Update vendor (nlopes/slack)

27 files changed, 1404 insertions, 312 deletions

diff --git a/vendor/github.com/nlopes/slack/admin.go b/vendor/github.com/nlopes/slack/admin.go
index 393b2880..478c4f40 100644
--- a/vendor/github.com/nlopes/slack/admin.go
+++ b/vendor/github.com/nlopes/slack/admin.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net/url"
@@ -11,9 +12,9 @@ type adminResponse struct {
 	Error string `json:"error"`
 }
 
-func adminRequest(method string, teamName string, values url.Values, debug bool) (*adminResponse, error) {
+func adminRequest(ctx context.Context, method string, teamName string, values url.Values, debug bool) (*adminResponse, error) {
 	adminResponse := &adminResponse{}
-	err := parseAdminResponse(method, teamName, values, adminResponse, debug)
+	err := parseAdminResponse(ctx, method, teamName, values, adminResponse, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -27,6 +28,11 @@ func adminRequest(method string, teamName string, values url.Values, debug bool)
 
 // DisableUser disabled a user account, given a user ID
 func (api *Client) DisableUser(teamName string, uid string) error {
+	return api.DisableUserContext(context.Background(), teamName, uid)
+}
+
+// DisableUserContext disabled a user account, given a user ID with a custom context
+func (api *Client) DisableUserContext(ctx context.Context, teamName string, uid string) error {
 	values := url.Values{
 		"user":       {uid},
 		"token":      {api.config.token},
@@ -34,7 +40,7 @@ func (api *Client) DisableUser(teamName string, uid string) error {
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("setInactive", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "setInactive", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to disable user with id '%s': %s", uid, err)
 	}
@@ -43,13 +49,12 @@ func (api *Client) DisableUser(teamName string, uid string) error {
 }
 
 // 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 {
+func (api *Client) InviteGuest(teamName, channel, firstName, lastName, emailAddress string) error {
+	return api.InviteGuestContext(context.Background(), teamName, channel, firstName, lastName, emailAddress)
+}
+
+// InviteGuestContext invites a user to Slack as a single-channel guest with a custom context
+func (api *Client) InviteGuestContext(ctx context.Context, teamName, channel, firstName, lastName, emailAddress string) error {
 	values := url.Values{
 		"email":            {emailAddress},
 		"channels":         {channel},
@@ -61,7 +66,7 @@ func (api *Client) InviteGuest(
 		"_attempts":        {"1"},
 	}
 
-	_, err := adminRequest("invite", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "invite", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to invite single-channel guest: %s", err)
 	}
@@ -70,13 +75,12 @@ func (api *Client) InviteGuest(
 }
 
 // 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 {
+func (api *Client) InviteRestricted(teamName, channel, firstName, lastName, emailAddress string) error {
+	return api.InviteRestrictedContext(context.Background(), teamName, channel, firstName, lastName, emailAddress)
+}
+
+// InviteRestrictedContext invites a user to Slack as a restricted account with a custom context
+func (api *Client) InviteRestrictedContext(ctx context.Context, teamName, channel, firstName, lastName, emailAddress string) error {
 	values := url.Values{
 		"email":      {emailAddress},
 		"channels":   {channel},
@@ -88,7 +92,7 @@ func (api *Client) InviteRestricted(
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("invite", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "invite", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to restricted account: %s", err)
 	}
@@ -97,12 +101,12 @@ func (api *Client) InviteRestricted(
 }
 
 // InviteToTeam invites a user to a Slack team
-func (api *Client) InviteToTeam(
-	teamName string,
-	firstName string,
-	lastName string,
-	emailAddress string,
-) error {
+func (api *Client) InviteToTeam(teamName, firstName, lastName, emailAddress string) error {
+	return api.InviteToTeamContext(context.Background(), teamName, firstName, lastName, emailAddress)
+}
+
+// InviteToTeamContext invites a user to a Slack team with a custom context
+func (api *Client) InviteToTeamContext(ctx context.Context, teamName, firstName, lastName, emailAddress string) error {
 	values := url.Values{
 		"email":      {emailAddress},
 		"first_name": {firstName},
@@ -112,7 +116,7 @@ func (api *Client) InviteToTeam(
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("invite", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "invite", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to invite to team: %s", err)
 	}
@@ -121,7 +125,12 @@ func (api *Client) InviteToTeam(
 }
 
 // SetRegular enables the specified user
-func (api *Client) SetRegular(teamName string, user string) error {
+func (api *Client) SetRegular(teamName, user string) error {
+	return api.SetRegularContext(context.Background(), teamName, user)
+}
+
+// SetRegularContext enables the specified user with a custom context
+func (api *Client) SetRegularContext(ctx context.Context, teamName, user string) error {
 	values := url.Values{
 		"user":       {user},
 		"token":      {api.config.token},
@@ -129,7 +138,7 @@ func (api *Client) SetRegular(teamName string, user string) error {
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("setRegular", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "setRegular", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to change the user (%s) to a regular user: %s", user, err)
 	}
@@ -138,7 +147,12 @@ func (api *Client) SetRegular(teamName string, user string) error {
 }
 
 // SendSSOBindingEmail sends an SSO binding email to the specified user
-func (api *Client) SendSSOBindingEmail(teamName string, user string) error {
+func (api *Client) SendSSOBindingEmail(teamName, user string) error {
+	return api.SendSSOBindingEmailContext(context.Background(), teamName, user)
+}
+
+// SendSSOBindingEmailContext sends an SSO binding email to the specified user with a custom context
+func (api *Client) SendSSOBindingEmailContext(ctx context.Context, teamName, user string) error {
 	values := url.Values{
 		"user":       {user},
 		"token":      {api.config.token},
@@ -146,7 +160,7 @@ func (api *Client) SendSSOBindingEmail(teamName string, user string) error {
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("sendSSOBind", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "sendSSOBind", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to send SSO binding email for user (%s): %s", user, err)
 	}
@@ -156,6 +170,11 @@ func (api *Client) SendSSOBindingEmail(teamName string, user string) error {
 
 // SetUltraRestricted converts a user into a single-channel guest
 func (api *Client) SetUltraRestricted(teamName, uid, channel string) error {
+	return api.SetUltraRestrictedContext(context.Background(), teamName, uid, channel)
+}
+
+// SetUltraRestrictedContext converts a user into a single-channel guest with a custom context
+func (api *Client) SetUltraRestrictedContext(ctx context.Context, teamName, uid, channel string) error {
 	values := url.Values{
 		"user":       {uid},
 		"channel":    {channel},
@@ -164,7 +183,7 @@ func (api *Client) SetUltraRestricted(teamName, uid, channel string) error {
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("setUltraRestricted", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "setUltraRestricted", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to ultra-restrict account: %s", err)
 	}
@@ -174,6 +193,11 @@ func (api *Client) SetUltraRestricted(teamName, uid, channel string) error {
 
 // SetRestricted converts a user into a restricted account
 func (api *Client) SetRestricted(teamName, uid string) error {
+	return api.SetRestrictedContext(context.Background(), teamName, uid)
+}
+
+// SetRestrictedContext converts a user into a restricted account with a custom context
+func (api *Client) SetRestrictedContext(ctx context.Context, teamName, uid string) error {
 	values := url.Values{
 		"user":       {uid},
 		"token":      {api.config.token},
@@ -181,7 +205,7 @@ func (api *Client) SetRestricted(teamName, uid string) error {
 		"_attempts":  {"1"},
 	}
 
-	_, err := adminRequest("setRestricted", teamName, values, api.debug)
+	_, err := adminRequest(ctx, "setRestricted", teamName, values, api.debug)
 	if err != nil {
 		return fmt.Errorf("Failed to restrict account: %s", err)
 	}
diff --git a/vendor/github.com/nlopes/slack/attachments.go b/vendor/github.com/nlopes/slack/attachments.go
index f7b81617..c5a66d96 100644
--- a/vendor/github.com/nlopes/slack/attachments.go
+++ b/vendor/github.com/nlopes/slack/attachments.go
@@ -10,16 +10,34 @@ type AttachmentField struct {
 	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
+// AttachmentAction is a button or menu to be included in the attachment. Required when
+// using message buttons or menus 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.
+	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" or "select".
+	Value           string                        `json:"value,omitempty"`            // Optional.
+	DataSource      string                        `json:"data_source,omitempty"`      // Optional.
+	MinQueryLength  int                           `json:"min_query_length,omitempty"` // Optional. Default value is 1.
+	Options         []AttachmentActionOption      `json:"options,omitempty"`          // Optional. Maximum of 100 options can be provided in each menu.
+	SelectedOptions []AttachmentActionOption      `json:"selected_options,omitempty"` // Optional. The first element of this array will be set as the pre-selected option for this menu.
+	OptionGroups    []AttachmentActionOptionGroup `json:"option_groups,omitempty"`    // Optional.
+	Confirm         *ConfirmationField            `json:"confirm,omitempty"`          // Optional.
+}
+
+// AttachmentActionOption the individual option to appear in action menu.
+type AttachmentActionOption struct {
+	Text        string `json:"text"`                  // Required.
+	Value       string `json:"value"`                 // Required.
+	Description string `json:"description,omitempty"` // Optional. Up to 30 characters.
+}
+
+// AttachmentActionOptionGroup is a semi-hierarchal way to list available options to appear in action menu.
+type AttachmentActionOptionGroup struct {
+	Text    string                   `json:"text"`    // Required.
+	Options []AttachmentActionOption `json:"options"` // Required.
 }
 
 // AttachmentActionCallback is sent from Slack when a user clicks a button in an interactive message (aka AttachmentAction)
diff --git a/vendor/github.com/nlopes/slack/bots.go b/vendor/github.com/nlopes/slack/bots.go
index 555915e4..13a78cb1 100644
--- a/vendor/github.com/nlopes/slack/bots.go
+++ b/vendor/github.com/nlopes/slack/bots.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 )
@@ -18,9 +19,9 @@ type botResponseFull struct {
 	SlackResponse
 }
 
-func botRequest(path string, values url.Values, debug bool) (*botResponseFull, error) {
+func botRequest(ctx context.Context, path string, values url.Values, debug bool) (*botResponseFull, error) {
 	response := &botResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -32,11 +33,16 @@ func botRequest(path string, values url.Values, debug bool) (*botResponseFull, e
 
 // GetBotInfo will retrieve the complete bot information
 func (api *Client) GetBotInfo(bot string) (*Bot, error) {
+	return api.GetBotInfoContext(context.Background(), bot)
+}
+
+// GetBotInfoContext will retrieve the complete bot information using a custom context
+func (api *Client) GetBotInfoContext(ctx context.Context, bot string) (*Bot, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"bot":   {bot},
 	}
-	response, err := botRequest("bots.info", values, api.debug)
+	response, err := botRequest(ctx, "bots.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/channels.go b/vendor/github.com/nlopes/slack/channels.go
index 05cfbe1d..4a67b2fb 100644
--- a/vendor/github.com/nlopes/slack/channels.go
+++ b/vendor/github.com/nlopes/slack/channels.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -24,9 +25,9 @@ type Channel struct {
 	IsMember  bool `json:"is_member"`
 }
 
-func channelRequest(path string, values url.Values, debug bool) (*channelResponseFull, error) {
+func channelRequest(ctx context.Context, path string, values url.Values, debug bool) (*channelResponseFull, error) {
 	response := &channelResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -38,11 +39,16 @@ func channelRequest(path string, values url.Values, debug bool) (*channelRespons
 
 // ArchiveChannel archives the given channel
 func (api *Client) ArchiveChannel(channel string) error {
+	return api.ArchiveChannelContext(context.Background(), channel)
+}
+
+// ArchiveChannelContext archives the given channel with a custom context
+func (api *Client) ArchiveChannelContext(ctx context.Context, channel string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 	}
-	_, err := channelRequest("channels.archive", values, api.debug)
+	_, err := channelRequest(ctx, "channels.archive", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -51,11 +57,16 @@ func (api *Client) ArchiveChannel(channel string) error {
 
 // UnarchiveChannel unarchives the given channel
 func (api *Client) UnarchiveChannel(channel string) error {
+	return api.UnarchiveChannelContext(context.Background(), channel)
+}
+
+// UnarchiveChannelContext unarchives the given channel with a custom context
+func (api *Client) UnarchiveChannelContext(ctx context.Context, channel string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 	}
-	_, err := channelRequest("channels.unarchive", values, api.debug)
+	_, err := channelRequest(ctx, "channels.unarchive", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -64,11 +75,16 @@ func (api *Client) UnarchiveChannel(channel string) error {
 
 // CreateChannel creates a channel with the given name and returns a *Channel
 func (api *Client) CreateChannel(channel string) (*Channel, error) {
+	return api.CreateChannelContext(context.Background(), channel)
+}
+
+// CreateChannelContext creates a channel with the given name and returns a *Channel with a custom context
+func (api *Client) CreateChannelContext(ctx context.Context, channel string) (*Channel, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"name":  {channel},
 	}
-	response, err := channelRequest("channels.create", values, api.debug)
+	response, err := channelRequest(ctx, "channels.create", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -77,6 +93,11 @@ func (api *Client) CreateChannel(channel string) (*Channel, error) {
 
 // GetChannelHistory retrieves the channel history
 func (api *Client) GetChannelHistory(channel string, params HistoryParameters) (*History, error) {
+	return api.GetChannelHistoryContext(context.Background(), channel, params)
+}
+
+// GetChannelHistoryContext retrieves the channel history with a custom context
+func (api *Client) GetChannelHistoryContext(ctx context.Context, channel string, params HistoryParameters) (*History, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
@@ -104,7 +125,7 @@ func (api *Client) GetChannelHistory(channel string, params HistoryParameters) (
 			values.Add("unreads", "0")
 		}
 	}
-	response, err := channelRequest("channels.history", values, api.debug)
+	response, err := channelRequest(ctx, "channels.history", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -113,11 +134,16 @@ func (api *Client) GetChannelHistory(channel string, params HistoryParameters) (
 
