTooLongEvent struct {
+	Message   OutgoingMessage
+	MaxLength int
+}
+
+func (m *MessageTooLongEvent) Error() string {
+	return fmt.Sprintf("Message too long (max %d characters)", m.MaxLength)
+}
+
+// OutgoingErrorEvent contains information in case there were errors sending messages
+type OutgoingErrorEvent struct {
+	Message  OutgoingMessage
+	ErrorObj error
+}
+
+func (o OutgoingErrorEvent) Error() string {
+	return o.ErrorObj.Error()
+}
+
+// IncomingEventError contains information about an unexpected error receiving a websocket event
+type IncomingEventError struct {
+	ErrorObj error
+}
+
+func (i *IncomingEventError) Error() string {
+	return i.ErrorObj.Error()
+}
+
+// AckErrorEvent i
+type AckErrorEvent struct {
+	ErrorObj error
+}
+
+func (a *AckErrorEvent) Error() string {
+	return a.ErrorObj.Error()
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_managed_conn.go b/vendor/github.com/nlopes/slack/websocket_managed_conn.go
new file mode 100644
index 00000000..db2df902
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_managed_conn.go
@@ -0,0 +1,427 @@
+package slack
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"reflect"
+	"time"
+
+	"golang.org/x/net/websocket"
+)
+
+// ManageConnection can be called on a Slack RTM instance returned by the
+// NewRTM method. It will connect to the slack RTM API and handle all incoming
+// and outgoing events. If a connection fails then it will attempt to reconnect
+// and will notify any listeners through an error event on the IncomingEvents
+// channel.
+//
+// If the connection ends and the disconnect was unintentional then this will
+// attempt to reconnect.
+//
+// This should only be called once per slack API! Otherwise expect undefined
+// behavior.
+//
+// The defined error events are located in websocket_internals.go.
+func (rtm *RTM) ManageConnection() {
+	var connectionCount int
+	for {
+		connectionCount++
+		// start trying to connect
+		// the returned err is already passed onto the IncomingEvents channel
+		info, conn, err := rtm.connect(connectionCount)
+		// if err != nil then the connection is sucessful - otherwise it is
+		// fatal
+		if err != nil {
+			return
+		}
+		rtm.info = info
+		rtm.IncomingEvents <- RTMEvent{"connected", &ConnectedEvent{
+			ConnectionCount: connectionCount,
+			Info:            info,
+		}}
+
+		rtm.conn = conn
+		rtm.isConnected = true
+
+		keepRunning := make(chan bool)
+		// we're now connected (or have failed fatally) so we can set up
+		// listeners
+		go rtm.handleIncomingEvents(keepRunning)
+
+		// this should be a blocking call until the connection has ended
+		rtm.handleEvents(keepRunning, 30*time.Second)
+
+		// after being disconnected we need to check if it was intentional
+		// if not then we should try to reconnect
+		if rtm.wasIntentional {
+			return
+		}
+		// else continue and run the loop again to connect
+	}
+}
+
+// connect attempts to connect to the slack websocket API. It handles any
+// errors that occur while connecting and will return once a connection
+// has been successfully opened.
+func (rtm *RTM) connect(connectionCount int) (*Info, *websocket.Conn, error) {
+	// used to provide exponential backoff wait time with jitter before trying
+	// to connect to slack again
+	boff := &backoff{
+		Min:    100 * time.Millisecond,
+		Max:    5 * time.Minute,
+		Factor: 2,
+		Jitter: true,
+	}
+
+	for {
+		// send connecting event
+		rtm.IncomingEvents <- RTMEvent{"connecting", &ConnectingEvent{
+			Attempt:         boff.attempts + 1,
+			ConnectionCount: connectionCount,
+		}}
+		// attempt to start the connection
+		info, conn, err := rtm.startRTMAndDial()
+		if err == nil {
+			return info, conn, nil
+		}
+		// check for fatal errors - currently only invalid_auth
+		if sErr, ok := err.(*WebError); ok && (sErr.Error() == "invalid_auth" || sErr.Error() == "account_inactive") {
+			rtm.IncomingEvents <- RTMEvent{"invalid_auth", &InvalidAuthEvent{}}
+			return nil, nil, sErr
+		}
+		// any other errors are treated as recoverable and we try again after
+		// sending the event along the IncomingEvents channel
+		rtm.IncomingEvents <- RTMEvent{"connection_error", &ConnectionErrorEvent{
+			Attempt:  boff.attempts,
+			ErrorObj: err,
+		}}
+		// get time we should wait before attempting to connect again
+		dur := boff.Duration()
+		rtm.Debugf("reconnection %d failed: %s", boff.attempts+1, err)
+		rtm.Debugln(" -> reconnecting in", dur)
+		time.Sleep(dur)
+	}
+}
+
+// startRTMAndDial attemps to connect to the slack websocket. It returns the
+// full information returned by the "rtm.start" method on the slack API.
+func (rtm *RTM) startRTMAndDial() (*Info, *websocket.Conn, error) {
+	info, url, err := rtm.StartRTM()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	conn, err := websocketProxyDial(url, "http://api.slack.com")
+	if err != nil {
+		return nil, nil, err
+	}
+	return info, conn, err
+}
+
+// killConnection stops the websocket connection and signals to all goroutines
+// that they should cease listening to the connection for events.
+//
+// This should not be called directly! Instead a boolean value (true for
+// intentional, false otherwise) should be sent to the killChannel on the RTM.
+func (rtm *RTM) killConnection(keepRunning chan bool, intentional bool) error {
+	rtm.Debugln("killing connection")
+	if rtm.isConnected {
+		close(keepRunning)
+	}
+	rtm.isConnected = false
+	rtm.wasIntentional = intentional
+	err := rtm.conn.Close()
+	rtm.IncomingEvents <- RTMEvent{"disconnected", &DisconnectedEvent{intentional}}
+	return err
+}
+
+// handleEvents is a blocking function that handles all events. This sends
+// pings when asked to (on rtm.forcePing) and upon every given elapsed
+// interval. This also sends outgoing messages that are received from the RTM's
+// outgoingMessages channel. This also handles incoming raw events from the RTM
+// rawEvents channel.
+func (rtm *RTM) handleEvents(keepRunning chan bool, interval time.Duration) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	for {
+		select {
+		// catch "stop" signal on channel close
+		case intentional := <-rtm.killChannel:
+			_ = rtm.killConnection(keepRunning, intentional)
+			return
+			// send pings on ticker interval
+		case <-ticker.C:
+			err := rtm.ping()
+			if err != nil {
+				_ = rtm.killConnection(keepRunning, false)
+				return
+			}
+		case <-rtm.forcePing:
+			err := rtm.ping()
+			if err != nil {
+				_ = rtm.killConnection(keepRunning, false)
+				return
+			}
+		// listen for messages that need to be sent
+		case msg := <-rtm.outgoingMessages:
+			rtm.sendOutgoingMessage(msg)
+		// listen for incoming messages that need to be parsed
+		case rawEvent := <-rtm.rawEvents:
+			rtm.handleRawEvent(rawEvent)
+		}
+	}
+}
+
+// handleIncomingEvents monitors the RTM's opened websocket for any incoming
+// events. It pushes the raw events onto the RTM channel rawEvents.
+//
+// This will stop executing once the RTM's keepRunning channel has been closed
+// or has anything sent to it.
+func (rtm *RTM) handleIncomingEvents(keepRunning <-chan bool) {
+	for {
+		// non-blocking listen to see if channel is closed
+		select {
+		// catch "stop" signal on channel close
+		case <-keepRunning:
+			return
+		default:
+			rtm.receiveIncomingEvent()
+		}
+	}
+}
+
+// sendOutgoingMessage sends the given OutgoingMessage to the slack websocket.
+//
+// It does not currently detect if a outgoing message fails due to a disconnect
+// and instead lets a future failed 'PING' detect the failed connection.
+func (rtm *RTM) sendOutgoingMessage(msg OutgoingMessage) {
+	rtm.Debugln("Sending message:", msg)
+	if len(msg.Text) > MaxMessageTextLength {
+		rtm.IncomingEvents <- RTMEvent{"outgoing_error", &MessageTooLongEvent{
+			Message:   msg,
+			MaxLength: MaxMessageTextLength,
+		}}
+		return
+	}
+	err := websocket.JSON.Send(rtm.conn, msg)
+	if err != nil {
+		rtm.IncomingEvents <- RTMEvent{"outgoing_error", &OutgoingErrorEvent{
+			Message:  msg,
+			ErrorObj: err,
+		}}
+		// TODO force ping?
+	}
+}
+
+// ping sends a 'PING' message to the RTM's websocket. If the 'PING' message
+// fails to send then this returns an error signifying that the connection
+// should be considered disconnected.