 // GetChannelInfo retrieves the given channel
 func (api *Client) GetChannelInfo(channel string) (*Channel, error) {
+	return api.GetChannelInfoContext(context.Background(), channel)
+}
+
+// GetChannelInfoContext retrieves the given channel with a custom context
+func (api *Client) GetChannelInfoContext(ctx context.Context, channel string) (*Channel, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 	}
-	response, err := channelRequest("channels.info", values, api.debug)
+	response, err := channelRequest(ctx, "channels.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -126,12 +152,17 @@ func (api *Client) GetChannelInfo(channel string) (*Channel, error) {
 
 // InviteUserToChannel invites a user to a given channel and returns a *Channel
 func (api *Client) InviteUserToChannel(channel, user string) (*Channel, error) {
+	return api.InviteUserToChannelContext(context.Background(), channel, user)
+}
+
+// InviteUserToChannelCustom invites a user to a given channel and returns a *Channel with a custom context
+func (api *Client) InviteUserToChannelContext(ctx context.Context, channel, user string) (*Channel, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"user":    {user},
 	}
-	response, err := channelRequest("channels.invite", values, api.debug)
+	response, err := channelRequest(ctx, "channels.invite", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -140,11 +171,16 @@ func (api *Client) InviteUserToChannel(channel, user string) (*Channel, error) {
 
 // JoinChannel joins the currently authenticated user to a channel
 func (api *Client) JoinChannel(channel string) (*Channel, error) {
+	return api.JoinChannelContext(context.Background(), channel)
+}
+
+// JoinChannelContext joins the currently authenticated user to a channel with a custom context
+func (api *Client) JoinChannelContext(ctx context.Context, channel string) (*Channel, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"name":  {channel},
 	}
-	response, err := channelRequest("channels.join", values, api.debug)
+	response, err := channelRequest(ctx, "channels.join", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -153,11 +189,16 @@ func (api *Client) JoinChannel(channel string) (*Channel, error) {
 
 // LeaveChannel makes the authenticated user leave the given channel
 func (api *Client) LeaveChannel(channel string) (bool, error) {
+	return api.LeaveChannelContext(context.Background(), channel)
+}
+
+// LeaveChannelContext makes the authenticated user leave the given channel with a custom context
+func (api *Client) LeaveChannelContext(ctx context.Context, channel string) (bool, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 	}
-	response, err := channelRequest("channels.leave", values, api.debug)
+	response, err := channelRequest(ctx, "channels.leave", values, api.debug)
 	if err != nil {
 		return false, err
 	}
@@ -169,12 +210,17 @@ func (api *Client) LeaveChannel(channel string) (bool, error) {
 
 // KickUserFromChannel kicks a user from a given channel
 func (api *Client) KickUserFromChannel(channel, user string) error {
+	return api.KickUserFromChannelContext(context.Background(), channel, user)
+}
+
+// KickUserFromChannelContext kicks a user from a given channel with a custom context
+func (api *Client) KickUserFromChannelContext(ctx context.Context, channel, user string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"user":    {user},
 	}
-	_, err := channelRequest("channels.kick", values, api.debug)
+	_, err := channelRequest(ctx, "channels.kick", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -183,13 +229,18 @@ func (api *Client) KickUserFromChannel(channel, user string) error {
 
 // GetChannels retrieves all the channels
 func (api *Client) GetChannels(excludeArchived bool) ([]Channel, error) {
+	return api.GetChannelsContext(context.Background(), excludeArchived)
+}
+
+// GetChannelsContext retrieves all the channels with a custom context
+func (api *Client) GetChannelsContext(ctx context.Context, 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)
+	response, err := channelRequest(ctx, "channels.list", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -202,12 +253,18 @@ func (api *Client) GetChannels(excludeArchived bool) ([]Channel, error) {
 // (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 {
+	return api.SetChannelReadMarkContext(context.Background(), channel, ts)
+}
+
+// SetChannelReadMarkContext sets the read mark of a given channel to a specific point with a custom context
+// For more details see SetChannelReadMark documentation
+func (api *Client) SetChannelReadMarkContext(ctx context.Context, channel, ts string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"ts":      {ts},
 	}
-	_, err := channelRequest("channels.mark", values, api.debug)
+	_, err := channelRequest(ctx, "channels.mark", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -216,6 +273,11 @@ func (api *Client) SetChannelReadMark(channel, ts string) error {
 
 // RenameChannel renames a given channel
 func (api *Client) RenameChannel(channel, name string) (*Channel, error) {
+	return api.RenameChannelContext(context.Background(), channel, name)
+}
+
+// RenameChannelContext renames a given channel with a custom context
+func (api *Client) RenameChannelContext(ctx context.Context, channel, name string) (*Channel, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
@@ -223,23 +285,26 @@ func (api *Client) RenameChannel(channel, name string) (*Channel, error) {
 	}
 	// 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)
+	response, err := channelRequest(ctx, "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
+// SetChannelPurpose sets the channel purpose and returns the purpose that was successfully set
 func (api *Client) SetChannelPurpose(channel, purpose string) (string, error) {
+	return api.SetChannelPurposeContext(context.Background(), channel, purpose)
+}
+
+// SetChannelPurposeContext sets the channel purpose and returns the purpose that was successfully set with a custom context
+func (api *Client) SetChannelPurposeContext(ctx context.Context, channel, purpose string) (string, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"purpose": {purpose},
 	}
-	response, err := channelRequest("channels.setPurpose", values, api.debug)
+	response, err := channelRequest(ctx, "channels.setPurpose", values, api.debug)
 	if err != nil {
 		return "", err
 	}
@@ -248,14 +313,38 @@ func (api *Client) SetChannelPurpose(channel, purpose string) (string, error) {
 
 // SetChannelTopic sets the channel topic and returns the topic that was successfully set
 func (api *Client) SetChannelTopic(channel, topic string) (string, error) {
+	return api.SetChannelTopicContext(context.Background(), channel, topic)
+}
+
+// SetChannelTopicContext sets the channel topic and returns the topic that was successfully set with a custom context
+func (api *Client) SetChannelTopicContext(ctx context.Context, channel, topic string) (string, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"topic":   {topic},
 	}
-	response, err := channelRequest("channels.setTopic", values, api.debug)
+	response, err := channelRequest(ctx, "channels.setTopic", values, api.debug)
 	if err != nil {
 		return "", err
 	}
 	return response.Topic, nil
 }
+
+// GetChannelReplies gets an entire thread (a message plus all the messages in reply to it).
+func (api *Client) GetChannelReplies(channel, thread_ts string) ([]Message, error) {
+	return api.GetChannelRepliesContext(context.Background(), channel, thread_ts)
+}
+
+// GetChannelRepliesContext gets an entire thread (a message plus all the messages in reply to it) with a custom context
+func (api *Client) GetChannelRepliesContext(ctx context.Context, channel, thread_ts string) ([]Message, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"channel":   {channel},
+		"thread_ts": {thread_ts},
+	}
+	response, err := channelRequest(ctx, "channels.replies", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.History.Messages, nil
+}
diff --git a/vendor/github.com/nlopes/slack/chat.go b/vendor/github.com/nlopes/slack/chat.go
index fc909a86..9a2c4453 100644
--- a/vendor/github.com/nlopes/slack/chat.go
+++ b/vendor/github.com/nlopes/slack/chat.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"net/url"
@@ -62,30 +63,92 @@ func NewPostMessageParameters() PostMessageParameters {
 	}
 }
 
-func chatRequest(path string, values url.Values, debug bool) (*chatResponseFull, error) {
-	response := &chatResponseFull{}
-	err := post(path, values, response, debug)
+// DeleteMessage deletes a message in a channel
+func (api *Client) DeleteMessage(channel, messageTimestamp string) (string, string, error) {
+	respChannel, respTimestamp, _, err := api.SendMessageContext(context.Background(), channel, MsgOptionDelete(messageTimestamp))
+	return respChannel, respTimestamp, err
+}
+
+// DeleteMessageContext deletes a message in a channel with a custom context
+func (api *Client) DeleteMessageContext(ctx context.Context, channel, messageTimestamp string) (string, string, error) {
+	respChannel, respTimestamp, _, err := api.SendMessageContext(ctx, channel, MsgOptionDelete(messageTimestamp))
+	return respChannel, respTimestamp, err
+}
+
+// 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) {
+	respChannel, respTimestamp, _, err := api.SendMessageContext(
+		context.Background(),
+		channel,
+		MsgOptionText(text, params.EscapeText),
+		MsgOptionAttachments(params.Attachments...),
+		MsgOptionPostMessageParameters(params),
+	)
+	return respChannel, respTimestamp, err
+}
+
+// PostMessageContext sends a message to a channel with a custom context
+// For more details, see PostMessage documentation
+func (api *Client) PostMessageContext(ctx context.Context, channel, text string, params PostMessageParameters) (string, string, error) {
+	respChannel, respTimestamp, _, err := api.SendMessageContext(
+		ctx,
+		channel,
+		MsgOptionText(text, params.EscapeText),
+		MsgOptionAttachments(params.Attachments...),
+		MsgOptionPostMessageParameters(params),
+	)
+	return respChannel, respTimestamp, err
+}
+
+// UpdateMessage updates a message in a channel
+func (api *Client) UpdateMessage(channel, timestamp, text string) (string, string, string, error) {
+	return api.UpdateMessageContext(context.Background(), channel, timestamp, text)
+}
+
+// UpdateMessage updates a message in a channel
+func (api *Client) UpdateMessageContext(ctx context.Context, channel, timestamp, text string) (string, string, string, error) {
+	return api.SendMessageContext(ctx, channel, MsgOptionUpdate(timestamp), MsgOptionText(text, true))
+}
+
+// SendMessage more flexible method for configuring messages.
+func (api *Client) SendMessage(channel string, options ...MsgOption) (string, string, string, error) {
+	return api.SendMessageContext(context.Background(), channel, options...)
+}
+
+// SendMessageContext more flexible method for configuring messages with a custom context.
+func (api *Client) SendMessageContext(ctx context.Context, channel string, options ...MsgOption) (string, string, string, error) {
+	channel, values, err := ApplyMsgOptions(api.config.token, channel, options...)
 	if err != nil {
-		return nil, err
+		return "", "", "", err
 	}
-	if !response.Ok {
-		return nil, errors.New(response.Error)
+
+	response, err := chatRequest(ctx, channel, values, api.debug)
+	if err != nil {
+		return "", "", "", err
 	}
-	return response, nil
+
+	return response.Channel, response.Timestamp, response.Text, 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},
+// ApplyMsgOptions utility function for debugging/testing chat requests.
+func ApplyMsgOptions(token, channel string, options ...MsgOption) (string, url.Values, error) {
+	config := sendConfig{
+		mode: chatPostMessage,
+		values: url.Values{
+			"token":   {token},
+			"channel": {channel},
+		},
 	}
-	response, err := chatRequest("chat.delete", values, api.debug)
-	if err != nil {
-		return "", "", err
+
+	for _, opt := range options {
+		if err := opt(&config); err != nil {
+			return string(config.mode), config.values, err
+		}
 	}
-	return response.Channel, response.Timestamp, nil
+
+	return string(config.mode), config.values, nil
 }
 
 func escapeMessage(message string) string {
@@ -93,79 +156,165 @@ func escapeMessage(message string) string {
 	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},
+func chatRequest(ctx context.Context, path string, values url.Values, debug bool) (*chatResponseFull, error) {
+	response := &chatResponseFull{}
+	err := post(ctx, path, values, response, debug)
+	if err != nil {
+		return nil, err
 	}
-	if params.Username != DEFAULT_MESSAGE_USERNAME {
-		values.Set("username", string(params.Username))
+	if !response.Ok {
+		return nil, errors.New(response.Error)
 	}
-	if params.AsUser != DEFAULT_MESSAGE_ASUSER {
-		values.Set("as_user", "true")
+	return response, nil
+}
+
+type sendMode string
+
+const (
+	chatUpdate      sendMode = "chat.update"
+	chatPostMessage sendMode = "chat.postMessage"
+	chatDelete      sendMode = "chat.delete"
+)
+
+type sendConfig struct {
+	mode   sendMode
+	values url.Values
+}
+
+// MsgOption option provided when sending a message.
+type MsgOption func(*sendConfig) error
+
+// MsgOptionPost posts a messages, this is the default.
+func MsgOptionPost() MsgOption {
+	return func(config *sendConfig) error {
+		config.mode = chatPostMessage
+		config.values.Del("ts")
+		return nil
 	}
-	if params.Parse != DEFAULT_MESSAGE_PARSE {
-		values.Set("parse", string(params.Parse))
+}
+
+// MsgOptionUpdate updates a message based on the timestamp.
+func MsgOptionUpdate(timestamp string) MsgOption {
+	return func(config *sendConfig) error {
+		config.mode = chatUpdate
+		config.values.Add("ts", timestamp)
+		return nil
 	}
-	if params.LinkNames != DEFAULT_MESSAGE_LINK_NAMES {
-		values.Set("link_names", "1")
+}
+
+// MsgOptionDelete deletes a message based on the timestamp.
+func MsgOptionDelete(timestamp string) MsgOption {
+	return func(config *sendConfig) error {
+		config.mode = chatDelete
+		config.values.Add("ts", timestamp)
+		return nil
 	}
-	if params.Attachments != nil {
-		attachments, err := json.Marshal(params.Attachments)
-		if err != nil {
-			return "", "", err
+}
+
+// MsgOptionAsUser whether or not to send the message as the user.
+func MsgOptionAsUser(b bool) MsgOption {
+	return func(config *sendConfig) error {
+		if b != DEFAULT_MESSAGE_ASUSER {
+			config.values.Set("as_user", "true")
 		}
-		values.Set("attachments", string(attachments))
+		return nil
 	}
-	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)
+}
+
+// MsgOptionText provide the text for the message, optionally escape the provided
+// text.
+func MsgOptionText(text string, escape bool) MsgOption {
+	return func(config *sendConfig) error {
+		if escape {
+			text = escapeMessage(text)
+		}
+		config.values.Add("text", text)
+		return nil
 	}
-	if params.Markdown != DEFAULT_MESSAGE_MARKDOWN {
-		values.Set("mrkdwn", "false")
+}
+
+// MsgOptionAttachments provide attachments for the message.
+func MsgOptionAttachments(attachments ...Attachment) MsgOption {
+	return func(config *sendConfig) error {
+		if attachments == nil {
+			return nil
+		}
+
+		attachments, err := json.Marshal(attachments)
+		if err == nil {
+			config.values.Set("attachments", string(attachments))
+		}
+		return err
 	}
-	if params.ThreadTimestamp != DEFAULT_MESSAGE_THREAD_TIMESTAMP {
-		values.Set("thread_ts", params.ThreadTimestamp)
+}
+
+// MsgOptionEnableLinkUnfurl enables link unfurling
+func MsgOptionEnableLinkUnfurl() MsgOption {
+	return func(config *sendConfig) error {
+		config.values.Set("unfurl_links", "true")
+		return nil
 	}
+}
 
-	response, err := chatRequest("chat.postMessage", values, api.debug)
-	if err != nil {
-		return "", "", err
+// MsgOptionDisableMediaUnfurl disables media unfurling.
+func MsgOptionDisableMediaUnfurl() MsgOption {
+	return func(config *sendConfig) error {
+		config.values.Set("unfurl_media", "false")
+		return nil
 	}
-	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},
+// MsgOptionDisableMarkdown disables markdown.
+func MsgOptionDisableMarkdown() MsgOption {
+	return func(config *sendConfig) error {
+		config.values.Set("mrkdwn", "false")
+		return nil
 	}
-	response, err := chatRequest("chat.update", values, api.debug)
-	if err != nil {
-		return "", "", "", err
+}
+
+// MsgOptionPostMessageParameters maintain backwards compatibility.
+func MsgOptionPostMessageParameters(params PostMessageParameters) MsgOption {
+	return func(config *sendConfig) error {
+		if params.Username != DEFAULT_MESSAGE_USERNAME {
+			config.values.Set("username", string(params.Username))
+		}
+
+		// never generates an error.
+		MsgOptionAsUser(params.AsUser)(config)
+
+		if params.Parse != DEFAULT_MESSAGE_PARSE {
+			config.values.Set("parse", string(params.Parse))
+		}
+		if params.LinkNames != DEFAULT_MESSAGE_LINK_NAMES {
+			config.values.Set("link_names", "1")
+		}
+
+		if params.UnfurlLinks != DEFAULT_MESSAGE_UNFURL_LINKS {
+			config.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 {
+			config.values.Set("unfurl_links", "false")
+		}
+		if params.UnfurlMedia != DEFAULT_MESSAGE_UNFURL_MEDIA {
+			config.values.Set("unfurl_media", "false")
+		}
+		if params.IconURL != DEFAULT_MESSAGE_ICON_URL {
+			config.values.Set("icon_url", params.IconURL)
+		}
+		if params.IconEmoji != DEFAULT_MESSAGE_ICON_EMOJI {
+			config.values.Set("icon_emoji", params.IconEmoji)
+		}
+		if params.Markdown != DEFAULT_MESSAGE_MARKDOWN {
+			config.values.Set("mrkdwn", "false")
+		}
+
+		if params.ThreadTimestamp != DEFAULT_MESSAGE_THREAD_TIMESTAMP {
+			config.values.Set("thread_ts", params.ThreadTimestamp)
+		}
+
+		return nil
 	}
-	return response.Channel, response.Timestamp, response.Text, nil
 }
diff --git a/vendor/github.com/nlopes/slack/dnd.go b/vendor/github.com/nlopes/slack/dnd.go
index ac87758d..4f1b3228 100644
--- a/vendor/github.com/nlopes/slack/dnd.go
+++ b/vendor/github.com/nlopes/slack/dnd.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -35,9 +36,9 @@ type dndTeamInfoResponse struct {
 	SlackResponse
 }
 
-func dndRequest(path string, values url.Values, debug bool) (*dndResponseFull, error) {
+func dndRequest(ctx context.Context, path string, values url.Values, debug bool) (*dndResponseFull, error) {
 	response := &dndResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -49,12 +50,17 @@ func dndRequest(path string, values url.Values, debug bool) (*dndResponseFull, e
 
 // EndDND ends the user's scheduled Do Not Disturb session
 func (api *Client) EndDND() error {
+	return api.EndDNDContext(context.Background())
+}
+
+// EndDNDContext ends the user's scheduled Do Not Disturb session with a custom context
+func (api *Client) EndDNDContext(ctx context.Context) error {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 
 	response := &SlackResponse{}
-	if err := post("dnd.endDnd", values, response, api.debug); err != nil {
+	if err := post(ctx, "dnd.endDnd", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -65,11 +71,16 @@ func (api *Client) EndDND() error {
 
 // EndSnooze ends the current user's snooze mode
 func (api *Client) EndSnooze() (*DNDStatus, error) {
+	return api.EndSnoozeContext(context.Background())
+}
+
+// EndSnoozeContext ends the current user's snooze mode with a custom context
+func (api *Client) EndSnoozeContext(ctx context.Context) (*DNDStatus, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 
-	response, err := dndRequest("dnd.endSnooze", values, api.debug)
+	response, err := dndRequest(ctx, "dnd.endSnooze", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -78,13 +89,18 @@ func (api *Client) EndSnooze() (*DNDStatus, error) {
 
 // GetDNDInfo provides information about a user's current Do Not Disturb settings.
 func (api *Client) GetDNDInfo(user *string) (*DNDStatus, error) {
+	return api.GetDNDInfoContext(context.Background(), user)
+}
+
+// GetDNDInfoContext provides information about a user's current Do Not Disturb settings with a custom context.
+func (api *Client) GetDNDInfoContext(ctx context.Context, 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)
+	response, err := dndRequest(ctx, "dnd.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -93,12 +109,17 @@ func (api *Client) GetDNDInfo(user *string) (*DNDStatus, error) {
 
 // GetDNDTeamInfo provides information about a user's current Do Not Disturb settings.
 func (api *Client) GetDNDTeamInfo(users []string) (map[string]DNDStatus, error) {
+	return api.GetDNDTeamInfoContext(context.Background(), users)
+}
+
+// GetDNDTeamInfoContext provides information about a user's current Do Not Disturb settings with a custom context.
+func (api *Client) GetDNDTeamInfoContext(ctx context.Context, 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 {
+	if err := post(ctx, "dnd.teamInfo", values, response, api.debug); err != nil {
 		return nil, err
 	}
 	if !response.Ok {
@@ -111,11 +132,17 @@ func (api *Client) GetDNDTeamInfo(users []string) (map[string]DNDStatus, error)
 // 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) {
+	return api.SetSnoozeContext(context.Background(), minutes)
+}
+
+// SetSnooze adjusts the snooze duration for a user's Do Not Disturb settings with a custom context.
+// For more information see the SetSnooze docs
+func (api *Client) SetSnoozeContext(ctx context.Context, minutes int) (*DNDStatus, error) {
 	values := url.Values{
 		"token":       {api.config.token},
 		"num_minutes": {strconv.Itoa(minutes)},
 	}
-	response, err := dndRequest("dnd.setSnooze", values, api.debug)
+	response, err := dndRequest(ctx, "dnd.setSnooze", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/emoji.go b/vendor/github.com/nlopes/slack/emoji.go
index 776c4a5f..5da9da41 100644
--- a/vendor/github.com/nlopes/slack/emoji.go
+++ b/vendor/github.com/nlopes/slack/emoji.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 )
@@ -12,11 +13,16 @@ type emojiResponseFull struct {
 
 // GetEmoji retrieves all the emojis
 func (api *Client) GetEmoji() (map[string]string, error) {
+	return api.GetEmojiContext(context.Background())
+}
+
+// GetEmojiContext retrieves all the emojis with a custom context
+func (api *Client) GetEmojiContext(ctx context.Context) (map[string]string, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 	response := &emojiResponseFull{}
-	err := post("emoji.list", values, response, api.debug)
+	err := post(ctx, "emoji.list", values, response, api.debug)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/examples/channels/channels.go b/vendor/github.com/nlopes/slack/examples/channels/channels.go
index a4465bdb..37d5f741 100644
--- a/vendor/github.com/nlopes/slack/examples/channels/channels.go
+++ b/vendor/github.com/nlopes/slack/examples/channels/channels.go
@@ -14,6 +14,8 @@ func main() {
 		return
 	}
 	for _, channel := range channels {
-		fmt.Println(channel.ID)
+		fmt.Println(channel.Name)
+		// channel is of type conversation & groupConversation
+		// see all available methods in `conversation.go`
 	}
 }
diff --git a/vendor/github.com/nlopes/slack/files.go b/vendor/github.com/nlopes/slack/files.go
index 18fc9ba9..fc4b7e23 100644
--- a/vendor/github.com/nlopes/slack/files.go
+++ b/vendor/github.com/nlopes/slack/files.go
@@ -1,7 +1,9 @@
 package slack
 
 import (
+	"context"
 	"errors"
+	"io"
 	"net/url"
 	"strconv"
 	"strings"
@@ -86,10 +88,14 @@ type File struct {
 	IsStarred       bool     `json:"is_starred"`
 }
 
-// FileUploadParameters contains all the parameters necessary (including the optional ones) for an UploadFile() request
+// FileUploadParameters contains all the parameters necessary (including the optional ones) for an UploadFile() request.
+//
+// There are three ways to upload a file. You can either set Content if file is small, set Reader if file is large,
+// or provide a local file path in File to upload it from your filesystem.
 type FileUploadParameters struct {
 	File           string
 	Content        string
+	Reader         io.Reader
 	Filetype       string
 	Filename       string
 	Title          string
@@ -130,9 +136,9 @@ func NewGetFilesParameters() GetFilesParameters {
 	}
 }
 
-func fileRequest(path string, values url.Values, debug bool) (*fileResponseFull, error) {
+func fileRequest(ctx context.Context, path string, values url.Values, debug bool) (*fileResponseFull, error) {
 	response := &fileResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -144,13 +150,18 @@ func fileRequest(path string, values url.Values, debug bool) (*fileResponseFull,
 
 // GetFileInfo retrieves a file and related comments
 func (api *Client) GetFileInfo(fileID string, count, page int) (*File, []Comment, *Paging, error) {
+	return api.GetFileInfoContext(context.Background(), fileID, count, page)
+}
+
+// GetFileInfoContext retrieves a file and related comments with a custom context
+func (api *Client) GetFileInfoContext(ctx context.Context, 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)
+	response, err := fileRequest(ctx, "files.info", values, api.debug)
 	if err != nil {
 		return nil, nil, nil, err
 	}
@@ -159,6 +170,11 @@ func (api *Client) GetFileInfo(fileID string, count, page int) (*File, []Comment
 
 // GetFiles retrieves all files according to the parameters given
 func (api *Client) GetFiles(params GetFilesParameters) ([]File, *Paging, error) {
+	return api.GetFilesContext(context.Background(), params)
+}
+
+// GetFilesContext retrieves all files according to the parameters given with a custom context
+func (api *Client) GetFilesContext(ctx context.Context, params GetFilesParameters) ([]File, *Paging, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -168,12 +184,11 @@ func (api *Client) GetFiles(params GetFilesParameters) ([]File, *Paging, error)
 	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())
+		values.Add("ts_from", strconv.FormatInt(int64(params.TimestampFrom), 10))
 	}
 	if params.TimestampTo != DEFAULT_FILES_TS_TO {
-		values.Add("ts_to", params.TimestampTo.String())
+		values.Add("ts_to", strconv.FormatInt(int64(params.TimestampTo), 10))
 	}
 	if params.Types != DEFAULT_FILES_TYPES {
 		values.Add("types", params.Types)
@@ -184,7 +199,7 @@ func (api *Client) GetFiles(params GetFilesParameters) ([]File, *Paging, error)
 	if params.Page != DEFAULT_FILES_PAGE {
 		values.Add("page", strconv.Itoa(params.Page))
 	}
-	response, err := fileRequest("files.list", values, api.debug)
+	response, err := fileRequest(ctx, "files.list", values, api.debug)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -193,6 +208,11 @@ func (api *Client) GetFiles(params GetFilesParameters) ([]File, *Paging, error)
 
 // UploadFile uploads a file
 func (api *Client) UploadFile(params FileUploadParameters) (file *File, err error) {
+	return api.UploadFileContext(context.Background(), params)
+}
+
+// UploadFileContext uploads a file and setting a custom context
+func (api *Client) UploadFileContext(ctx context.Context, 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()
@@ -220,9 +240,11 @@ func (api *Client) UploadFile(params FileUploadParameters) (file *File, err erro
 	}
 	if params.Content != "" {
 		values.Add("content", params.Content)
-		err = post("files.upload", values, response, api.debug)
+		err = post(ctx, "files.upload", values, response, api.debug)
 	} else if params.File != "" {
-		err = postWithMultipartResponse("files.upload", params.File, values, response, api.debug)
+		err = postLocalWithMultipartResponse(ctx, "files.upload", params.File, "file", values, response, api.debug)
+	} else if params.Reader != nil {
+		err = postWithMultipartResponse(ctx, "files.upload", params.Filename, "file", values, params.Reader, response, api.debug)
 	}
 	if err != nil {
 		return nil, err
@@ -235,11 +257,16 @@ func (api *Client) UploadFile(params FileUploadParameters) (file *File, err erro
 