+//
+// This does not handle incoming 'PONG' responses but does store the time of
+// each successful 'PING' send so latency can be detected upon a 'PONG'
+// response.
+func (rtm *RTM) ping() error {
+	id := rtm.idGen.Next()
+	rtm.Debugln("Sending PING ", id)
+	rtm.pings[id] = time.Now()
+
+	msg := &Ping{ID: id, Type: "ping"}
+	err := websocket.JSON.Send(rtm.conn, msg)
+	if err != nil {
+		rtm.Debugf("RTM Error sending 'PING %d': %s", id, err.Error())
+		return err
+	}
+	return nil
+}
+
+// receiveIncomingEvent attempts to receive an event from the RTM's websocket.
+// This will block until a frame is available from the websocket.
+func (rtm *RTM) receiveIncomingEvent() {
+	event := json.RawMessage{}
+	err := websocket.JSON.Receive(rtm.conn, &event)
+	if err == io.EOF {
+		// EOF's don't seem to signify a failed connection so instead we ignore
+		// them here and detect a failed connection upon attempting to send a
+		// 'PING' message
+
+		// trigger a 'PING' to detect pontential websocket disconnect
+		rtm.forcePing <- true
+		return
+	} else if err != nil {
+		rtm.IncomingEvents <- RTMEvent{"incoming_error", &IncomingEventError{
+			ErrorObj: err,
+		}}
+		// force a ping here too?
+		return
+	} else if len(event) == 0 {
+		rtm.Debugln("Received empty event")
+		return
+	}
+	rtm.Debugln("Incoming Event:", string(event[:]))
+	rtm.rawEvents <- event
+}
+
+// handleRawEvent takes a raw JSON message received from the slack websocket
+// and handles the encoded event.
+func (rtm *RTM) handleRawEvent(rawEvent json.RawMessage) {
+	event := &Event{}
+	err := json.Unmarshal(rawEvent, event)
+	if err != nil {
+		rtm.IncomingEvents <- RTMEvent{"unmarshalling_error", &UnmarshallingErrorEvent{err}}
+		return
+	}
+	switch event.Type {
+	case "":
+		rtm.handleAck(rawEvent)
+	case "hello":
+		rtm.IncomingEvents <- RTMEvent{"hello", &HelloEvent{}}
+	case "pong":
+		rtm.handlePong(rawEvent)
+	default:
+		rtm.handleEvent(event.Type, rawEvent)
+	}
+}
+
+// handleAck handles an incoming 'ACK' message.
+func (rtm *RTM) handleAck(event json.RawMessage) {
+	ack := &AckMessage{}
+	if err := json.Unmarshal(event, ack); err != nil {
+		rtm.Debugln("RTM Error unmarshalling 'ack' event:", err)
+		rtm.Debugln(" -> Erroneous 'ack' event:", string(event))
+		return
+	}
+	if ack.Ok {
+		rtm.IncomingEvents <- RTMEvent{"ack", ack}
+	} else {
+		rtm.IncomingEvents <- RTMEvent{"ack_error", &AckErrorEvent{ack.Error}}
+	}
+}
+
+// handlePong handles an incoming 'PONG' message which should be in response to
+// a previously sent 'PING' message. This is then used to compute the
+// connection's latency.
+func (rtm *RTM) handlePong(event json.RawMessage) {
+	pong := &Pong{}
+	if err := json.Unmarshal(event, pong); err != nil {
+		rtm.Debugln("RTM Error unmarshalling 'pong' event:", err)
+		rtm.Debugln(" -> Erroneous 'ping' event:", string(event))
+		return
+	}
+	if pingTime, exists := rtm.pings[pong.ReplyTo]; exists {
+		latency := time.Since(pingTime)
+		rtm.IncomingEvents <- RTMEvent{"latency_report", &LatencyReport{Value: latency}}
+		delete(rtm.pings, pong.ReplyTo)
+	} else {
+		rtm.Debugln("RTM Error - unmatched 'pong' event:", string(event))
+	}
+}
+
+// handleEvent is the "default" response to an event that does not have a
+// special case. It matches the command's name to a mapping of defined events
+// and then sends the corresponding event struct to the IncomingEvents channel.
+// If the event type is not found or the event cannot be unmarshalled into the
+// correct struct then this sends an UnmarshallingErrorEvent to the
+// IncomingEvents channel.
+func (rtm *RTM) handleEvent(typeStr string, event json.RawMessage) {
+	v, exists := eventMapping[typeStr]
+	if !exists {
+		rtm.Debugf("RTM Error, received unmapped event %q: %s\n", typeStr, string(event))
+		err := fmt.Errorf("RTM Error: Received unmapped event %q: %s\n", typeStr, string(event))
+		rtm.IncomingEvents <- RTMEvent{"unmarshalling_error", &UnmarshallingErrorEvent{err}}
+		return
+	}
+	t := reflect.TypeOf(v)
+	recvEvent := reflect.New(t).Interface()
+	err := json.Unmarshal(event, recvEvent)
+	if err != nil {
+		rtm.Debugf("RTM Error, could not unmarshall event %q: %s\n", typeStr, string(event))
+		err := fmt.Errorf("RTM Error: Could not unmarshall event %q: %s\n", typeStr, string(event))
+		rtm.IncomingEvents <- RTMEvent{"unmarshalling_error", &UnmarshallingErrorEvent{err}}
+		return
+	}
+	rtm.IncomingEvents <- RTMEvent{typeStr, recvEvent}
+}
+
+// eventMapping holds a mapping of event names to their corresponding struct
+// implementations. The structs should be instances of the unmarshalling
+// target for the matching event type.
+var eventMapping = map[string]interface{}{
+	"message":         MessageEvent{},
+	"presence_change": PresenceChangeEvent{},
+	"user_typing":     UserTypingEvent{},
+
+	"channel_marked":          ChannelMarkedEvent{},
+	"channel_created":         ChannelCreatedEvent{},
+	"channel_joined":          ChannelJoinedEvent{},
+	"channel_left":            ChannelLeftEvent{},
+	"channel_deleted":         ChannelDeletedEvent{},
+	"channel_rename":          ChannelRenameEvent{},
+	"channel_archive":         ChannelArchiveEvent{},
+	"channel_unarchive":       ChannelUnarchiveEvent{},
+	"channel_history_changed": ChannelHistoryChangedEvent{},
+
+	"dnd_updated":      DNDUpdatedEvent{},
+	"dnd_updated_user": DNDUpdatedEvent{},
+
+	"im_created":         IMCreatedEvent{},
+	"im_open":            IMOpenEvent{},
+	"im_close":           IMCloseEvent{},
+	"im_marked":          IMMarkedEvent{},
+	"im_history_changed": IMHistoryChangedEvent{},
+
+	"group_marked":          GroupMarkedEvent{},
+	"group_open":            GroupOpenEvent{},
+	"group_joined":          GroupJoinedEvent{},
+	"group_left":            GroupLeftEvent{},
+	"group_close":           GroupCloseEvent{},
+	"group_rename":          GroupRenameEvent{},
+	"group_archive":         GroupArchiveEvent{},
+	"group_unarchive":       GroupUnarchiveEvent{},
+	"group_history_changed": GroupHistoryChangedEvent{},
+
+	"file_created":         FileCreatedEvent{},
+	"file_shared":          FileSharedEvent{},
+	"file_unshared":        FileUnsharedEvent{},
+	"file_public":          FilePublicEvent{},
+	"file_private":         FilePrivateEvent{},
+	"file_change":          FileChangeEvent{},
+	"file_deleted":         FileDeletedEvent{},
+	"file_comment_added":   FileCommentAddedEvent{},
+	"file_comment_edited":  FileCommentEditedEvent{},
+	"file_comment_deleted": FileCommentDeletedEvent{},
+
+	"pin_added":   PinAddedEvent{},
+	"pin_removed": PinRemovedEvent{},
+
+	"star_added":   StarAddedEvent{},
+	"star_removed": StarRemovedEvent{},
+
+	"reaction_added":   ReactionAddedEvent{},
+	"reaction_removed": ReactionRemovedEvent{},
+
+	"pref_change": PrefChangeEvent{},
+
+	"team_join":              TeamJoinEvent{},
+	"team_rename":            TeamRenameEvent{},