 // DeleteFile deletes a file
 func (api *Client) DeleteFile(fileID string) error {
+	return api.DeleteFileContext(context.Background(), fileID)
+}
+
+// DeleteFileContext deletes a file with a custom context
+func (api *Client) DeleteFileContext(ctx context.Context, fileID string) error {
 	values := url.Values{
 		"token": {api.config.token},
 		"file":  {fileID},
 	}
-	_, err := fileRequest("files.delete", values, api.debug)
+	_, err := fileRequest(ctx, "files.delete", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -249,11 +276,16 @@ func (api *Client) DeleteFile(fileID string) error {
 
 // RevokeFilePublicURL disables public/external sharing for a file
 func (api *Client) RevokeFilePublicURL(fileID string) (*File, error) {
+	return api.RevokeFilePublicURLContext(context.Background(), fileID)
+}
+
+// RevokeFilePublicURLContext disables public/external sharing for a file with a custom context
+func (api *Client) RevokeFilePublicURLContext(ctx context.Context, fileID string) (*File, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"file":  {fileID},
 	}
-	response, err := fileRequest("files.revokePublicURL", values, api.debug)
+	response, err := fileRequest(ctx, "files.revokePublicURL", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -262,11 +294,16 @@ func (api *Client) RevokeFilePublicURL(fileID string) (*File, error) {
 
 // ShareFilePublicURL enabled public/external sharing for a file
 func (api *Client) ShareFilePublicURL(fileID string) (*File, []Comment, *Paging, error) {
+	return api.ShareFilePublicURLContext(context.Background(), fileID)
+}
+
+// ShareFilePublicURLContext enabled public/external sharing for a file with a custom context
+func (api *Client) ShareFilePublicURLContext(ctx context.Context, fileID string) (*File, []Comment, *Paging, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"file":  {fileID},
 	}
-	response, err := fileRequest("files.sharedPublicURL", values, api.debug)
+	response, err := fileRequest(ctx, "files.sharedPublicURL", values, api.debug)
 	if err != nil {
 		return nil, nil, nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/groups.go b/vendor/github.com/nlopes/slack/groups.go
index ec4a3b65..444666dd 100644
--- a/vendor/github.com/nlopes/slack/groups.go
+++ b/vendor/github.com/nlopes/slack/groups.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -27,9 +28,9 @@ type groupResponseFull struct {
 	SlackResponse
 }
 
-func groupRequest(path string, values url.Values, debug bool) (*groupResponseFull, error) {
+func groupRequest(ctx context.Context, path string, values url.Values, debug bool) (*groupResponseFull, error) {
 	response := &groupResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -41,11 +42,16 @@ func groupRequest(path string, values url.Values, debug bool) (*groupResponseFul
 
 // ArchiveGroup archives a private group
 func (api *Client) ArchiveGroup(group string) error {
+	return api.ArchiveGroupContext(context.Background(), group)
+}
+
+// ArchiveGroup archives a private group
+func (api *Client) ArchiveGroupContext(ctx context.Context, group string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	_, err := groupRequest("groups.archive", values, api.debug)
+	_, err := groupRequest(ctx, "groups.archive", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -54,11 +60,16 @@ func (api *Client) ArchiveGroup(group string) error {
 
 // UnarchiveGroup unarchives a private group
 func (api *Client) UnarchiveGroup(group string) error {
+	return api.UnarchiveGroupContext(context.Background(), group)
+}
+
+// UnarchiveGroup unarchives a private group
+func (api *Client) UnarchiveGroupContext(ctx context.Context, group string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	_, err := groupRequest("groups.unarchive", values, api.debug)
+	_, err := groupRequest(ctx, "groups.unarchive", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -67,11 +78,16 @@ func (api *Client) UnarchiveGroup(group string) error {
 
 // CreateGroup creates a private group
 func (api *Client) CreateGroup(group string) (*Group, error) {
+	return api.CreateGroupContext(context.Background(), group)
+}
+
+// CreateGroup creates a private group
+func (api *Client) CreateGroupContext(ctx context.Context, group string) (*Group, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"name":  {group},
 	}
-	response, err := groupRequest("groups.create", values, api.debug)
+	response, err := groupRequest(ctx, "groups.create", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -85,11 +101,17 @@ func (api *Client) CreateGroup(group string) (*Group, error) {
 //   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) {
+	return api.CreateChildGroupContext(context.Background(), group)
+}
+
+// CreateChildGroup creates a new private group archiving the old one with a custom context
+// For more information see CreateChildGroup
+func (api *Client) CreateChildGroupContext(ctx context.Context, group string) (*Group, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	response, err := groupRequest("groups.createChild", values, api.debug)
+	response, err := groupRequest(ctx, "groups.createChild", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -98,11 +120,16 @@ func (api *Client) CreateChildGroup(group string) (*Group, error) {
 
 // CloseGroup closes a private group
 func (api *Client) CloseGroup(group string) (bool, bool, error) {
+	return api.CloseGroupContext(context.Background(), group)
+}
+
+// CloseGroupContext closes a private group with a custom context
+func (api *Client) CloseGroupContext(ctx context.Context, group string) (bool, bool, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	response, err := imRequest("groups.close", values, api.debug)
+	response, err := imRequest(ctx, "groups.close", values, api.debug)
 	if err != nil {
 		return false, false, err
 	}
@@ -111,6 +138,11 @@ func (api *Client) CloseGroup(group string) (bool, bool, error) {
 
 // GetGroupHistory fetches all the history for a private group
 func (api *Client) GetGroupHistory(group string, params HistoryParameters) (*History, error) {
+	return api.GetGroupHistoryContext(context.Background(), group, params)
+}
+
+// GetGroupHistoryContext fetches all the history for a private group with a custom context
+func (api *Client) GetGroupHistoryContext(ctx context.Context, group string, params HistoryParameters) (*History, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
@@ -138,7 +170,7 @@ func (api *Client) GetGroupHistory(group string, params HistoryParameters) (*His
 			values.Add("unreads", "0")
 		}
 	}
-	response, err := groupRequest("groups.history", values, api.debug)
+	response, err := groupRequest(ctx, "groups.history", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -147,12 +179,17 @@ func (api *Client) GetGroupHistory(group string, params HistoryParameters) (*His
 
 // InviteUserToGroup invites a specific user to a private group
 func (api *Client) InviteUserToGroup(group, user string) (*Group, bool, error) {
+	return api.InviteUserToGroupContext(context.Background(), group, user)
+}
+
+// InviteUserToGroupContext invites a specific user to a private group with a custom context
+func (api *Client) InviteUserToGroupContext(ctx context.Context, 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)
+	response, err := groupRequest(ctx, "groups.invite", values, api.debug)
 	if err != nil {
 		return nil, false, err
 	}
@@ -161,11 +198,16 @@ func (api *Client) InviteUserToGroup(group, user string) (*Group, bool, error) {
 
 // LeaveGroup makes authenticated user leave the group
 func (api *Client) LeaveGroup(group string) error {
+	return api.LeaveGroupContext(context.Background(), group)
+}
+
+// LeaveGroupContext makes authenticated user leave the group with a custom context
+func (api *Client) LeaveGroupContext(ctx context.Context, group string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	_, err := groupRequest("groups.leave", values, api.debug)
+	_, err := groupRequest(ctx, "groups.leave", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -174,12 +216,17 @@ func (api *Client) LeaveGroup(group string) error {
 
 // KickUserFromGroup kicks a user from a group
 func (api *Client) KickUserFromGroup(group, user string) error {
+	return api.KickUserFromGroupContext(context.Background(), group, user)
+}
+
+// KickUserFromGroupContext kicks a user from a group with a custom context
+func (api *Client) KickUserFromGroupContext(ctx context.Context, group, user string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 		"user":    {user},
 	}
-	_, err := groupRequest("groups.kick", values, api.debug)
+	_, err := groupRequest(ctx, "groups.kick", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -188,13 +235,18 @@ func (api *Client) KickUserFromGroup(group, user string) error {
 
 // GetGroups retrieves all groups
 func (api *Client) GetGroups(excludeArchived bool) ([]Group, error) {
+	return api.GetGroupsContext(context.Background(), excludeArchived)
+}
+
+// GetGroupsContext retrieves all groups with a custom context
+func (api *Client) GetGroupsContext(ctx context.Context, 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)
+	response, err := groupRequest(ctx, "groups.list", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -203,11 +255,16 @@ func (api *Client) GetGroups(excludeArchived bool) ([]Group, error) {
 
 // GetGroupInfo retrieves the given group
 func (api *Client) GetGroupInfo(group string) (*Group, error) {
+	return api.GetGroupInfoContext(context.Background(), group)
+}
+
+// GetGroupInfoContext retrieves the given group with a custom context
+func (api *Client) GetGroupInfoContext(ctx context.Context, group string) (*Group, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	response, err := groupRequest("groups.info", values, api.debug)
+	response, err := groupRequest(ctx, "groups.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -220,12 +277,18 @@ func (api *Client) GetGroupInfo(group string) (*Group, error) {
 // 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 {
+	return api.SetGroupReadMarkContext(context.Background(), group, ts)
+}
+
+// SetGroupReadMarkContext sets the read mark on a private group with a custom context
+// For more details see SetGroupReadMark
+func (api *Client) SetGroupReadMarkContext(ctx context.Context, group, ts string) error {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 		"ts":      {ts},
 	}
-	_, err := groupRequest("groups.mark", values, api.debug)
+	_, err := groupRequest(ctx, "groups.mark", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -234,11 +297,16 @@ func (api *Client) SetGroupReadMark(group, ts string) error {
 
 // OpenGroup opens a private group
 func (api *Client) OpenGroup(group string) (bool, bool, error) {
+	return api.OpenGroupContext(context.Background(), group)
+}
+
+// OpenGroupContext opens a private group with a custom context
+func (api *Client) OpenGroupContext(ctx context.Context, group string) (bool, bool, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 	}
-	response, err := groupRequest("groups.open", values, api.debug)
+	response, err := groupRequest(ctx, "groups.open", values, api.debug)
 	if err != nil {
 		return false, false, err
 	}
@@ -249,6 +317,11 @@ func (api *Client) OpenGroup(group string) (bool, bool, error) {
 // 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) {
+	return api.RenameGroupContext(context.Background(), group, name)
+}
+
+// RenameGroupContext renames a group with a custom context
+func (api *Client) RenameGroupContext(ctx context.Context, group, name string) (*Channel, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
@@ -256,22 +329,26 @@ func (api *Client) RenameGroup(group, name string) (*Channel, error) {
 	}
 	// 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)
+	response, err := groupRequest(ctx, "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) {
+	return api.SetGroupPurposeContext(context.Background(), group, purpose)
+}
+
+// SetGroupPurposeContext sets the group purpose with a custom context
+func (api *Client) SetGroupPurposeContext(ctx context.Context, group, purpose string) (string, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 		"purpose": {purpose},
 	}
-	response, err := groupRequest("groups.setPurpose", values, api.debug)
+	response, err := groupRequest(ctx, "groups.setPurpose", values, api.debug)
 	if err != nil {
 		return "", err
 	}
@@ -280,12 +357,17 @@ func (api *Client) SetGroupPurpose(group, purpose string) (string, error) {
 
 // SetGroupTopic sets the group topic
 func (api *Client) SetGroupTopic(group, topic string) (string, error) {
+	return api.SetGroupTopicContext(context.Background(), group, topic)
+}
+
+// SetGroupTopicContext sets the group topic with a custom context
+func (api *Client) SetGroupTopicContext(ctx context.Context, group, topic string) (string, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {group},
 		"topic":   {topic},
 	}
-	response, err := groupRequest("groups.setTopic", values, api.debug)
+	response, err := groupRequest(ctx, "groups.setTopic", values, api.debug)
 	if err != nil {
 		return "", err
 	}
diff --git a/vendor/github.com/nlopes/slack/im.go b/vendor/github.com/nlopes/slack/im.go
index 6fbc39e9..0cbc8d34 100644
--- a/vendor/github.com/nlopes/slack/im.go
+++ b/vendor/github.com/nlopes/slack/im.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -28,9 +29,9 @@ type IM struct {
 	IsUserDeleted bool   `json:"is_user_deleted"`
 }
 
-func imRequest(path string, values url.Values, debug bool) (*imResponseFull, error) {
+func imRequest(ctx context.Context, path string, values url.Values, debug bool) (*imResponseFull, error) {
 	response := &imResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -42,11 +43,16 @@ func imRequest(path string, values url.Values, debug bool) (*imResponseFull, err
 
 // CloseIMChannel closes the direct message channel
 func (api *Client) CloseIMChannel(channel string) (bool, bool, error) {
+	return api.CloseIMChannelContext(context.Background(), channel)
+}
+
+// CloseIMChannelContext closes the direct message channel with a custom context
+func (api *Client) CloseIMChannelContext(ctx context.Context, channel string) (bool, bool, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 	}
-	response, err := imRequest("im.close", values, api.debug)
+	response, err := imRequest(ctx, "im.close", values, api.debug)
 	if err != nil {
 		return false, false, err
 	}
@@ -56,11 +62,17 @@ func (api *Client) CloseIMChannel(channel string) (bool, bool, error) {
 // 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) {
+	return api.OpenIMChannelContext(context.Background(), user)
+}
+
+// OpenIMChannelContext opens a direct message channel to the user provided as argument with a custom context
+// Returns some status and the channel ID
+func (api *Client) OpenIMChannelContext(ctx context.Context, user string) (bool, bool, string, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"user":  {user},
 	}
-	response, err := imRequest("im.open", values, api.debug)
+	response, err := imRequest(ctx, "im.open", values, api.debug)
 	if err != nil {
 		return false, false, "", err
 	}
@@ -69,12 +81,17 @@ func (api *Client) OpenIMChannel(user string) (bool, bool, string, error) {
 
 // MarkIMChannel sets the read mark of a direct message channel to a specific point
 func (api *Client) MarkIMChannel(channel, ts string) (err error) {
+	return api.MarkIMChannelContext(context.Background(), channel, ts)
+}
+
+// MarkIMChannelContext sets the read mark of a direct message channel to a specific point with a custom context
+func (api *Client) MarkIMChannelContext(ctx context.Context, channel, ts string) (err error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
 		"ts":      {ts},
 	}
-	_, err = imRequest("im.mark", values, api.debug)
+	_, err = imRequest(ctx, "im.mark", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -83,6 +100,11 @@ func (api *Client) MarkIMChannel(channel, ts string) (err error) {
 
 // GetIMHistory retrieves the direct message channel history
 func (api *Client) GetIMHistory(channel string, params HistoryParameters) (*History, error) {
+	return api.GetIMHistoryContext(context.Background(), channel, params)
+}
+
+// GetIMHistoryContext retrieves the direct message channel history with a custom context
+func (api *Client) GetIMHistoryContext(ctx context.Context, channel string, params HistoryParameters) (*History, error) {
 	values := url.Values{
 		"token":   {api.config.token},
 		"channel": {channel},
@@ -110,7 +132,7 @@ func (api *Client) GetIMHistory(channel string, params HistoryParameters) (*Hist
 			values.Add("unreads", "0")
 		}
 	}
-	response, err := imRequest("im.history", values, api.debug)
+	response, err := imRequest(ctx, "im.history", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -119,10 +141,15 @@ func (api *Client) GetIMHistory(channel string, params HistoryParameters) (*Hist
 
 // GetIMChannels returns the list of direct message channels
 func (api *Client) GetIMChannels() ([]IM, error) {
+	return api.GetIMChannelsContext(context.Background())
+}
+
+// GetIMChannelsContext returns the list of direct message channels with a custom context
+func (api *Client) GetIMChannelsContext(ctx context.Context) ([]IM, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
-	response, err := imRequest("im.list", values, api.debug)
+	response, err := imRequest(ctx, "im.list", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/messages.go b/vendor/github.com/nlopes/slack/messages.go
index 3433e06b..39f0d6b1 100644
--- a/vendor/github.com/nlopes/slack/messages.go
+++ b/vendor/github.com/nlopes/slack/messages.go
@@ -2,10 +2,11 @@ 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"`
+	ID              int    `json:"id"`
+	Channel         string `json:"channel,omitempty"`
+	Text            string `json:"text,omitempty"`
+	Type            string `json:"type,omitempty"`
+	ThreadTimestamp string `json:"thread_ts,omitempty"`
 }
 
 // Message is an auxiliary type to allow us to have a message containing sub messages
@@ -17,15 +18,16 @@ type Message struct {
 // 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"`
+	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"`
+	ThreadTimestamp string       `json:"thread_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"`
@@ -56,6 +58,11 @@ type Msg struct {
 	// channel_archive, group_archive
 	Members []string `json:"members,omitempty"`
 
+	// channels.replies, groups.replies, im.replies, mpim.replies
+	ReplyCount   int     `json:"reply_count,omitempty"`
+	Replies      []Reply `json:"replies,omitempty"`
+	ParentUserId string  `json:"parent_user_id,omitempty"`
+
 	// file_share, file_comment, file_mention
 	File *File `json:"file,omitempty"`
 
@@ -88,6 +95,12 @@ type Edited struct {
 	Timestamp string `json:"ts,omitempty"`
 }
 
+// Reply contains information about a reply for a thread
+type Reply struct {
+	User      string `json:"user,omitempty"`
+	Timestamp string `json:"ts,omitempty"`
+}
+
 // Event contains the event type
 type Event struct {
 	Type string `json:"type,omitempty"`
diff --git a/vendor/github.com/nlopes/slack/misc.go b/vendor/github.com/nlopes/slack/misc.go
index 57f39104..3a9ed2d6 100644
--- a/vendor/github.com/nlopes/slack/misc.go
+++ b/vendor/github.com/nlopes/slack/misc.go
@@ -2,8 +2,8 @@ package slack
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -13,9 +13,22 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"strings"
 	"time"
 )
 
+// HTTPRequester defines the minimal interface needed for an http.Client to be implemented.
+//
+// Use it in conjunction with the SetHTTPClient function to allow for other capabilities
+// like a tracing http.Client
+type HTTPRequester interface {
+	Do(*http.Request) (*http.Response, error)
+}
+
+var customHTTPClient HTTPRequester
+
+// HTTPClient sets a custom http.Client
+// deprecated: in favor of SetHTTPClient()
 var HTTPClient = &http.Client{}
 
 type WebResponse struct {
@@ -29,40 +42,24 @@ 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()
-
+func fileUploadReq(ctx context.Context, path, fieldname, filename string, values url.Values, r io.Reader) (*http.Request, error) {
 	body := &bytes.Buffer{}
 	wr := multipart.NewWriter(body)
 
-	ioWriter, err := wr.CreateFormFile("file", filepath.Base(fullpath))
+	ioWriter, err := wr.CreateFormFile(fieldname, filename)
 	if err != nil {
 		wr.Close()
 		return nil, err
 	}
-	bytes, err := io.Copy(ioWriter, file)
+	_, err = io.Copy(ioWriter, r)
 	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)
+	req = req.WithContext(ctx)
 	if err != nil {
 		return nil, err
 	}
@@ -90,9 +87,26 @@ func parseResponseBody(body io.ReadCloser, intf *interface{}, debug bool) error
 	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)
+func postLocalWithMultipartResponse(ctx context.Context, path, fpath, fieldname string, values url.Values, intf interface{}, debug bool) error {
+	fullpath, err := filepath.Abs(fpath)
+	if err != nil {
+		return err
+	}
+	file, err := os.Open(fullpath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	return postWithMultipartResponse(ctx, path, filepath.Base(fpath), fieldname, values, file, intf, debug)
+}
+
+func postWithMultipartResponse(ctx context.Context, path, name, fieldname string, values url.Values, r io.Reader, intf interface{}, debug bool) error {
+	req, err := fileUploadReq(ctx, SLACK_API+path, fieldname, name, values, r)
+	if err != nil {
+		return err
+	}
+	req = req.WithContext(ctx)
+	resp, err := getHTTPClient().Do(req)
 	if err != nil {
 		return err
 	}
@@ -107,23 +121,37 @@ func postWithMultipartResponse(path string, filepath string, values url.Values,
 	return parseResponseBody(resp.Body, &intf, debug)
 }
 
-func postForm(endpoint string, values url.Values, intf interface{}, debug bool) error {
-	resp, err := HTTPClient.PostForm(endpoint, values)
+func postForm(ctx context.Context, endpoint string, values url.Values, intf interface{}, debug bool) error {
+	reqBody := strings.NewReader(values.Encode())
+	req, err := http.NewRequest("POST", endpoint, reqBody)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	req = req.WithContext(ctx)
+	resp, err := getHTTPClient().Do(req)
 	if err != nil {
 		return err
 	}
 	defer resp.Body.Close()
 
+	// Slack seems to send an HTML body along with 5xx error codes. Don't parse it.
+	if resp.StatusCode != 200 {
+		logResponse(resp, debug)
+		return fmt.Errorf("Slack server error: %s.", resp.Status)
+	}
+
 	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 post(ctx context.Context, path string, values url.Values, intf interface{}, debug bool) error {
+	return postForm(ctx, SLACK_API+path, values, intf, debug)
 }
 
-func parseAdminResponse(method string, teamName string, values url.Values, intf interface{}, debug bool) error {
+func parseAdminResponse(ctx context.Context, 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)
+	return postForm(ctx, endpoint, values, intf, debug)
 }
 
 func logResponse(resp *http.Response, debug bool) error {
@@ -133,8 +161,23 @@ func logResponse(resp *http.Response, debug bool) error {
 			return err
 		}
 
-		logger.Print(text)
+		logger.Print(string(text))
 	}
 
 	return nil
 }
+
+func getHTTPClient() HTTPRequester {
+	if customHTTPClient != nil {
+		return customHTTPClient
+	}
+
+	return HTTPClient
+}
+
+// SetHTTPClient allows you to specify a custom http.Client
+// Use this instead of the package level HTTPClient variable if you want to use a custom client like the
+// Stackdriver Trace HTTPClient https://godoc.org/cloud.google.com/go/trace#HTTPClient
+func SetHTTPClient(client HTTPRequester) {
+	customHTTPClient = client
+}
diff --git a/vendor/github.com/nlopes/slack/oauth.go b/vendor/github.com/nlopes/slack/oauth.go
index 1285abbd..db10aa1b 100644
--- a/vendor/github.com/nlopes/slack/oauth.go
+++ b/vendor/github.com/nlopes/slack/oauth.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 )
@@ -30,7 +31,12 @@ type OAuthResponse struct {
 
 // 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)
+	return GetOAuthTokenContext(context.Background(), clientID, clientSecret, code, redirectURI, debug)
+}
+
+// GetOAuthTokenContext retrieves an AccessToken with a custom context
+func GetOAuthTokenContext(ctx context.Context, clientID, clientSecret, code, redirectURI string, debug bool) (accessToken string, scope string, err error) {
+	response, err := GetOAuthResponseContext(ctx, clientID, clientSecret, code, redirectURI, debug)
 	if err != nil {
 		return "", "", err
 	}
@@ -38,6 +44,10 @@ func GetOAuthToken(clientID, clientSecret, code, redirectURI string, debug bool)
 }
 
 func GetOAuthResponse(clientID, clientSecret, code, redirectURI string, debug bool) (resp *OAuthResponse, err error) {
+	return GetOAuthResponseContext(context.Background(), clientID, clientSecret, code, redirectURI, debug)
+}
+
+func GetOAuthResponseContext(ctx context.Context, clientID, clientSecret, code, redirectURI string, debug bool) (resp *OAuthResponse, err error) {
 	values := url.Values{
 		"client_id":     {clientID},
 		"client_secret": {clientSecret},
@@ -45,7 +55,7 @@ func GetOAuthResponse(clientID, clientSecret, code, redirectURI string, debug bo
 		"redirect_uri":  {redirectURI},
 	}
 	response := &OAuthResponse{}
-	err = post("oauth.access", values, response, debug)
+	err = post(ctx, "oauth.access", values, response, debug)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/pins.go b/vendor/github.com/nlopes/slack/pins.go
index b95efbb6..a20f8f73 100644
--- a/vendor/github.com/nlopes/slack/pins.go
+++ b/vendor/github.com/nlopes/slack/pins.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 )
@@ -13,6 +14,11 @@ type listPinsResponseFull struct {
 
 // AddPin pins an item in a channel
 func (api *Client) AddPin(channel string, item ItemRef) error {
+	return api.AddPinContext(context.Background(), channel, item)
+}
+
+// AddPinContext pins an item in a channel with a custom context
+func (api *Client) AddPinContext(ctx context.Context, channel string, item ItemRef) error {
 	values := url.Values{
 		"channel": {channel},
 		"token":   {api.config.token},
@@ -27,7 +33,7 @@ func (api *Client) AddPin(channel string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("pins.add", values, response, api.debug); err != nil {
+	if err := post(ctx, "pins.add", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -38,6 +44,11 @@ func (api *Client) AddPin(channel string, item ItemRef) error {
 
 // RemovePin un-pins an item from a channel
 func (api *Client) RemovePin(channel string, item ItemRef) error {
+	return api.RemovePinContext(context.Background(), channel, item)
+}
+
+// RemovePinContext un-pins an item from a channel with a custom context
+func (api *Client) RemovePinContext(ctx context.Context, channel string, item ItemRef) error {
 	values := url.Values{
 		"channel": {channel},
 		"token":   {api.config.token},
@@ -52,7 +63,7 @@ func (api *Client) RemovePin(channel string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("pins.remove", values, response, api.debug); err != nil {
+	if err := post(ctx, "pins.remove", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -63,12 +74,17 @@ func (api *Client) RemovePin(channel string, item ItemRef) error {
 
 // ListPins returns information about the items a user reacted to.
 func (api *Client) ListPins(channel string) ([]Item, *Paging, error) {
+	return api.ListPinsContext(context.Background(), channel)
+}
+
+// ListPinsContext returns information about the items a user reacted to with a custom context.
+func (api *Client) ListPinsContext(ctx context.Context, channel string) ([]Item, *Paging, error) {
 	values := url.Values{
 		"channel": {channel},
 		"token":   {api.config.token},
 	}
 	response := &listPinsResponseFull{}
-	err := post("pins.list", values, response, api.debug)
+	err := post(ctx, "pins.list", values, response, api.debug)
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/reactions.go b/vendor/github.com/nlopes/slack/reactions.go
index 8769543d..9da59241 100644
--- a/vendor/github.com/nlopes/slack/reactions.go
+++ b/vendor/github.com/nlopes/slack/reactions.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -129,6 +130,11 @@ func (res listReactionsResponseFull) extractReactedItems() []ReactedItem {
 
 // AddReaction adds a reaction emoji to a message, file or file comment.
 func (api *Client) AddReaction(name string, item ItemRef) error {
+	return api.AddReactionContext(context.Background(), name, item)
+}
+
+// AddReactionContext adds a reaction emoji to a message, file or file comment with a custom context.
+func (api *Client) AddReactionContext(ctx context.Context, name string, item ItemRef) error {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -148,7 +154,7 @@ func (api *Client) AddReaction(name string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("reactions.add", values, response, api.debug); err != nil {
+	if err := post(ctx, "reactions.add", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -159,6 +165,11 @@ func (api *Client) AddReaction(name string, item ItemRef) error {
 