+	"team_pref_change":       TeamPrefChangeEvent{},
+	"team_domain_change":     TeamDomainChangeEvent{},
+	"team_migration_started": TeamMigrationStartedEvent{},
+
+	"manual_presence_change": ManualPresenceChangeEvent{},
+
+	"user_change": UserChangeEvent{},
+
+	"emoji_changed": EmojiChangedEvent{},
+
+	"commands_changed": CommandsChangedEvent{},
+
+	"email_domain_changed": EmailDomainChangedEvent{},
+
+	"bot_added":   BotAddedEvent{},
+	"bot_changed": BotChangedEvent{},
+
+	"accounts_changed": AccountsChangedEvent{},
+
+	"reconnect_url": ReconnectUrlEvent{},
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_misc.go b/vendor/github.com/nlopes/slack/websocket_misc.go
new file mode 100644
index 00000000..6c2c6abf
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_misc.go
@@ -0,0 +1,117 @@
+package slack
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+// AckMessage is used for messages received in reply to other messages
+type AckMessage struct {
+	ReplyTo   int    `json:"reply_to"`
+	Timestamp string `json:"ts"`
+	Text      string `json:"text"`
+	RTMResponse
+}
+
+// RTMResponse encapsulates response details as returned by the Slack API
+type RTMResponse struct {
+	Ok    bool      `json:"ok"`
+	Error *RTMError `json:"error"`
+}
+
+// RTMError encapsulates error information as returned by the Slack API
+type RTMError struct {
+	Code int
+	Msg  string
+}
+
+func (s RTMError) Error() string {
+	return fmt.Sprintf("Code %d - %s", s.Code, s.Msg)
+}
+
+// MessageEvent represents a Slack Message (used as the event type for an incoming message)
+type MessageEvent Message
+
+// RTMEvent is the main wrapper. You will find all the other messages attached
+type RTMEvent struct {
+	Type string
+	Data interface{}
+}
+
+// HelloEvent represents the hello event
+type HelloEvent struct{}
+
+// PresenceChangeEvent represents the presence change event
+type PresenceChangeEvent struct {
+	Type     string `json:"type"`
+	Presence string `json:"presence"`
+	User     string `json:"user"`
+}
+
+// UserTypingEvent represents the user typing event
+type UserTypingEvent struct {
+	Type    string `json:"type"`
+	User    string `json:"user"`
+	Channel string `json:"channel"`
+}
+
+// PrefChangeEvent represents a user preferences change event
+type PrefChangeEvent struct {
+	Type  string          `json:"type"`
+	Name  string          `json:"name"`
+	Value json.RawMessage `json:"value"`
+}
+
+// ManualPresenceChangeEvent represents the manual presence change event
+type ManualPresenceChangeEvent struct {
+	Type     string `json:"type"`
+	Presence string `json:"presence"`
+}
+
+// UserChangeEvent represents the user change event
+type UserChangeEvent struct {
+	Type string `json:"type"`
+	User User   `json:"user"`
+}
+
+// EmojiChangedEvent represents the emoji changed event
+type EmojiChangedEvent struct {
+	Type           string `json:"type"`
+	EventTimestamp string `json:"event_ts"`
+}
+
+// CommandsChangedEvent represents the commands changed event
+type CommandsChangedEvent struct {
+	Type           string `json:"type"`
+	EventTimestamp string `json:"event_ts"`
+}
+
+// EmailDomainChangedEvent represents the email domain changed event
+type EmailDomainChangedEvent struct {
+	Type           string `json:"type"`
+	EventTimestamp string `json:"event_ts"`
+	EmailDomain    string `json:"email_domain"`
+}
+
+// BotAddedEvent represents the bot added event
+type BotAddedEvent struct {
+	Type string `json:"type"`
+	Bot  Bot    `json:"bot"`
+}
+
+// BotChangedEvent represents the bot changed event
+type BotChangedEvent struct {
+	Type string `json:"type"`
+	Bot  Bot    `json:"bot"`
+}
+
+// AccountsChangedEvent represents the accounts changed event
+type AccountsChangedEvent struct {
+	Type string `json:"type"`
+}
+
+// ReconnectUrlEvent represents the receiving reconnect url event
+type ReconnectUrlEvent struct {
+	Type string `json:"type"`
+	URL  string `json:"url"`
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_pins.go b/vendor/github.com/nlopes/slack/websocket_pins.go
new file mode 100644
index 00000000..95445e28
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_pins.go
@@ -0,0 +1,16 @@
+package slack
+
+type pinEvent struct {
+	Type           string `json:"type"`
+	User           string `json:"user"`
+	Item           Item   `json:"item"`
+	Channel        string `json:"channel_id"`
+	EventTimestamp string `json:"event_ts"`
+	HasPins        bool   `json:"has_pins,omitempty"`
+}
+
+// PinAddedEvent represents the Pin added event
+type PinAddedEvent pinEvent
+
+// PinRemovedEvent represents the Pin removed event
+type PinRemovedEvent pinEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_proxy.go b/vendor/github.com/nlopes/slack/websocket_proxy.go
new file mode 100644
index 00000000..440015d6
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_proxy.go
@@ -0,0 +1,83 @@
+package slack
+
+import (
+	"crypto/tls"
+	"errors"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"os"
+	"strings"
+
+	"golang.org/x/net/websocket"
+)
+
+// Taken and reworked from: https://gist.github.com/madmo/8548738
+func websocketHTTPConnect(proxy, urlString string) (net.Conn, error) {
+	p, err := net.Dial("tcp", proxy)
+	if err != nil {
+		return nil, err
+	}
+
+	turl, err := url.Parse(urlString)
+	if err != nil {
+		return nil, err
+	}
+
+	req := http.Request{
+		Method: "CONNECT",
+		URL:    &url.URL{},
+		Host:   turl.Host,
+	}
+
+	cc := httputil.NewProxyClientConn(p, nil)
+	cc.Do(&req)
+	if err != nil && err != httputil.ErrPersistEOF {
+		return nil, err
+	}
+
+	rwc, _ := cc.Hijack()
+
+	return rwc, nil
+}
+
+func websocketProxyDial(urlString, origin string) (ws *websocket.Conn, err error) {
+	if os.Getenv("HTTP_PROXY") == "" {
+		return websocket.Dial(urlString, "", origin)
+	}
+
+	purl, err := url.Parse(os.Getenv("HTTP_PROXY"))
+	if err != nil {
+		return nil, err
+	}
+
+	config, err := websocket.NewConfig(urlString, origin)
+	if err != nil {
+		return nil, err
+	}
+
+	client, err := websocketHTTPConnect(purl.Host, urlString)
+	if err != nil {
+		return nil, err
+	}
+
+	switch config.Location.Scheme {
+	case "ws":
+	case "wss":
+		tlsClient := tls.Client(client, &tls.Config{
+			ServerName: strings.Split(config.Location.Host, ":")[0],
+		})
+		err := tlsClient.Handshake()
+		if err != nil {
+			tlsClient.Close()
+			return nil, err
+		}
+		client = tlsClient
+
+	default:
+		return nil, errors.New("invalid websocket schema")
+	}
+
+	return websocket.NewClient(config, client)
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_reactions.go b/vendor/github.com/nlopes/slack/websocket_reactions.go
new file mode 100644
index 00000000..e4973878
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_reactions.go
@@ -0,0 +1,25 @@
+package slack
+
+// reactionItem is a lighter-weight item than is returned by the reactions list.