 // RemoveReaction removes a reaction emoji from a message, file or file comment.
 func (api *Client) RemoveReaction(name string, item ItemRef) error {
+	return api.RemoveReactionContext(context.Background(), name, item)
+}
+
+// RemoveReactionContext removes a reaction emoji from a message, file or file comment with a custom context.
+func (api *Client) RemoveReactionContext(ctx context.Context, name string, item ItemRef) error {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -178,7 +189,7 @@ func (api *Client) RemoveReaction(name string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("reactions.remove", values, response, api.debug); err != nil {
+	if err := post(ctx, "reactions.remove", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -189,6 +200,11 @@ func (api *Client) RemoveReaction(name string, item ItemRef) error {
 
 // GetReactions returns details about the reactions on an item.
 func (api *Client) GetReactions(item ItemRef, params GetReactionsParameters) ([]ItemReaction, error) {
+	return api.GetReactionsContext(context.Background(), item, params)
+}
+
+// GetReactionsContext returns details about the reactions on an item with a custom context
+func (api *Client) GetReactionsContext(ctx context.Context, item ItemRef, params GetReactionsParameters) ([]ItemReaction, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -208,7 +224,7 @@ func (api *Client) GetReactions(item ItemRef, params GetReactionsParameters) ([]
 		values.Set("full", strconv.FormatBool(params.Full))
 	}
 	response := &getReactionsResponseFull{}
-	if err := post("reactions.get", values, response, api.debug); err != nil {
+	if err := post(ctx, "reactions.get", values, response, api.debug); err != nil {
 		return nil, err
 	}
 	if !response.Ok {
@@ -219,6 +235,11 @@ func (api *Client) GetReactions(item ItemRef, params GetReactionsParameters) ([]
 
 // ListReactions returns information about the items a user reacted to.
 func (api *Client) ListReactions(params ListReactionsParameters) ([]ReactedItem, *Paging, error) {
+	return api.ListReactionsContext(context.Background(), params)
+}
+
+// ListReactionsContext returns information about the items a user reacted to with a custom context.
+func (api *Client) ListReactionsContext(ctx context.Context, params ListReactionsParameters) ([]ReactedItem, *Paging, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -235,7 +256,7 @@ func (api *Client) ListReactions(params ListReactionsParameters) ([]ReactedItem,
 		values.Add("full", strconv.FormatBool(params.Full))
 	}
 	response := &listReactionsResponseFull{}
-	err := post("reactions.list", values, response, api.debug)
+	err := post(ctx, "reactions.list", values, response, api.debug)
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/rtm.go b/vendor/github.com/nlopes/slack/rtm.go
index f3552c53..fd5d2002 100644
--- a/vendor/github.com/nlopes/slack/rtm.go
+++ b/vendor/github.com/nlopes/slack/rtm.go
@@ -1,18 +1,58 @@
 package slack
 
 import (
+	"context"
+	"encoding/json"
 	"fmt"
 	"net/url"
+	"time"
 )
 
-// StartRTM calls the "rtm.start" endpoint and returns the provided URL and the full Info
-// block.
+// 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.
+// To have a fully managed Websocket connection, use `NewRTM`, and call `ManageConnection()` on it.
 func (api *Client) StartRTM() (info *Info, websocketURL string, err error) {
+	return api.StartRTMContext(context.Background())
+}
+
+// StartRTMContext calls the "rtm.start" endpoint and returns the provided URL and the full Info block with a custom context.
+//
+// To have a fully managed Websocket connection, use `NewRTM`, and call `ManageConnection()` on it.
+func (api *Client) StartRTMContext(ctx context.Context) (info *Info, websocketURL string, err error) {
 	response := &infoResponseFull{}
-	err = post("rtm.start", url.Values{"token": {api.config.token}}, response, api.debug)
+	err = post(ctx, "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
+}
+
+// ConnectRTM calls the "rtm.connect" endpoint and returns the provided URL and the compact Info block.
+//
+// To have a fully managed Websocket connection, use `NewRTM`, and call `ManageConnection()` on it.
+func (api *Client) ConnectRTM() (info *Info, websocketURL string, err error) {
+	return api.ConnectRTMContext(context.Background())
+}
+
+// ConnectRTM calls the "rtm.connect" endpoint and returns the provided URL and the compact Info block with a custom context.
+//
+// To have a fully managed Websocket connection, use `NewRTM`, and call `ManageConnection()` on it.
+func (api *Client) ConnectRTMContext(ctx context.Context) (info *Info, websocketURL string, err error) {
+	response := &infoResponseFull{}
+	err = post(ctx, "rtm.connect", url.Values{"token": {api.config.token}}, response, api.debug)
 	if err != nil {
 		return nil, "", fmt.Errorf("post: %s", err)
 	}
@@ -33,7 +73,33 @@ func (api *Client) StartRTM() (info *Info, websocketURL string, err error) {
 }
 
 // NewRTM returns a RTM, which provides a fully managed connection to
-// Slack's websocket-based Real-Time Messaging protocol./
+// Slack's websocket-based Real-Time Messaging protocol.
 func (api *Client) NewRTM() *RTM {
-	return newRTM(api)
+	return api.NewRTMWithOptions(nil)
+}
+
+// NewRTMWithOptions returns a RTM, which provides a fully managed connection to
+// Slack's websocket-based Real-Time Messaging protocol.
+// This also allows to configure various options available for RTM API.
+func (api *Client) NewRTMWithOptions(options *RTMOptions) *RTM {
+	result := &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),
+	}
+
+	if options != nil {
+		result.useRTMStart = options.UseRTMStart
+	} else {
+		result.useRTMStart = true
+	}
+
+	return result
 }
diff --git a/vendor/github.com/nlopes/slack/search.go b/vendor/github.com/nlopes/slack/search.go
index ab3c5dad..0e8d65e2 100644
--- a/vendor/github.com/nlopes/slack/search.go
+++ b/vendor/github.com/nlopes/slack/search.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -80,7 +81,7 @@ func NewSearchParameters() SearchParameters {
 	}
 }
 
-func (api *Client) _search(path, query string, params SearchParameters, files, messages bool) (response *searchResponseFull, error error) {
+func (api *Client) _search(ctx context.Context, path, query string, params SearchParameters, files, messages bool) (response *searchResponseFull, error error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"query": {query},
@@ -101,7 +102,7 @@ func (api *Client) _search(path, query string, params SearchParameters, files, m
 		values.Add("page", strconv.Itoa(params.Page))
 	}
 	response = &searchResponseFull{}
-	err := post(path, values, response, api.debug)
+	err := post(ctx, path, values, response, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -113,7 +114,11 @@ func (api *Client) _search(path, query string, params SearchParameters, files, m
 }
 
 func (api *Client) Search(query string, params SearchParameters) (*SearchMessages, *SearchFiles, error) {
-	response, err := api._search("search.all", query, params, true, true)
+	return api.SearchContext(context.Background(), query, params)
+}
+
+func (api *Client) SearchContext(ctx context.Context, query string, params SearchParameters) (*SearchMessages, *SearchFiles, error) {
+	response, err := api._search(ctx, "search.all", query, params, true, true)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -121,7 +126,11 @@ func (api *Client) Search(query string, params SearchParameters) (*SearchMessage
 }
 
 func (api *Client) SearchFiles(query string, params SearchParameters) (*SearchFiles, error) {
-	response, err := api._search("search.files", query, params, true, false)
+	return api.SearchFilesContext(context.Background(), query, params)
+}
+
+func (api *Client) SearchFilesContext(ctx context.Context, query string, params SearchParameters) (*SearchFiles, error) {
+	response, err := api._search(ctx, "search.files", query, params, true, false)
 	if err != nil {
 		return nil, err
 	}
@@ -129,7 +138,11 @@ func (api *Client) SearchFiles(query string, params SearchParameters) (*SearchFi
 }
 
 func (api *Client) SearchMessages(query string, params SearchParameters) (*SearchMessages, error) {
-	response, err := api._search("search.messages", query, params, false, true)
+	return api.SearchMessagesContext(context.Background(), query, params)
+}
+
+func (api *Client) SearchMessagesContext(ctx context.Context, query string, params SearchParameters) (*SearchMessages, error) {
+	response, err := api._search(ctx, "search.messages", query, params, false, true)
 	if err != nil {
 		return nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/slack.go b/vendor/github.com/nlopes/slack/slack.go
index eb686354..a13bed31 100644
--- a/vendor/github.com/nlopes/slack/slack.go
+++ b/vendor/github.com/nlopes/slack/slack.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"log"
 	"net/url"
@@ -54,8 +55,13 @@ func New(token string) *Client {
 
 // AuthTest tests if the user is able to do authenticated requests or not
 func (api *Client) AuthTest() (response *AuthTestResponse, error error) {
+	return api.AuthTestContext(context.Background())
+}
+
+// AuthTestContext tests if the user is able to do authenticated requests or not with a custom context
+func (api *Client) AuthTestContext(ctx context.Context) (response *AuthTestResponse, error error) {
 	responseFull := &authTestResponseFull{}
-	err := post("auth.test", url.Values{"token": {api.config.token}}, responseFull, api.debug)
+	err := post(ctx, "auth.test", url.Values{"token": {api.config.token}}, responseFull, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -71,7 +77,7 @@ func (api *Client) AuthTest() (response *AuthTestResponse, error error) {
 func (api *Client) SetDebug(debug bool) {
 	api.debug = debug
 	if debug && logger == nil {
-		logger = log.New(os.Stdout, "nlopes/slack", log.LstdFlags | log.Lshortfile)
+		logger = log.New(os.Stdout, "nlopes/slack", log.LstdFlags|log.Lshortfile)
 	}
 }
 
diff --git a/vendor/github.com/nlopes/slack/stars.go b/vendor/github.com/nlopes/slack/stars.go
index cc12e6ec..cf4a4a11 100644
--- a/vendor/github.com/nlopes/slack/stars.go
+++ b/vendor/github.com/nlopes/slack/stars.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
@@ -37,6 +38,11 @@ func NewStarsParameters() StarsParameters {
 
 // AddStar stars an item in a channel
 func (api *Client) AddStar(channel string, item ItemRef) error {
+	return api.AddStarContext(context.Background(), channel, item)
+}
+
+// AddStarContext stars an item in a channel with a custom context
+func (api *Client) AddStarContext(ctx context.Context, channel string, item ItemRef) error {
 	values := url.Values{
 		"channel": {channel},
 		"token":   {api.config.token},
@@ -51,7 +57,7 @@ func (api *Client) AddStar(channel string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("stars.add", values, response, api.debug); err != nil {
+	if err := post(ctx, "stars.add", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -62,6 +68,11 @@ func (api *Client) AddStar(channel string, item ItemRef) error {
 
 // RemoveStar removes a starred item from a channel
 func (api *Client) RemoveStar(channel string, item ItemRef) error {
+	return api.RemoveStarContext(context.Background(), channel, item)
+}
+
+// RemoveStarContext removes a starred item from a channel with a custom context
+func (api *Client) RemoveStarContext(ctx context.Context, channel string, item ItemRef) error {
 	values := url.Values{
 		"channel": {channel},
 		"token":   {api.config.token},
@@ -76,7 +87,7 @@ func (api *Client) RemoveStar(channel string, item ItemRef) error {
 		values.Set("file_comment", string(item.Comment))
 	}
 	response := &SlackResponse{}
-	if err := post("stars.remove", values, response, api.debug); err != nil {
+	if err := post(ctx, "stars.remove", values, response, api.debug); err != nil {
 		return err
 	}
 	if !response.Ok {
@@ -87,6 +98,11 @@ func (api *Client) RemoveStar(channel string, item ItemRef) error {
 
 // ListStars returns information about the stars a user added
 func (api *Client) ListStars(params StarsParameters) ([]Item, *Paging, error) {
+	return api.ListStarsContext(context.Background(), params)
+}
+
+// ListStarsContext returns information about the stars a user added with a custom context
+func (api *Client) ListStarsContext(ctx context.Context, params StarsParameters) ([]Item, *Paging, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -100,7 +116,7 @@ func (api *Client) ListStars(params StarsParameters) ([]Item, *Paging, error) {
 		values.Add("page", strconv.Itoa(params.Page))
 	}
 	response := &listResponseFull{}
-	err := post("stars.list", values, response, api.debug)
+	err := post(ctx, "stars.list", values, response, api.debug)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -110,7 +126,9 @@ func (api *Client) ListStars(params StarsParameters) ([]Item, *Paging, 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
+// 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 {
@@ -123,7 +141,14 @@ func (api *Client) ListStars(params StarsParameters) ([]Item, *Paging, error) {
 // 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)
+	return api.GetStarredContext(context.Background(), params)
+}
+
+// GetStarredContext returns a list of StarredItem items with a custom context
+//
+// For more details see GetStarred
+func (api *Client) GetStarredContext(ctx context.Context, params StarsParameters) ([]StarredItem, *Paging, error) {
+	items, paging, err := api.ListStarsContext(ctx, params)
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/team.go b/vendor/github.com/nlopes/slack/team.go
index 61b6a0a1..e70ac57e 100644
--- a/vendor/github.com/nlopes/slack/team.go
+++ b/vendor/github.com/nlopes/slack/team.go
@@ -1,14 +1,15 @@
 package slack
 
 import (
+	"context"
 	"errors"
 	"net/url"
 	"strconv"
 )
 
 const (
-	DEFAULT_LOGINS_COUNT   = 100
-	DEFAULT_LOGINS_PAGE    = 1
+	DEFAULT_LOGINS_COUNT = 100
+	DEFAULT_LOGINS_PAGE  = 1
 )
 
 type TeamResponse struct {
@@ -26,11 +27,10 @@ type TeamInfo struct {
 
 type LoginResponse struct {
 	Logins []Login `json:"logins"`
-	Paging         `json:"paging"`
+	Paging `json:"paging"`
 	SlackResponse
 }
 