+type reactionItem struct {
+	Type        string `json:"type"`
+	Channel     string `json:"channel,omitempty"`
+	File        string `json:"file,omitempty"`
+	FileComment string `json:"file_comment,omitempty"`
+	Timestamp   string `json:"ts,omitempty"`
+}
+
+type reactionEvent struct {
+	Type           string       `json:"type"`
+	User           string       `json:"user"`
+	ItemUser       string       `json:"item_user"`
+	Item           reactionItem `json:"item"`
+	Reaction       string       `json:"reaction"`
+	EventTimestamp string       `json:"event_ts"`
+}
+
+// ReactionAddedEvent represents the Reaction added event
+type ReactionAddedEvent reactionEvent
+
+// ReactionRemovedEvent represents the Reaction removed event
+type ReactionRemovedEvent reactionEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_stars.go b/vendor/github.com/nlopes/slack/websocket_stars.go
new file mode 100644
index 00000000..e0f2dda3
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_stars.go
@@ -0,0 +1,14 @@
+package slack
+
+type starEvent struct {
+	Type           string      `json:"type"`
+	User           string      `json:"user"`
+	Item           StarredItem `json:"item"`
+	EventTimestamp string      `json:"event_ts"`
+}
+
+// StarAddedEvent represents the Star added event
+type StarAddedEvent starEvent
+
+// StarRemovedEvent represents the Star removed event
+type StarRemovedEvent starEvent
diff --git a/vendor/github.com/nlopes/slack/websocket_teams.go b/vendor/github.com/nlopes/slack/websocket_teams.go
new file mode 100644
index 00000000..3898c833
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_teams.go
@@ -0,0 +1,33 @@
+package slack
+
+// TeamJoinEvent represents the Team join event
+type TeamJoinEvent struct {
+	Type string `json:"type"`
+	User User   `json:"user"`
+}
+
+// TeamRenameEvent represents the Team rename event
+type TeamRenameEvent struct {
+	Type           string `json:"type"`
+	Name           string `json:"name,omitempty"`
+	EventTimestamp string `json:"event_ts,omitempty"`
+}
+
+// TeamPrefChangeEvent represents the Team preference change event
+type TeamPrefChangeEvent struct {
+	Type  string   `json:"type"`
+	Name  string   `json:"name,omitempty"`
+	Value []string `json:"value,omitempty"`
+}
+
+// TeamDomainChangeEvent represents the Team domain change event
+type TeamDomainChangeEvent struct {
+	Type   string `json:"type"`
+	URL    string `json:"url"`
+	Domain string `json:"domain"`
+}
+
+// TeamMigrationStartedEvent represents the Team migration started event
+type TeamMigrationStartedEvent struct {
+	Type string `json:"type"`
+}
diff --git a/vendor/github.com/nlopes/slack/websocket_utils.go b/vendor/github.com/nlopes/slack/websocket_utils.go
new file mode 100644
index 00000000..b3d0ec89
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/websocket_utils.go
@@ -0,0 +1,20 @@
+package slack
+
+import (
+	"net"
+	"net/url"
+)
+
+var portMapping = map[string]string{"ws": "80", "wss": "443"}
+
+func websocketizeURLPort(orig string) (string, error) {
+	urlObj, err := url.ParseRequestURI(orig)
+	if err != nil {
+		return "", err
+	}
+	_, _, err = net.SplitHostPort(urlObj.Host)
+	if err != nil {
+		return urlObj.Scheme + "://" + urlObj.Host + ":" + portMapping[urlObj.Scheme] + urlObj.Path, nil
+	}
+	return orig, nil
+}
diff --git a/vendor/golang.org/x/net/websocket/LICENSE b/vendor/golang.org/x/net/websocket/LICENSE
new file mode 100644
index 00000000..6a66aea5
--- /dev/null
+++ b/vendor/golang.org/x/net/websocket/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/golang.org/x/net/websocket/client.go b/vendor/golang.org/x/net/websocket/client.go
new file mode 100644
index 00000000..20d1e1e3
--- /dev/null
+++ b/vendor/golang.org/x/net/websocket/client.go
@@ -0,0 +1,113 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"crypto/tls"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+)
+
+// DialError is an error that occurs while dialling a websocket server.
+type DialError struct {
+	*Config
+	Err error
+}
+
+func (e *DialError) Error() string {
+	return "websocket.Dial " + e.Config.Location.String() + ": " + e.Err.Error()
+}
+
+// NewConfig creates a new WebSocket config for client connection.
+func NewConfig(server, origin string) (config *Config, err error) {
+	config = new(Config)
+	config.Version = ProtocolVersionHybi13
+	config.Location, err = url.ParseRequestURI(server)
+	if err != nil {
+		return
+	}
+	config.Origin, err = url.ParseRequestURI(origin)
+	if err != nil {
+		return
+	}
+	config.Header = http.Header(make(map[string][]string))
+	return
+}
+
+// NewClient creates a new WebSocket client connection over rwc.
+func NewClient(config *Config, rwc io.ReadWriteCloser) (ws *Conn, err error) {
+	br := bufio.NewReader(rwc)
+	bw := bufio.NewWriter(rwc)
+	err = hybiClientHandshake(config, br, bw)
+	if err != nil {
+		return
+	}
+	buf := bufio.NewReadWriter(br, bw)
+	ws = newHybiClientConn(config, buf, rwc)
+	return
+}
+
+// Dial opens a new client connection to a WebSocket.
+func Dial(url_, protocol, origin string) (ws *Conn, err error) {
+	config, err := NewConfig(url_, origin)
+	if err != nil {
+		return nil, err
+	}
+	if protocol != "" {
+		config.Protocol = []string{protocol}
+	}
+	return DialConfig(config)
+}
+
+var portMap = map[string]string{
+	"ws":  "80",
+	"wss": "443",
+}
+
+func parseAuthority(location *url.URL) string {
+	if _, ok := portMap[location.Scheme]; ok {
+		if _, _, err := net.SplitHostPort(location.Host); err != nil {
+			return net.JoinHostPort(location.Host, portMap[location.Scheme])
+		}
+	}
+	return location.Host
+}
+
+// DialConfig opens a new client connection to a WebSocket with a config.
+func DialConfig(config *Config) (ws *Conn, err error) {
+	var client net.Conn
+	if config.Location == nil {
+		return nil, &DialError{config, ErrBadWebSocketLocation}
+	}
+	if config.Origin == nil {
+		return nil, &DialError{config, ErrBadWebSocketOrigin}
+	}
+	switch config.Location.Scheme {
+	case "ws":
+		client, err = net.Dial("tcp", parseAuthority(config.Location))
+
+	case "wss":
+		client, err = tls.Dial("tcp", parseAuthority(config.Location), config.TlsConfig)
+
+	default:
+		err = ErrBadScheme
+	}
+	if err != nil {
+		goto Error
+	}
+
+	ws, err = NewClient(config, client)
+	if err != nil {
+		client.Close()
+		goto Error
+	}
+	return
+
+Error:
+	return nil, &DialError{config, err}
+}
diff --git a/vendor/golang.org/x/net/websocket/hybi.go b/vendor/golang.org/x/net/websocket/hybi.go
new file mode 100644
index 00000000..8cffdd16
--- /dev/null
+++ b/vendor/golang.org/x/net/websocket/hybi.go
@@ -0,0 +1,583 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+// This file implements a protocol of hybi draft.
+// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/base64"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+const (
+	websocketGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+
+	closeStatusNormal            = 1000
+	closeStatusGoingAway         = 1001
+	closeStatusProtocolError     = 1002
+	closeStatusUnsupportedData   = 1003
+	closeStatusFrameTooLarge     = 1004
+	closeStatusNoStatusRcvd      = 1005
+	closeStatusAbnormalClosure   = 1006
+	closeStatusBadMessageData    = 1007
+	closeStatusPolicyViolation   = 1008
+	closeStatusTooBigData        = 1009
+	closeStatusExtensionMismatch = 1010
+
+	maxControlFramePayloadLength = 125
+)
+
+var (
+	ErrBadMaskingKey         = &ProtocolError{"bad masking key"}
+	ErrBadPongMessage        = &ProtocolError{"bad pong message"}
+	ErrBadClosingStatus      = &ProtocolError{"bad closing status"}
+	ErrUnsupportedExtensions = &ProtocolError{"unsupported extensions"}
+	ErrNotImplemented        = &ProtocolError{"not implemented"}
+
+	handshakeHeader = map[string]bool{
+		"Host":                   true,
+		"Upgrade":                true,
+		"Connection":             true,
+		"Sec-Websocket-Key":      true,
+		"Sec-Websocket-Origin":   true,
+		"Sec-Websocket-Version":  true,
+		"Sec-Websocket-Protocol": true,
+		"Sec-Websocket-Accept":   true,
+	}
+)
+
+// A hybiFrameHeader is a frame header as defined in hybi draft.
+type hybiFrameHeader struct {
+	Fin        bool
+	Rsv        [3]bool
+	OpCode     byte
+	Length     int64
+	MaskingKey []byte
+
+	data *bytes.Buffer
+}
+
+// A hybiFrameReader is a reader for hybi frame.
+type hybiFrameReader struct {
+	reader io.Reader
+
+	header hybiFrameHeader
+	pos    int64
+	length int
+}
+
+func (frame *hybiFrameReader) Read(msg []byte) (n int, err error) {
+	n, err = frame.reader.Read(msg)
+	if frame.header.MaskingKey != nil {
+		for i := 0; i < n; i++ {
+			msg[i] = msg[i] ^ frame.header.MaskingKey[frame.pos%4]
+			frame.pos++
+		}
+	}
+	return n, err
+}
+
+func (frame *hybiFrameReader) PayloadType() byte { return frame.header.OpCode }
+
+func (frame *hybiFrameReader) HeaderReader() io.Reader {
+	if frame.header.data == nil {
+		return nil
+	}
+	if frame.header.data.Len() == 0 {
+		return nil
+	}
+	return frame.header.data
+}
+
+func (frame *hybiFrameReader) TrailerReader() io.Reader { return nil }
+
+func (frame *hybiFrameReader) Len() (n int) { return frame.length }
+
+// A hybiFrameReaderFactory creates new frame reader based on its frame type.
+type hybiFrameReaderFactory struct {
+	*bufio.Reader
+}
+
+// NewFrameReader reads a frame header from the connection, and creates new reader for the frame.
+// See Section 5.2 Base Framing protocol for detail.
+// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17#section-5.2
+func (buf hybiFrameReaderFactory) NewFrameReader() (frame frameReader, err error) {
+	hybiFrame := new(hybiFrameReader)
+	frame = hybiFrame
+	var header []byte
+	var b byte
+	// First byte. FIN/RSV1/RSV2/RSV3/OpCode(4bits)
+	b, err = buf.ReadByte()
+	if err != nil {
+		return
+	}
+	header = append(header, b)
+	hybiFrame.header.Fin = ((header[0] >> 7) & 1) != 0
+	for i := 0; i < 3; i++ {
+		j := uint(6 - i)
+		hybiFrame.header.Rsv[i] = ((header[0] >> j) & 1) != 0
+	}
+	hybiFrame.header.OpCode = header[0] & 0x0f
+
+	// Second byte. Mask/Payload len(7bits)
+	b, err = buf.ReadByte()
+	if err != nil {
+		return
+	}
+	header = append(header, b)
+	mask := (b & 0x80) != 0
+	b &= 0x7f
+	lengthFields := 0
+	switch {
+	case b <= 125: // Payload length 7bits.
+		hybiFrame.header.Length = int64(b)
+	case b == 126: // Payload length 7+16bits
+		lengthFields = 2
+	case b == 127: // Payload length 7+64bits
+		lengthFields = 8
+	}
+	for i := 0; i < lengthFields; i++ {
+		b, err = buf.ReadByte()
+		if err != nil {
+			return
+		}
+		if lengthFields == 8 && i == 0 { // MSB must be zero when 7+64 bits
+			b &= 0x7f
+		}
+		header = append(header, b)
+		hybiFrame.header.Length = hybiFrame.header.Length*256 + int64(b)
+	}
+	if mask {
+		// Masking key. 4 bytes.
+		for i := 0; i < 4; i++ {
+			b, err = buf.ReadByte()
+			if err != nil {
+				return
+			}
+			header = append(header, b)
+			hybiFrame.header.MaskingKey = append(hybiFrame.header.MaskingKey, b)
+		}
+	}
+	hybiFrame.reader = io.LimitReader(buf.Reader, hybiFrame.header.Length)
+	hybiFrame.header.data = bytes.NewBuffer(header)
+	hybiFrame.length = len(header) + int(hybiFrame.header.Length)
+	return
+}
+
+// A HybiFrameWriter is a writer for hybi frame.
+type hybiFrameWriter struct {
+	writer *bufio.Writer
+
+	header *hybiFrameHeader
+}
+
+func (frame *hybiFrameWriter) Write(msg []byte) (n int, err error) {
+	var header []byte
+	var b byte
+	if frame.header.Fin {
+		b |= 0x80
+	}
+	for i := 0; i < 3; i++ {
+		if frame.header.Rsv[i] {
+			j := uint(6 - i)
+			b |= 1 << j
+		}
+	}
+	b |= frame.header.OpCode
+	header = append(header, b)
+	if frame.header.MaskingKey != nil {
+		b = 0x80
+	} else {
+		b = 0
+	}
+	lengthFields := 0
+	length := len(msg)
+	switch {
+	case length <= 125:
+		b |= byte(length)
+	case length < 65536:
+		b |= 126
+		lengthFields = 2
+	default:
+		b |= 127
+		lengthFields = 8
+	}
+	header = append(header, b)
+	for i := 0; i < lengthFields; i++ {
+		j := uint((lengthFields - i - 1) * 8)
+		b = byte((length >> j) & 0xff)
+		header = append(header, b)
+	}
+	if frame.header.MaskingKey != nil {
+		if len(frame.header.MaskingKey) != 4 {
+			return 0, ErrBadMaskingKey
+		}
+		header = append(header, frame.header.MaskingKey...)
+		frame.writer.Write(header)
+		data := make([]byte, length)
+		for i := range data {
+			data[i] = msg[i] ^ frame.header.MaskingKey[i%4]
+		}
+		frame.writer.Write(data)
+		err = frame.writer.Flush()
+		return length, err
+	}
+	frame.writer.Write(header)
+	frame.writer.Write(msg)
+	err = frame.writer.Flush()
+	return length, err
+}
+
+func (frame *hybiFrameWriter) Close() error { return nil }
+
+type hybiFrameWriterFactory struct {
+	*bufio.Writer
+	needMaskingKey bool
+}
+
+func (buf hybiFrameWriterFactory) NewFrameWriter(payloadType byte) (frame frameWriter, err error) {
+	frameHeader := &hybiFrameHeader{Fin: true, OpCode: payloadType}
+	if buf.needMaskingKey {
+		frameHeader.MaskingKey, err = generateMaskingKey()
+		if err != nil {
+			return nil, err
+		}
+	}
+	return &hybiFrameWriter{writer: buf.Writer, header: frameHeader}, nil
+}
+
+type hybiFrameHandler struct {
+	conn        *Conn
+	payloadType byte
+}
+
+func (handler *hybiFrameHandler) HandleFrame(frame frameReader) (frameReader, error) {
+	if handler.conn.IsServerConn() {
+		// The client MUST mask all frames sent to the server.
+		if frame.(*hybiFrameReader).header.MaskingKey == nil {
+			handler.WriteClose(closeStatusProtocolError)
+			return nil, io.EOF
+		}
+	} else {
+		// The server MUST NOT mask all frames.
+		if frame.(*hybiFrameReader).header.MaskingKey != nil {
+			handler.WriteClose(closeStatusProtocolError)
+			return nil, io.EOF
+		}
+	}
+	if header := frame.HeaderReader(); header != nil {
+		io.Copy(ioutil.Discard, header)
+	}
+	switch frame.PayloadType() {
+	case ContinuationFrame:
+		frame.(*hybiFrameReader).header.OpCode = handler.payloadType
+	case TextFrame, BinaryFrame:
+		handler.payloadType = frame.PayloadType()
+	case CloseFrame:
+		return nil, io.EOF
+	case PingFrame, PongFrame:
+		b := make([]byte, maxControlFramePayloadLength)
+		n, err := io.ReadFull(frame, b)
+		if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
+			return nil, err
+		}
+		io.Copy(ioutil.Discard, frame)
+		if frame.PayloadType() == PingFrame {
+			if _, err := handler.WritePong(b[:n]); err != nil {
+				return nil, err
+			}
+		}
+		return nil, nil
+	}
+	return frame, nil
+}
+
+func (handler *hybiFrameHandler) WriteClose(status int) (err error) {
+	handler.conn.wio.Lock()
+	defer handler.conn.wio.Unlock()
+	w, err := handler.conn.frameWriterFactory.NewFrameWriter(CloseFrame)
+	if err != nil {
+		return err
+	}
+	msg := make([]byte, 2)
+	binary.BigEndian.PutUint16(msg, uint16(status))
+	_, err = w.Write(msg)
+	w.Close()
+	return err
+}
+
+func (handler *hybiFrameHandler) WritePong(msg []byte) (n int, err error) {
+	handler.conn.wio.Lock()
+	defer handler.conn.wio.Unlock()
+	w, err := handler.conn.frameWriterFactory.NewFrameWriter(PongFrame)
+	if err != nil {
+		return 0, err
+	}
+	n, err = w.Write(msg)
+	w.Close()
+	return n, err
+}
+
+// newHybiConn creates a new WebSocket connection speaking hybi draft protocol.
+func newHybiConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
+	if buf == nil {
+		br := bufio.NewReader(rwc)
+		bw := bufio.NewWriter(rwc)
+		buf = bufio.NewReadWriter(br, bw)
+	}
+	ws := &Conn{config: config, request: request, buf: buf, rwc: rwc,
+		frameReaderFactory: hybiFrameReaderFactory{buf.Reader},
+		frameWriterFactory: hybiFrameWriterFactory{
+			buf.Writer, request == nil},
+		PayloadType:        TextFrame,
+		defaultCloseStatus: closeStatusNormal}
+	ws.frameHandler = &hybiFrameHandler{conn: ws}
+	return ws
+}
+
+// generateMaskingKey generates a masking key for a frame.
+func generateMaskingKey() (maskingKey []byte, err error) {
+	maskingKey = make([]byte, 4)
+	if _, err = io.ReadFull(rand.Reader, maskingKey); err != nil {
+		return
+	}
+	return
+}
+
+// generateNonce generates a nonce consisting of a randomly selected 16-byte
+// value that has been base64-encoded.
+func generateNonce() (nonce []byte) {
+	key := make([]byte, 16)
+	if _, err := io.ReadFull(rand.Reader, key); err != nil {
+		panic(err)
+	}
+	nonce = make([]byte, 24)
+	base64.StdEncoding.Encode(nonce, key)
+	return
+}
+
+// removeZone removes IPv6 zone identifer from host.