-
 type Login struct {
 	UserID    string `json:"user_id"`
 	Username  string `json:"username"`
@@ -47,7 +47,6 @@ type Login struct {
 type BillableInfoResponse struct {
 	BillableInfo map[string]BillingActive `json:"billable_info"`
 	SlackResponse
-
 }
 
 type BillingActive struct {
@@ -56,8 +55,8 @@ type BillingActive struct {
 
 // AccessLogParameters contains all the parameters necessary (including the optional ones) for a GetAccessLogs() request
 type AccessLogParameters struct {
-	Count         int
-	Page          int
+	Count int
+	Page  int
 }
 
 // NewAccessLogParameters provides an instance of AccessLogParameters with all the sane default values set
@@ -68,10 +67,9 @@ func NewAccessLogParameters() AccessLogParameters {
 	}
 }
 
-
-func teamRequest(path string, values url.Values, debug bool) (*TeamResponse, error) {
+func teamRequest(ctx context.Context, path string, values url.Values, debug bool) (*TeamResponse, error) {
 	response := &TeamResponse{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -83,9 +81,9 @@ func teamRequest(path string, values url.Values, debug bool) (*TeamResponse, err
 	return response, nil
 }
 
-func billableInfoRequest(path string, values url.Values, debug bool) (map[string]BillingActive, error) {
+func billableInfoRequest(ctx context.Context, path string, values url.Values, debug bool) (map[string]BillingActive, error) {
 	response := &BillableInfoResponse{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -97,9 +95,9 @@ func billableInfoRequest(path string, values url.Values, debug bool) (map[string
 	return response.BillableInfo, nil
 }
 
-func accessLogsRequest(path string, values url.Values, debug bool) (*LoginResponse, error) {
+func accessLogsRequest(ctx context.Context, path string, values url.Values, debug bool) (*LoginResponse, error) {
 	response := &LoginResponse{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -109,14 +107,18 @@ func accessLogsRequest(path string, values url.Values, debug bool) (*LoginRespon
 	return response, nil
 }
 
-
 // GetTeamInfo gets the Team Information of the user
 func (api *Client) GetTeamInfo() (*TeamInfo, error) {
+	return api.GetTeamInfoContext(context.Background())
+}
+
+// GetTeamInfoContext gets the Team Information of the user with a custom context
+func (api *Client) GetTeamInfoContext(ctx context.Context) (*TeamInfo, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 
-	response, err := teamRequest("team.info", values, api.debug)
+	response, err := teamRequest(ctx, "team.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -125,6 +127,11 @@ func (api *Client) GetTeamInfo() (*TeamInfo, error) {
 
 // GetAccessLogs retrieves a page of logins according to the parameters given
 func (api *Client) GetAccessLogs(params AccessLogParameters) ([]Login, *Paging, error) {
+	return api.GetAccessLogsContext(context.Background(), params)
+}
+
+// GetAccessLogsContext retrieves a page of logins according to the parameters given with a custom context
+func (api *Client) GetAccessLogsContext(ctx context.Context, params AccessLogParameters) ([]Login, *Paging, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
@@ -134,7 +141,7 @@ func (api *Client) GetAccessLogs(params AccessLogParameters) ([]Login, *Paging,
 	if params.Page != DEFAULT_LOGINS_PAGE {
 		values.Add("page", strconv.Itoa(params.Page))
 	}
-	response, err := accessLogsRequest("team.accessLogs", values, api.debug)
+	response, err := accessLogsRequest(ctx, "team.accessLogs", values, api.debug)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -142,19 +149,28 @@ func (api *Client) GetAccessLogs(params AccessLogParameters) ([]Login, *Paging,
 }
 
 func (api *Client) GetBillableInfo(user string) (map[string]BillingActive, error) {
+	return api.GetBillableInfoContext(context.Background(), user)
+}
+
+func (api *Client) GetBillableInfoContext(ctx context.Context, user string) (map[string]BillingActive, error) {
 	values := url.Values{
 		"token": {api.config.token},
-		"user": {user},
+		"user":  {user},
 	}
 
-	return billableInfoRequest("team.billableInfo", values, api.debug)
+	return billableInfoRequest(ctx, "team.billableInfo", values, api.debug)
 }
 
 // GetBillableInfoForTeam returns the billing_active status of all users on the team.
 func (api *Client) GetBillableInfoForTeam() (map[string]BillingActive, error) {
+	return api.GetBillableInfoForTeamContext(context.Background())
+}
+
+// GetBillableInfoForTeamContext returns the billing_active status of all users on the team with a custom context
+func (api *Client) GetBillableInfoForTeamContext(ctx context.Context) (map[string]BillingActive, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 
-	return billableInfoRequest("team.billableInfo", values, api.debug)
+	return billableInfoRequest(ctx, "team.billableInfo", values, api.debug)
 }
diff --git a/vendor/github.com/nlopes/slack/usergroups.go b/vendor/github.com/nlopes/slack/usergroups.go
new file mode 100644
index 00000000..de9f9864
--- /dev/null
+++ b/vendor/github.com/nlopes/slack/usergroups.go
@@ -0,0 +1,210 @@
+package slack
+
+import (
+	"context"
+	"errors"
+	"net/url"
+	"strings"
+)
+
+// UserGroup contains all the information of a user group
+type UserGroup struct {
+	ID          string         `json:"id"`
+	TeamID      string         `json:"team_id"`
+	IsUserGroup bool           `json:"is_usergroup"`
+	Name        string         `json:"name"`
+	Description string         `json:"description"`
+	Handle      string         `json:"handle"`
+	IsExternal  bool           `json:"is_external"`
+	DateCreate  JSONTime       `json:"date_create"`
+	DateUpdate  JSONTime       `json:"date_update"`
+	DateDelete  JSONTime       `json:"date_delete"`
+	AutoType    string         `json:"auto_type"`
+	CreatedBy   string         `json:"created_by"`
+	UpdatedBy   string         `json:"updated_by"`
+	DeletedBy   string         `json:"deleted_by"`
+	Prefs       UserGroupPrefs `json:"prefs"`
+	UserCount   int            `json:"user_count"`
+}
+
+// UserGroupPrefs contains default channels and groups (private channels)
+type UserGroupPrefs struct {
+	Channels []string `json:"channels"`
+	Groups   []string `json:"groups"`
+}
+
+type userGroupResponseFull struct {
+	UserGroups []UserGroup `json:"usergroups"`
+	UserGroup  UserGroup   `json:"usergroup"`
+	Users      []string    `json:"users"`
+	SlackResponse
+}
+
+func userGroupRequest(ctx context.Context, path string, values url.Values, debug bool) (*userGroupResponseFull, error) {
+	response := &userGroupResponseFull{}
+	err := post(ctx, path, values, response, debug)
+	if err != nil {
+		return nil, err
+	}
+	if !response.Ok {
+		return nil, errors.New(response.Error)
+	}
+	return response, nil
+}
+
+// CreateUserGroup creates a new user group
+func (api *Client) CreateUserGroup(userGroup UserGroup) (UserGroup, error) {
+	return api.CreateUserGroupContext(context.Background(), userGroup)
+}
+
+// CreateUserGroupContext creates a new user group with a custom context
+func (api *Client) CreateUserGroupContext(ctx context.Context, userGroup UserGroup) (UserGroup, error) {
+	values := url.Values{
+		"token": {api.config.token},
+		"name":  {userGroup.Name},
+	}
+
+	if userGroup.Handle != "" {
+		values["handle"] = []string{userGroup.Handle}
+	}
+
+	if userGroup.Description != "" {
+		values["description"] = []string{userGroup.Description}
+	}
+
+	if len(userGroup.Prefs.Channels) > 0 {
+		values["channels"] = []string{strings.Join(userGroup.Prefs.Channels, ",")}
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.create", values, api.debug)
+	if err != nil {
+		return UserGroup{}, err
+	}
+	return response.UserGroup, nil
+}
+
+// DisableUserGroup disables an existing user group
+func (api *Client) DisableUserGroup(userGroup string) (UserGroup, error) {
+	return api.DisableUserGroupContext(context.Background(), userGroup)
+}
+
+// DisableUserGroupContext disables an existing user group with a custom context
+func (api *Client) DisableUserGroupContext(ctx context.Context, userGroup string) (UserGroup, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"usergroup": {userGroup},
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.disable", values, api.debug)
+	if err != nil {
+		return UserGroup{}, err
+	}
+	return response.UserGroup, nil
+}
+
+// EnableUserGroup enables an existing user group
+func (api *Client) EnableUserGroup(userGroup string) (UserGroup, error) {
+	return api.EnableUserGroupContext(context.Background(), userGroup)
+}
+
+// EnableUserGroupContext enables an existing user group with a custom context
+func (api *Client) EnableUserGroupContext(ctx context.Context, userGroup string) (UserGroup, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"usergroup": {userGroup},
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.enable", values, api.debug)
+	if err != nil {
+		return UserGroup{}, err
+	}
+	return response.UserGroup, nil
+}
+
+// GetUserGroups returns a list of user groups for the team
+func (api *Client) GetUserGroups() ([]UserGroup, error) {
+	return api.GetUserGroupsContext(context.Background())
+}
+
+// GetUserGroupsContext returns a list of user groups for the team with a custom context
+func (api *Client) GetUserGroupsContext(ctx context.Context) ([]UserGroup, error) {
+	values := url.Values{
+		"token": {api.config.token},
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.list", values, api.debug)
+	if err != nil {
+		return nil, err
+	}
+	return response.UserGroups, nil
+}
+
+// UpdateUserGroup will update an existing user group
+func (api *Client) UpdateUserGroup(userGroup UserGroup) (UserGroup, error) {
+	return api.UpdateUserGroupContext(context.Background(), userGroup)
+}
+
+// UpdateUserGroupContext will update an existing user group with a custom context
+func (api *Client) UpdateUserGroupContext(ctx context.Context, userGroup UserGroup) (UserGroup, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"usergroup": {userGroup.ID},
+	}
+
+	if userGroup.Name != "" {
+		values["name"] = []string{userGroup.Name}
+	}
+
+	if userGroup.Handle != "" {
+		values["handle"] = []string{userGroup.Handle}
+	}
+
+	if userGroup.Description != "" {
+		values["description"] = []string{userGroup.Description}
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.update", values, api.debug)
+	if err != nil {
+		return UserGroup{}, err
+	}
+	return response.UserGroup, nil
+}
+
+// GetUserGroupMembers will retrieve the current list of users in a group
+func (api *Client) GetUserGroupMembers(userGroup string) ([]string, error) {
+	return api.GetUserGroupMembersContext(context.Background(), userGroup)
+}
+
+// GetUserGroupMembersContext will retrieve the current list of users in a group with a custom context
+func (api *Client) GetUserGroupMembersContext(ctx context.Context, userGroup string) ([]string, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"usergroup": {userGroup},
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.users.list", values, api.debug)
+	if err != nil {
+		return []string{}, err
+	}
+	return response.Users, nil
+}
+
+// UpdateUserGroupMembers will update the members of an existing user group
+func (api *Client) UpdateUserGroupMembers(userGroup string, members string) (UserGroup, error) {
+	return api.UpdateUserGroupMembersContext(context.Background(), userGroup, members)
+}
+
+// UpdateUserGroupMembersContext will update the members of an existing user group with a custom context
+func (api *Client) UpdateUserGroupMembersContext(ctx context.Context, userGroup string, members string) (UserGroup, error) {
+	values := url.Values{
+		"token":     {api.config.token},
+		"usergroup": {userGroup},
+		"users":     {members},
+	}
+
+	response, err := userGroupRequest(ctx, "usergroups.users.update", values, api.debug)
+	if err != nil {
+		return UserGroup{}, err
+	}
+	return response.UserGroup, nil
+}
diff --git a/vendor/github.com/nlopes/slack/users.go b/vendor/github.com/nlopes/slack/users.go
index c71f4ee2..0aa95570 100644
--- a/vendor/github.com/nlopes/slack/users.go
+++ b/vendor/github.com/nlopes/slack/users.go
@@ -1,10 +1,18 @@
 package slack
 
 import (
+	"context"
+	"encoding/json"
 	"errors"
 	"net/url"
 )
 
+const (
+	DEFAULT_USER_PHOTO_CROP_X = -1
+	DEFAULT_USER_PHOTO_CROP_Y = -1
+	DEFAULT_USER_PHOTO_CROP_W = -1
+)
+
 // UserProfile contains all the information details of a given user
 type UserProfile struct {
 	FirstName          string `json:"first_name"`
@@ -23,6 +31,8 @@ type UserProfile struct {
 	Title              string `json:"title"`
 	BotID              string `json:"bot_id,omitempty"`
 	ApiAppID           string `json:"api_app_id,omitempty"`
+	StatusText         string `json:"status_text,omitempty"`
+	StatusEmoji        string `json:"status_emoji,omitempty"`
 }
 
 // User contains all the information of a user
@@ -97,9 +107,23 @@ type userResponseFull struct {
 	SlackResponse
 }
 
-func userRequest(path string, values url.Values, debug bool) (*userResponseFull, error) {
+type UserSetPhotoParams struct {
+	CropX int
+	CropY int
+	CropW int
+}
+
+func NewUserSetPhotoParams() UserSetPhotoParams {
+	return UserSetPhotoParams{
+		CropX: DEFAULT_USER_PHOTO_CROP_X,
+		CropY: DEFAULT_USER_PHOTO_CROP_Y,
+		CropW: DEFAULT_USER_PHOTO_CROP_W,
+	}
+}
+
+func userRequest(ctx context.Context, path string, values url.Values, debug bool) (*userResponseFull, error) {
 	response := &userResponseFull{}
-	err := post(path, values, response, debug)
+	err := post(ctx, path, values, response, debug)
 	if err != nil {
 		return nil, err
 	}
@@ -111,11 +135,16 @@ func userRequest(path string, values url.Values, debug bool) (*userResponseFull,
 