+// E.g., "[fe80::1%en0]:8080" to "[fe80::1]:8080"
+func removeZone(host string) string {
+	if !strings.HasPrefix(host, "[") {
+		return host
+	}
+	i := strings.LastIndex(host, "]")
+	if i < 0 {
+		return host
+	}
+	j := strings.LastIndex(host[:i], "%")
+	if j < 0 {
+		return host
+	}
+	return host[:j] + host[i:]
+}
+
+// getNonceAccept computes the base64-encoded SHA-1 of the concatenation of
+// the nonce ("Sec-WebSocket-Key" value) with the websocket GUID string.
+func getNonceAccept(nonce []byte) (expected []byte, err error) {
+	h := sha1.New()
+	if _, err = h.Write(nonce); err != nil {
+		return
+	}
+	if _, err = h.Write([]byte(websocketGUID)); err != nil {
+		return
+	}
+	expected = make([]byte, 28)
+	base64.StdEncoding.Encode(expected, h.Sum(nil))
+	return
+}
+
+// Client handshake described in draft-ietf-hybi-thewebsocket-protocol-17
+func hybiClientHandshake(config *Config, br *bufio.Reader, bw *bufio.Writer) (err error) {
+	bw.WriteString("GET " + config.Location.RequestURI() + " HTTP/1.1\r\n")
+
+	// According to RFC 6874, an HTTP client, proxy, or other
+	// intermediary must remove any IPv6 zone identifier attached
+	// to an outgoing URI.
+	bw.WriteString("Host: " + removeZone(config.Location.Host) + "\r\n")
+	bw.WriteString("Upgrade: websocket\r\n")
+	bw.WriteString("Connection: Upgrade\r\n")
+	nonce := generateNonce()
+	if config.handshakeData != nil {
+		nonce = []byte(config.handshakeData["key"])
+	}
+	bw.WriteString("Sec-WebSocket-Key: " + string(nonce) + "\r\n")
+	bw.WriteString("Origin: " + strings.ToLower(config.Origin.String()) + "\r\n")
+
+	if config.Version != ProtocolVersionHybi13 {
+		return ErrBadProtocolVersion
+	}
+
+	bw.WriteString("Sec-WebSocket-Version: " + fmt.Sprintf("%d", config.Version) + "\r\n")
+	if len(config.Protocol) > 0 {
+		bw.WriteString("Sec-WebSocket-Protocol: " + strings.Join(config.Protocol, ", ") + "\r\n")
+	}
+	// TODO(ukai): send Sec-WebSocket-Extensions.
+	err = config.Header.WriteSubset(bw, handshakeHeader)
+	if err != nil {
+		return err
+	}
+
+	bw.WriteString("\r\n")
+	if err = bw.Flush(); err != nil {
+		return err
+	}
+
+	resp, err := http.ReadResponse(br, &http.Request{Method: "GET"})
+	if err != nil {
+		return err
+	}
+	if resp.StatusCode != 101 {
+		return ErrBadStatus
+	}
+	if strings.ToLower(resp.Header.Get("Upgrade")) != "websocket" ||
+		strings.ToLower(resp.Header.Get("Connection")) != "upgrade" {
+		return ErrBadUpgrade
+	}
+	expectedAccept, err := getNonceAccept(nonce)
+	if err != nil {
+		return err
+	}
+	if resp.Header.Get("Sec-WebSocket-Accept") != string(expectedAccept) {
+		return ErrChallengeResponse
+	}
+	if resp.Header.Get("Sec-WebSocket-Extensions") != "" {
+		return ErrUnsupportedExtensions
+	}
+	offeredProtocol := resp.Header.Get("Sec-WebSocket-Protocol")
+	if offeredProtocol != "" {
+		protocolMatched := false
+		for i := 0; i < len(config.Protocol); i++ {
+			if config.Protocol[i] == offeredProtocol {
+				protocolMatched = true
+				break
+			}
+		}
+		if !protocolMatched {
+			return ErrBadWebSocketProtocol
+		}
+		config.Protocol = []string{offeredProtocol}
+	}
+
+	return nil
+}
+
+// newHybiClientConn creates a client WebSocket connection after handshake.
+func newHybiClientConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser) *Conn {
+	return newHybiConn(config, buf, rwc, nil)
+}
+
+// A HybiServerHandshaker performs a server handshake using hybi draft protocol.
+type hybiServerHandshaker struct {
+	*Config
+	accept []byte
+}
+
+func (c *hybiServerHandshaker) ReadHandshake(buf *bufio.Reader, req *http.Request) (code int, err error) {
+	c.Version = ProtocolVersionHybi13
+	if req.Method != "GET" {
+		return http.StatusMethodNotAllowed, ErrBadRequestMethod
+	}
+	// HTTP version can be safely ignored.
+
+	if strings.ToLower(req.Header.Get("Upgrade")) != "websocket" ||
+		!strings.Contains(strings.ToLower(req.Header.Get("Connection")), "upgrade") {
+		return http.StatusBadRequest, ErrNotWebSocket
+	}
+
+	key := req.Header.Get("Sec-Websocket-Key")
+	if key == "" {
+		return http.StatusBadRequest, ErrChallengeResponse
+	}
+	version := req.Header.Get("Sec-Websocket-Version")
+	switch version {
+	case "13":
+		c.Version = ProtocolVersionHybi13
+	default:
+		return http.StatusBadRequest, ErrBadWebSocketVersion
+	}
+	var scheme string
+	if req.TLS != nil {
+		scheme = "wss"
+	} else {
+		scheme = "ws"
+	}
+	c.Location, err = url.ParseRequestURI(scheme + "://" + req.Host + req.URL.RequestURI())
+	if err != nil {
+		return http.StatusBadRequest, err
+	}
+	protocol := strings.TrimSpace(req.Header.Get("Sec-Websocket-Protocol"))
+	if protocol != "" {
+		protocols := strings.Split(protocol, ",")
+		for i := 0; i < len(protocols); i++ {
+			c.Protocol = append(c.Protocol, strings.TrimSpace(protocols[i]))
+		}
+	}
+	c.accept, err = getNonceAccept([]byte(key))
+	if err != nil {
+		return http.StatusInternalServerError, err
+	}
+	return http.StatusSwitchingProtocols, nil
+}
+
+// Origin parses the Origin header in req.
+// If the Origin header is not set, it returns nil and nil.
+func Origin(config *Config, req *http.Request) (*url.URL, error) {
+	var origin string
+	switch config.Version {
+	case ProtocolVersionHybi13:
+		origin = req.Header.Get("Origin")
+	}
+	if origin == "" {
+		return nil, nil
+	}
+	return url.ParseRequestURI(origin)
+}
+
+func (c *hybiServerHandshaker) AcceptHandshake(buf *bufio.Writer) (err error) {
+	if len(c.Protocol) > 0 {
+		if len(c.Protocol) != 1 {
+			// You need choose a Protocol in Handshake func in Server.
+			return ErrBadWebSocketProtocol
+		}
+	}
+	buf.WriteString("HTTP/1.1 101 Switching Protocols\r\n")
+	buf.WriteString("Upgrade: websocket\r\n")
+	buf.WriteString("Connection: Upgrade\r\n")
+	buf.WriteString("Sec-WebSocket-Accept: " + string(c.accept) + "\r\n")
+	if len(c.Protocol) > 0 {
+		buf.WriteString("Sec-WebSocket-Protocol: " + c.Protocol[0] + "\r\n")
+	}
+	// TODO(ukai): send Sec-WebSocket-Extensions.
+	if c.Header != nil {
+		err := c.Header.WriteSubset(buf, handshakeHeader)
+		if err != nil {
+			return err
+		}
+	}
+	buf.WriteString("\r\n")
+	return buf.Flush()
+}
+
+func (c *hybiServerHandshaker) NewServerConn(buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
+	return newHybiServerConn(c.Config, buf, rwc, request)
+}
+
+// newHybiServerConn returns a new WebSocket connection speaking hybi draft protocol.
+func newHybiServerConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
+	return newHybiConn(config, buf, rwc, request)
+}
diff --git a/vendor/golang.org/x/net/websocket/server.go b/vendor/golang.org/x/net/websocket/server.go
new file mode 100644
index 00000000..0895dea1
--- /dev/null
+++ b/vendor/golang.org/x/net/websocket/server.go
@@ -0,0 +1,113 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"net/http"
+)
+
+func newServerConn(rwc io.ReadWriteCloser, buf *bufio.ReadWriter, req *http.Request, config *Config, handshake func(*Config, *http.Request) error) (conn *Conn, err error) {
+	var hs serverHandshaker = &hybiServerHandshaker{Config: config}
+	code, err := hs.ReadHandshake(buf.Reader, req)
+	if err == ErrBadWebSocketVersion {
+		fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
+		fmt.Fprintf(buf, "Sec-WebSocket-Version: %s\r\n", SupportedProtocolVersion)
+		buf.WriteString("\r\n")
+		buf.WriteString(err.Error())
+		buf.Flush()
+		return
+	}
+	if err != nil {
+		fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
+		buf.WriteString("\r\n")
+		buf.WriteString(err.Error())
+		buf.Flush()
+		return
+	}
+	if handshake != nil {
+		err = handshake(config, req)
+		if err != nil {
+			code = http.StatusForbidden
+			fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
+			buf.WriteString("\r\n")
+			buf.Flush()
+			return
+		}
+	}
+	err = hs.AcceptHandshake(buf.Writer)
+	if err != nil {
+		code = http.StatusBadRequest
+		fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
+		buf.WriteString("\r\n")
+		buf.Flush()
+		return
+	}
+	conn = hs.NewServerConn(buf, rwc, req)
+	return
+}
+
+// Server represents a server of a WebSocket.
+type Server struct {
+	// Config is a WebSocket configuration for new WebSocket connection.
+	Config
+
+	// Handshake is an optional function in WebSocket handshake.
+	// For example, you can check, or don't check Origin header.
+	// Another example, you can select config.Protocol.
+	Handshake func(*Config, *http.Request) error
+
+	// Handler handles a WebSocket connection.
+	Handler
+}
+
+// ServeHTTP implements the http.Handler interface for a WebSocket
+func (s Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	s.serveWebSocket(w, req)
+}
+
+func (s Server) serveWebSocket(w http.ResponseWriter, req *http.Request) {
+	rwc, buf, err := w.(http.Hijacker).Hijack()
+	if err != nil {
+		panic("Hijack failed: " + err.Error())
+	}
+	// The server should abort the WebSocket connection if it finds
+	// the client did not send a handshake that matches with protocol
+	// specification.
+	defer rwc.Close()
+	conn, err := newServerConn(rwc, buf, req, &s.Config, s.Handshake)
+	if err != nil {
+		return
+	}
+	if conn == nil {
+		panic("unexpected nil conn")
+	}
+	s.Handler(conn)
+}
+
+// Handler is a simple interface to a WebSocket browser client.
+// It checks if Origin header is valid URL by default.
+// You might want to verify websocket.Conn.Config().Origin in the func.
+// If you use Server instead of Handler, you could call websocket.Origin and
+// check the origin in your Handshake func. So, if you want to accept
+// non-browser clients, which do not send an Origin header, set a
+// Server.Handshake that does not check the origin.
+type Handler func(*Conn)
+
+func checkOrigin(config *Config, req *http.Request) (err error) {
+	config.Origin, err = Origin(config, req)
+	if err == nil && config.Origin == nil {
+		return fmt.Errorf("null origin")
+	}
+	return err
+}
+
+// ServeHTTP implements the http.Handler interface for a WebSocket
+func (h Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	s := Server{Handler: h, Handshake: checkOrigin}
+	s.serveWebSocket(w, req)
+}
diff --git a/vendor/golang.org/x/net/websocket/websocket.go b/vendor/golang.org/x/net/websocket/websocket.go
new file mode 100644
index 00000000..9412191d
--- /dev/null
+++ b/vendor/golang.org/x/net/websocket/websocket.go
@@ -0,0 +1,411 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package websocket implements a client and server for the WebSocket protocol
+// as specified in RFC 6455.
+package websocket // import "golang.org/x/net/websocket"
+
+import (
+	"bufio"
+	"crypto/tls"
+	"encoding/json"
+	"errors"
+	"io"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"sync"
+	"time"
+)
+
+const (
+	ProtocolVersionHybi13    = 13
+	ProtocolVersionHybi      = ProtocolVersionHybi13
+	SupportedProtocolVersion = "13"
+
+	ContinuationFrame = 0
+	TextFrame         = 1
+	BinaryFrame       = 2
+	CloseFrame        = 8
+	PingFrame         = 9
+	PongFrame         = 10
+	UnknownFrame      = 255
+)
+
+// ProtocolError represents WebSocket protocol errors.
+type ProtocolError struct {
+	ErrorString string
+}
+
+func (err *ProtocolError) Error() string { return err.ErrorString }
+
+var (
+	ErrBadProtocolVersion   = &ProtocolError{"bad protocol version"}
+	ErrBadScheme            = &ProtocolError{"bad scheme"}
+	ErrBadStatus            = &ProtocolError{"bad status"}
+	ErrBadUpgrade           = &ProtocolError{"missing or bad upgrade"}
+	ErrBadWebSocketOrigin   = &ProtocolError{"missing or bad WebSocket-Origin"}
+	ErrBadWebSocketLocation = &ProtocolError{"missing or bad WebSocket-Location"}
+	ErrBadWebSocketProtocol = &ProtocolError{"missing or bad WebSocket-Protocol"}
+	ErrBadWebSocketVersion  = &ProtocolError{"missing or bad WebSocket Version"}
+	ErrChallengeResponse    = &ProtocolError{"mismatch challenge/response"}
+	ErrBadFrame             = &ProtocolError{"bad frame"}
+	ErrBadFrameBoundary     = &ProtocolError{"not on frame boundary"}
+	ErrNotWebSocket         = &ProtocolError{"not websocket protocol"}
+	ErrBadRequestMethod     = &ProtocolError{"bad method"}
+	ErrNotSupported         = &ProtocolError{"not supported"}
+)
+
+// Addr is an implementation of net.Addr for WebSocket.
+type Addr struct {
+	*url.URL
+}
+
+// Network returns the network type for a WebSocket, "websocket".
+func (addr *Addr) Network() string { return "websocket" }
+
+// Config is a WebSocket configuration
+type Config struct {
+	// A WebSocket server address.
+	Location *url.URL
+
+	// A Websocket client origin.
+	Origin *url.URL
+
+	// WebSocket subprotocols.
+	Protocol []string
+
+	// WebSocket protocol version.
+	Version int
+
+	// TLS config for secure WebSocket (wss).
+	TlsConfig *tls.Config
+
+	// Additional header fields to be sent in WebSocket opening handshake.
+	Header http.Header
+
+	handshakeData map[string]string
+}
+
+// serverHandshaker is an interface to handle WebSocket server side handshake.
+type serverHandshaker interface {
+	// ReadHandshake reads handshake request message from client.
+	// Returns http response code and error if any.
+	ReadHandshake(buf *bufio.Reader, req *http.Request) (code int, err error)
+
+	// AcceptHandshake accepts the client handshake request and sends
+	// handshake response back to client.
+	AcceptHandshake(buf *bufio.Writer) (err error)
+
+	// NewServerConn creates a new WebSocket connection.
+	NewServerConn(buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) (conn *Conn)
+}
+
+// frameReader is an interface to read a WebSocket frame.
+type frameReader interface {
+	// Reader is to read payload of the frame.
+	io.Reader
+
+	// PayloadType returns payload type.
+	PayloadType() byte
+
+	// HeaderReader returns a reader to read header of the frame.
+	HeaderReader() io.Reader
+
+	// TrailerReader returns a reader to read trailer of the frame.
+	// If it returns nil, there is no trailer in the frame.
+	TrailerReader() io.Reader
+
+	// Len returns total length of the frame, including header and trailer.
+	Len() int
+}
+
+// frameReaderFactory is an interface to creates new frame reader.
+type frameReaderFactory interface {
+	NewFrameReader() (r frameReader, err error)
+}
+
+// frameWriter is an interface to write a WebSocket frame.
+type frameWriter interface {
+	// Writer is to write payload of the frame.
+	io.WriteCloser
+}
+
+// frameWriterFactory is an interface to create new frame writer.
+type frameWriterFactory interface {
+	NewFrameWriter(payloadType byte) (w frameWriter, err error)
+}
+
+type frameHandler interface {
+	HandleFrame(frame frameReader) (r frameReader, err error)
+	WriteClose(status int) (err error)
+}
+
+// Conn represents a WebSocket connection.
+//
+// Multiple goroutines may invoke methods on a Conn simultaneously.
+type Conn struct {
+	config  *Config
+	request *http.Request
+
+	buf *bufio.ReadWriter
+	rwc io.ReadWriteCloser
+
+	rio sync.Mutex
+	frameReaderFactory
+	frameReader
+
+	wio sync.Mutex
+	frameWriterFactory
+
+	frameHandler
+	PayloadType        byte
+	defaultCloseStatus int
+}
+
+// Read implements the io.Reader interface:
+// it reads data of a frame from the WebSocket connection.