 // GetUserPresence will retrieve the current presence status of given user.
 func (api *Client) GetUserPresence(user string) (*UserPresence, error) {
+	return api.GetUserPresenceContext(context.Background(), user)
+}
+
+// GetUserPresenceContext will retrieve the current presence status of given user with a custom context.
+func (api *Client) GetUserPresenceContext(ctx context.Context, user string) (*UserPresence, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"user":  {user},
 	}
-	response, err := userRequest("users.getPresence", values, api.debug)
+	response, err := userRequest(ctx, "users.getPresence", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -124,11 +153,16 @@ func (api *Client) GetUserPresence(user string) (*UserPresence, error) {
 
 // GetUserInfo will retrieve the complete user information
 func (api *Client) GetUserInfo(user string) (*User, error) {
+	return api.GetUserInfoContext(context.Background(), user)
+}
+
+// GetUserInfoContext will retrieve the complete user information with a custom context
+func (api *Client) GetUserInfoContext(ctx context.Context, user string) (*User, error) {
 	values := url.Values{
 		"token": {api.config.token},
 		"user":  {user},
 	}
-	response, err := userRequest("users.info", values, api.debug)
+	response, err := userRequest(ctx, "users.info", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -137,11 +171,16 @@ func (api *Client) GetUserInfo(user string) (*User, error) {
 
 // GetUsers returns the list of users (with their detailed information)
 func (api *Client) GetUsers() ([]User, error) {
+	return api.GetUsersContext(context.Background())
+}
+
+// GetUsersContext returns the list of users (with their detailed information) with a custom context
+func (api *Client) GetUsersContext(ctx context.Context) ([]User, error) {
 	values := url.Values{
 		"token":    {api.config.token},
 		"presence": {"1"},
 	}
-	response, err := userRequest("users.list", values, api.debug)
+	response, err := userRequest(ctx, "users.list", values, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -150,10 +189,15 @@ func (api *Client) GetUsers() ([]User, error) {
 
 // SetUserAsActive marks the currently authenticated user as active
 func (api *Client) SetUserAsActive() error {
+	return api.SetUserAsActiveContext(context.Background())
+}
+
+// SetUserAsActiveContext marks the currently authenticated user as active with a custom context
+func (api *Client) SetUserAsActiveContext(ctx context.Context) error {
 	values := url.Values{
 		"token": {api.config.token},
 	}
-	_, err := userRequest("users.setActive", values, api.debug)
+	_, err := userRequest(ctx, "users.setActive", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -162,11 +206,16 @@ func (api *Client) SetUserAsActive() error {
 
 // SetUserPresence changes the currently authenticated user presence
 func (api *Client) SetUserPresence(presence string) error {
+	return api.SetUserPresenceContext(context.Background(), presence)
+}
+
+// SetUserPresenceContext changes the currently authenticated user presence with a custom context
+func (api *Client) SetUserPresenceContext(ctx context.Context, presence string) error {
 	values := url.Values{
 		"token":    {api.config.token},
 		"presence": {presence},
 	}
-	_, err := userRequest("users.setPresence", values, api.debug)
+	_, err := userRequest(ctx, "users.setPresence", values, api.debug)
 	if err != nil {
 		return err
 	}
@@ -176,11 +225,16 @@ func (api *Client) SetUserPresence(presence string) error {
 
 // GetUserIdentity will retrieve user info available per identity scopes
 func (api *Client) GetUserIdentity() (*UserIdentityResponse, error) {
+	return api.GetUserIdentityContext(context.Background())
+}
+
+// GetUserIdentityContext will retrieve user info available per identity scopes with a custom context
+func (api *Client) GetUserIdentityContext(ctx context.Context) (*UserIdentityResponse, error) {
 	values := url.Values{
 		"token": {api.config.token},
 	}
 	response := &UserIdentityResponse{}
-	err := post("users.identity", values, response, api.debug)
+	err := post(ctx, "users.identity", values, response, api.debug)
 	if err != nil {
 		return nil, err
 	}
@@ -189,3 +243,120 @@ func (api *Client) GetUserIdentity() (*UserIdentityResponse, error) {
 	}
 	return response, nil
 }
+
+// SetUserPhoto changes the currently authenticated user's profile image
+func (api *Client) SetUserPhoto(ctx context.Context, image string, params UserSetPhotoParams) error {
+	return api.SetUserPhoto(context.Background(), image, params)
+}
+
+// SetUserPhotoContext changes the currently authenticated user's profile image using a custom context
+func (api *Client) SetUserPhotoContext(ctx context.Context, image string, params UserSetPhotoParams) error {
+	response := &SlackResponse{}
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	if params.CropX != DEFAULT_USER_PHOTO_CROP_X {
+		values.Add("crop_x", string(params.CropX))
+	}
+	if params.CropY != DEFAULT_USER_PHOTO_CROP_Y {
+		values.Add("crop_y", string(params.CropY))
+	}
+	if params.CropW != DEFAULT_USER_PHOTO_CROP_W {
+		values.Add("crop_w", string(params.CropW))
+	}
+	err := postLocalWithMultipartResponse(ctx, "users.setPhoto", image, "image", values, response, api.debug)
+	if err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// DeleteUserPhoto deletes the current authenticated user's profile image
+func (api *Client) DeleteUserPhoto() error {
+	return api.DeleteUserPhotoContext(context.Background())
+}
+
+// DeleteUserPhotoContext deletes the current authenticated user's profile image with a custom context
+func (api *Client) DeleteUserPhotoContext(ctx context.Context) error {
+	response := &SlackResponse{}
+	values := url.Values{
+		"token": {api.config.token},
+	}
+	err := post(ctx, "users.deletePhoto", values, response, api.debug)
+	if err != nil {
+		return err
+	}
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+	return nil
+}
+
+// SetUserCustomStatus will set a custom status and emoji for the currently
+// authenticated user. If statusEmoji is "" and statusText is not, the Slack API
+// will automatically set it to ":speech_balloon:". Otherwise, if both are ""
+// the Slack API will unset the custom status/emoji.
+func (api *Client) SetUserCustomStatus(statusText, statusEmoji string) error {
+	return api.SetUserCustomStatusContext(context.Background(), statusText, statusEmoji)
+}
+
+// SetUserCustomStatusContext will set a custom status and emoji for the currently authenticated user with a custom context
+//
+// For more information see SetUserCustomStatus
+func (api *Client) SetUserCustomStatusContext(ctx context.Context, statusText, statusEmoji string) error {
+	// XXX(theckman): this anonymous struct is for making requests to the Slack
+	// API for setting and unsetting a User's Custom Status/Emoji. To change
+	// these values we must provide a JSON document as the profile POST field.
+	//
+	// We use an anonymous struct over UserProfile because to unset the values
+	// on the User's profile we cannot use the `json:"omitempty"` tag. This is
+	// because an empty string ("") is what's used to unset the values. Check
+	// out the API docs for more details:
+	//
+	// - https://api.slack.com/docs/presence-and-status#custom_status
+	profile, err := json.Marshal(
+		&struct {
+			StatusText  string `json:"status_text"`
+			StatusEmoji string `json:"status_emoji"`
+		}{
+			StatusText:  statusText,
+			StatusEmoji: statusEmoji,
+		},
+	)
+
+	if err != nil {
+		return err
+	}
+
+	values := url.Values{
+		"token":   {api.config.token},
+		"profile": {string(profile)},
+	}
+
+	response := &userResponseFull{}
+
+	if err = post(ctx, "users.profile.set", values, response, api.debug); err != nil {
+		return err
+	}
+
+	if !response.Ok {
+		return errors.New(response.Error)
+	}
+
+	return nil
+}
+
+// UnsetUserCustomStatus removes the custom status message for the currently
+// authenticated user. This is a convenience method that wraps (*Client).SetUserCustomStatus().
+func (api *Client) UnsetUserCustomStatus() error {
+	return api.UnsetUserCustomStatusContext(context.Background())
+}
+
+// UnsetUserCustomStatusContext removes the custom status message for the currently authenticated user
+// with a custom context. This is a convenience method that wraps (*Client).SetUserCustomStatus().
+func (api *Client) UnsetUserCustomStatusContext(ctx context.Context) error {
+	return api.SetUserCustomStatusContext(ctx, "", "")
+}
diff --git a/vendor/github.com/nlopes/slack/websocket.go b/vendor/github.com/nlopes/slack/websocket.go
index 6eb09263..f3c9cbd8 100644
--- a/vendor/github.com/nlopes/slack/websocket.go
+++ b/vendor/github.com/nlopes/slack/websocket.go
@@ -17,7 +17,7 @@ const (
 // RTM represents a managed websocket connection. It also supports
 // all the methods of the `Client` type.
 //
-// Create this element with Client's NewRTM().
+// Create this element with Client's NewRTM() or NewRTMWithOptions(*RTMOptions)
 type RTM struct {
 	idGen IDGenerator
 	pings map[int]time.Time
@@ -38,23 +38,23 @@ type RTM struct {
 
 	// UserDetails upon connection
 	info *Info
+
+	// useRTMStart should be set to true if you want to use
+	// rtm.start to connect to Slack, otherwise it will use
+	// rtm.connect
+	useRTMStart bool
 }
 
-// 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),
-	}
+// RTMOptions allows configuration of various options available for RTM messaging
+//
+// This structure will evolve in time so please make sure you are always using the
+// named keys for every entry available as per Go 1 compatibility promise adding fields
+// to this structure should not be considered a breaking change.
+type RTMOptions struct {
+	// UseRTMStart set to true in order to use rtm.start or false to use rtm.connect
+	// As of 11th July 2017 you should prefer setting this to false, see:
+	// https://api.slack.com/changelog/2017-04-start-using-rtm-connect-and-stop-using-rtm-start
+	UseRTMStart bool
 }
 
 // Disconnect and wait, blocking until a successful disconnection.
diff --git a/vendor/github.com/nlopes/slack/websocket_managed_conn.go b/vendor/github.com/nlopes/slack/websocket_managed_conn.go
index 65bb7299..762b8f11 100644
--- a/vendor/github.com/nlopes/slack/websocket_managed_conn.go
+++ b/vendor/github.com/nlopes/slack/websocket_managed_conn.go
@@ -29,7 +29,7 @@ func (rtm *RTM) ManageConnection() {
 		connectionCount++
 		// start trying to connect
 		// the returned err is already passed onto the IncomingEvents channel
-		info, conn, err := rtm.connect(connectionCount)
+		info, conn, err := rtm.connect(connectionCount, rtm.useRTMStart)
 		// if err != nil then the connection is sucessful - otherwise it is
 		// fatal
 		if err != nil {
@@ -64,7 +64,9 @@ func (rtm *RTM) ManageConnection() {
 // 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) {
+// If useRTMStart is false then it uses rtm.connect to create the connection,
+// otherwise it uses rtm.start.
+func (rtm *RTM) connect(connectionCount int, useRTMStart bool) (*Info, *websocket.Conn, error) {
 	// used to provide exponential backoff wait time with jitter before trying
 	// to connect to slack again
 	boff := &backoff{
@@ -81,7 +83,7 @@ func (rtm *RTM) connect(connectionCount int) (*Info, *websocket.Conn, error) {
 			ConnectionCount: connectionCount,
 		}}
 		// attempt to start the connection
-		info, conn, err := rtm.startRTMAndDial()
+		info, conn, err := rtm.startRTMAndDial(useRTMStart)
 		if err == nil {
 			return info, conn, nil
 		}
@@ -105,10 +107,19 @@ func (rtm *RTM) connect(connectionCount int) (*Info, *websocket.Conn, error) {
 	}
 }
 
-// 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()
+// startRTMAndDial attempts to connect to the slack websocket. If useRTMStart is true,
+// then it returns the  full information returned by the "rtm.start" method on the
+// slack API. Else it uses the "rtm.connect" method to connect
+func (rtm *RTM) startRTMAndDial(useRTMStart bool) (*Info, *websocket.Conn, error) {
+	var info *Info
+	var url string
+	var err error
+
+	if useRTMStart {
+		info, url, err = rtm.StartRTM()
+	} else {
+		info, url, err = rtm.ConnectRTM()
+	}
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/vendor/github.com/nlopes/slack/websocket_misc.go b/vendor/github.com/nlopes/slack/websocket_misc.go
index 6c2c6abf..ad283ea1 100644
--- a/vendor/github.com/nlopes/slack/websocket_misc.go
+++ b/vendor/github.com/nlopes/slack/websocket_misc.go
@@ -76,8 +76,12 @@ type UserChangeEvent struct {
 
 // EmojiChangedEvent represents the emoji changed event
 type EmojiChangedEvent struct {
-	Type           string `json:"type"`
-	EventTimestamp string `json:"event_ts"`
+	Type           string   `json:"type"`
+	SubType        string   `json:"subtype"`
+	Name           string   `json:"name"`
+	Names          []string `json:"names"`
+	Value          string   `json:"value"` 
+	EventTimestamp string   `json:"event_ts"`
 }
 
 // CommandsChangedEvent represents the commands changed event
diff --git a/vendor/manifest b/vendor/manifest
index 4d8bbd2b..d311a3ab 100644
--- a/vendor/manifest
+++ b/vendor/manifest
@@ -396,7 +396,7 @@
 			"importpath": "github.com/nlopes/slack",
 			"repository": "https://github.com/nlopes/slack",
 			"vcs": "git",
-			"revision": "6519657c021b7add19c4ef48220140cca0b1657b",
+			"revision": "ca8436d76f805ec1e682eaae2de3c3a9bc894b0f",
 			"branch": "master",
 			"notests": true
 		},