+// if msg is not large enough for the frame data, it fills the msg and next Read
+// will read the rest of the frame data.
+// it reads Text frame or Binary frame.
+func (ws *Conn) Read(msg []byte) (n int, err error) {
+	ws.rio.Lock()
+	defer ws.rio.Unlock()
+again:
+	if ws.frameReader == nil {
+		frame, err := ws.frameReaderFactory.NewFrameReader()
+		if err != nil {
+			return 0, err
+		}
+		ws.frameReader, err = ws.frameHandler.HandleFrame(frame)
+		if err != nil {
+			return 0, err
+		}
+		if ws.frameReader == nil {
+			goto again
+		}
+	}
+	n, err = ws.frameReader.Read(msg)
+	if err == io.EOF {
+		if trailer := ws.frameReader.TrailerReader(); trailer != nil {
+			io.Copy(ioutil.Discard, trailer)
+		}
+		ws.frameReader = nil
+		goto again
+	}
+	return n, err
+}
+
+// Write implements the io.Writer interface:
+// it writes data as a frame to the WebSocket connection.
+func (ws *Conn) Write(msg []byte) (n int, err error) {
+	ws.wio.Lock()
+	defer ws.wio.Unlock()
+	w, err := ws.frameWriterFactory.NewFrameWriter(ws.PayloadType)
+	if err != nil {
+		return 0, err
+	}
+	n, err = w.Write(msg)
+	w.Close()
+	return n, err
+}
+
+// Close implements the io.Closer interface.
+func (ws *Conn) Close() error {
+	err := ws.frameHandler.WriteClose(ws.defaultCloseStatus)
+	err1 := ws.rwc.Close()
+	if err != nil {
+		return err
+	}
+	return err1
+}
+
+func (ws *Conn) IsClientConn() bool { return ws.request == nil }
+func (ws *Conn) IsServerConn() bool { return ws.request != nil }
+
+// LocalAddr returns the WebSocket Origin for the connection for client, or
+// the WebSocket location for server.
+func (ws *Conn) LocalAddr() net.Addr {
+	if ws.IsClientConn() {
+		return &Addr{ws.config.Origin}
+	}
+	return &Addr{ws.config.Location}
+}
+
+// RemoteAddr returns the WebSocket location for the connection for client, or
+// the Websocket Origin for server.
+func (ws *Conn) RemoteAddr() net.Addr {
+	if ws.IsClientConn() {
+		return &Addr{ws.config.Location}
+	}
+	return &Addr{ws.config.Origin}
+}
+
+var errSetDeadline = errors.New("websocket: cannot set deadline: not using a net.Conn")
+
+// SetDeadline sets the connection's network read & write deadlines.
+func (ws *Conn) SetDeadline(t time.Time) error {
+	if conn, ok := ws.rwc.(net.Conn); ok {
+		return conn.SetDeadline(t)
+	}
+	return errSetDeadline
+}
+
+// SetReadDeadline sets the connection's network read deadline.
+func (ws *Conn) SetReadDeadline(t time.Time) error {
+	if conn, ok := ws.rwc.(net.Conn); ok {
+		return conn.SetReadDeadline(t)
+	}
+	return errSetDeadline
+}
+
+// SetWriteDeadline sets the connection's network write deadline.
+func (ws *Conn) SetWriteDeadline(t time.Time) error {
+	if conn, ok := ws.rwc.(net.Conn); ok {
+		return conn.SetWriteDeadline(t)
+	}
+	return errSetDeadline
+}
+
+// Config returns the WebSocket config.
+func (ws *Conn) Config() *Config { return ws.config }
+
+// Request returns the http request upgraded to the WebSocket.
+// It is nil for client side.
+func (ws *Conn) Request() *http.Request { return ws.request }
+
+// Codec represents a symmetric pair of functions that implement a codec.
+type Codec struct {
+	Marshal   func(v interface{}) (data []byte, payloadType byte, err error)
+	Unmarshal func(data []byte, payloadType byte, v interface{}) (err error)
+}
+
+// Send sends v marshaled by cd.Marshal as single frame to ws.
+func (cd Codec) Send(ws *Conn, v interface{}) (err error) {
+	data, payloadType, err := cd.Marshal(v)
+	if err != nil {
+		return err
+	}
+	ws.wio.Lock()
+	defer ws.wio.Unlock()
+	w, err := ws.frameWriterFactory.NewFrameWriter(payloadType)
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(data)
+	w.Close()
+	return err
+}
+
+// Receive receives single frame from ws, unmarshaled by cd.Unmarshal and stores in v.
+func (cd Codec) Receive(ws *Conn, v interface{}) (err error) {
+	ws.rio.Lock()
+	defer ws.rio.Unlock()
+	if ws.frameReader != nil {
+		_, err = io.Copy(ioutil.Discard, ws.frameReader)
+		if err != nil {
+			return err
+		}
+		ws.frameReader = nil
+	}
+again:
+	frame, err := ws.frameReaderFactory.NewFrameReader()
+	if err != nil {
+		return err
+	}
+	frame, err = ws.frameHandler.HandleFrame(frame)
+	if err != nil {
+		return err
+	}
+	if frame == nil {
+		goto again
+	}
+	payloadType := frame.PayloadType()
+	data, err := ioutil.ReadAll(frame)
+	if err != nil {
+		return err
+	}
+	return cd.Unmarshal(data, payloadType, v)
+}
+
+func marshal(v interface{}) (msg []byte, payloadType byte, err error) {
+	switch data := v.(type) {
+	case string:
+		return []byte(data), TextFrame, nil
+	case []byte:
+		return data, BinaryFrame, nil
+	}
+	return nil, UnknownFrame, ErrNotSupported
+}
+
+func unmarshal(msg []byte, payloadType byte, v interface{}) (err error) {
+	switch data := v.(type) {
+	case *string:
+		*data = string(msg)
+		return nil
+	case *[]byte:
+		*data = msg
+		return nil
+	}
+	return ErrNotSupported
+}
+
+/*
+Message is a codec to send/receive text/binary data in a frame on WebSocket connection.
+To send/receive text frame, use string type.
+To send/receive binary frame, use []byte type.
+
+Trivial usage:
+
+	import "websocket"
+
+	// receive text frame
+	var message string
+	websocket.Message.Receive(ws, &message)
+
+	// send text frame
+	message = "hello"
+	websocket.Message.Send(ws, message)
+
+	// receive binary frame
+	var data []byte
+	websocket.Message.Receive(ws, &data)
+
+	// send binary frame
+	data = []byte{0, 1, 2}
+	websocket.Message.Send(ws, data)
+
+*/
+var Message = Codec{marshal, unmarshal}
+
+func jsonMarshal(v interface{}) (msg []byte, payloadType byte, err error) {
+	msg, err = json.Marshal(v)
+	return msg, TextFrame, err
+}
+
+func jsonUnmarshal(msg []byte, payloadType byte, v interface{}) (err error) {
+	return json.Unmarshal(msg, v)
+}
+
+/*
+JSON is a codec to send/receive JSON data in a frame from a WebSocket connection.
+
+Trivial usage:
+
+	import "websocket"
+
+	type T struct {
+		Msg string
+		Count int
+	}
+
+	// receive JSON type T
+	var data T
+	websocket.JSON.Receive(ws, &data)
+
+	// send JSON type T
+	websocket.JSON.Send(ws, data)
+*/
+var JSON = Codec{jsonMarshal, jsonUnmarshal}
diff --git a/vendor/manifest b/vendor/manifest
index dc2f9253..c07f6e1b 100644
--- a/vendor/manifest
+++ b/vendor/manifest
@@ -111,6 +111,14 @@
 			"notests": true
 		},
 		{
+			"importpath": "github.com/nlopes/slack",
+			"repository": "https://github.com/nlopes/slack",
+			"vcs": "git",
+			"revision": "4feee83bb2b31d790977ce727a028c6a542c72c7",
+			"branch": "HEAD",
+			"notests": true
+		},
+		{
 			"importpath": "github.com/pborman/uuid",
 			"repository": "https://github.com/pborman/uuid",
 			"vcs": "",
@@ -187,6 +195,15 @@
 			"notests": true
 		},
 		{
+			"importpath": "golang.org/x/net/websocket",
+			"repository": "https://go.googlesource.com/net",
+			"vcs": "git",
+			"revision": "1358eff22f0dd0c54fc521042cc607f6ff4b531a",
+			"branch": "master",
+			"path": "/websocket",
+			"notests": true
+		},
+		{
 			"importpath": "gopkg.in/gcfg.v1",
 			"repository": "https://gopkg.in/gcfg.v1",
 			"vcs": "",