Switch back go upstream bwmarrin/discordgo

Commit https://github.com/bwmarrin/discordgo/commit/ffa9956c9b41e8e2a10c26a254389854e016b006 got merged in.

19 files changed, 998 insertions, 305 deletions

diff --git a/vendor/github.com/gorilla/websocket/.gitignore b/vendor/github.com/gorilla/websocket/.gitignore
index ac710204..cd3fcd1e 100644
--- a/vendor/github.com/gorilla/websocket/.gitignore
+++ b/vendor/github.com/gorilla/websocket/.gitignore
@@ -22,4 +22,4 @@ _testmain.go
 *.exe
 
 .idea/
-*.iml
\ No newline at end of file
+*.iml
diff --git a/vendor/github.com/gorilla/websocket/.travis.yml b/vendor/github.com/gorilla/websocket/.travis.yml
index 3d8d29cf..a49db51c 100644
--- a/vendor/github.com/gorilla/websocket/.travis.yml
+++ b/vendor/github.com/gorilla/websocket/.travis.yml
@@ -3,11 +3,11 @@ sudo: false
 
 matrix:
   include:
-    - go: 1.4
-    - go: 1.5
-    - go: 1.6
-    - go: 1.7
-    - go: 1.8
+    - go: 1.7.x
+    - go: 1.8.x
+    - go: 1.9.x
+    - go: 1.10.x
+    - go: 1.11.x
     - go: tip
   allow_failures:
     - go: tip
diff --git a/vendor/github.com/gorilla/websocket/AUTHORS b/vendor/github.com/gorilla/websocket/AUTHORS
index b003eca0..1931f400 100644
--- a/vendor/github.com/gorilla/websocket/AUTHORS
+++ b/vendor/github.com/gorilla/websocket/AUTHORS
@@ -4,5 +4,6 @@
 # Please keep the list sorted.
 
 Gary Burd <gary@beagledreams.com>
+Google LLC (https://opensource.google.com/)
 Joachim Bauch <mail@joachim-bauch.de>
 
diff --git a/vendor/github.com/gorilla/websocket/README.md b/vendor/github.com/gorilla/websocket/README.md
index 33c3d2be..20e391f8 100644
--- a/vendor/github.com/gorilla/websocket/README.md
+++ b/vendor/github.com/gorilla/websocket/README.md
@@ -51,7 +51,7 @@ subdirectory](https://github.com/gorilla/websocket/tree/master/examples/autobahn
 <tr><td>Write message using io.WriteCloser</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.NextWriter">Yes</a></td><td>No, see note 3</td></tr>
 </table>
 
-Notes: 
+Notes:
 
 1. Large messages are fragmented in [Chrome's new WebSocket implementation](http://www.ietf.org/mail-archive/web/hybi/current/msg10503.html).
 2. The application can get the type of a received data message by implementing
diff --git a/vendor/github.com/gorilla/websocket/client.go b/vendor/github.com/gorilla/websocket/client.go
index 43a87c75..2e32fd50 100644
--- a/vendor/github.com/gorilla/websocket/client.go
+++ b/vendor/github.com/gorilla/websocket/client.go
@@ -5,15 +5,15 @@
 package websocket
 
 import (
-	"bufio"
 	"bytes"
+	"context"
 	"crypto/tls"
-	"encoding/base64"
 	"errors"
 	"io"
 	"io/ioutil"
 	"net"
 	"net/http"
+	"net/http/httptrace"
 	"net/url"
 	"strings"
 	"time"
@@ -53,6 +53,10 @@ type Dialer struct {
 	// NetDial is nil, net.Dial is used.
 	NetDial func(network, addr string) (net.Conn, error)
 
+	// NetDialContext specifies the dial function for creating TCP connections. If
+	// NetDialContext is nil, net.DialContext is used.
+	NetDialContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
 	// Proxy specifies a function to return a proxy for a given
 	// Request. If the function returns a non-nil error, the
 	// request is aborted with the provided error.
@@ -71,6 +75,17 @@ type Dialer struct {
 	// do not limit the size of the messages that can be sent or received.
 	ReadBufferSize, WriteBufferSize int
 
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
 	// Subprotocols specifies the client's requested subprotocols.
 	Subprotocols []string
 
@@ -86,52 +101,13 @@ type Dialer struct {
 	Jar http.CookieJar
 }
 
-var errMalformedURL = errors.New("malformed ws or wss URL")
-
-// parseURL parses the URL.
-//
-// This function is a replacement for the standard library url.Parse function.
-// In Go 1.4 and earlier, url.Parse loses information from the path.
-func parseURL(s string) (*url.URL, error) {
-	// From the RFC:
-	//
-	// ws-URI = "ws:" "//" host [ ":" port ] path [ "?" query ]
-	// wss-URI = "wss:" "//" host [ ":" port ] path [ "?" query ]
-	var u url.URL
-	switch {
-	case strings.HasPrefix(s, "ws://"):
-		u.Scheme = "ws"
-		s = s[len("ws://"):]
-	case strings.HasPrefix(s, "wss://"):
-		u.Scheme = "wss"
-		s = s[len("wss://"):]
-	default:
-		return nil, errMalformedURL
-	}
-
-	if i := strings.Index(s, "?"); i >= 0 {
-		u.RawQuery = s[i+1:]
-		s = s[:i]
-	}
-
-	if i := strings.Index(s, "/"); i >= 0 {
-		u.Opaque = s[i:]
-		s = s[:i]
-	} else {
-		u.Opaque = "/"
-	}
-
-	u.Host = s
-
-	if strings.Contains(u.Host, "@") {
-		// Don't bother parsing user information because user information is
-		// not allowed in websocket URIs.
-		return nil, errMalformedURL
-	}
-
-	return &u, nil
+// Dial creates a new client connection by calling DialContext with a background context.
+func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	return d.DialContext(context.Background(), urlStr, requestHeader)
 }
 
+var errMalformedURL = errors.New("malformed ws or wss URL")
+
 func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
 	hostPort = u.Host
 	hostNoPort = u.Host
@@ -150,26 +126,29 @@ func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
 	return hostPort, hostNoPort
 }
 
-// DefaultDialer is a dialer with all fields set to the default zero values.
+// DefaultDialer is a dialer with all fields set to the default values.
 var DefaultDialer = &Dialer{
-	Proxy: http.ProxyFromEnvironment,
+	Proxy:            http.ProxyFromEnvironment,
+	HandshakeTimeout: 45 * time.Second,
 }
 
-// Dial creates a new client connection. Use requestHeader to specify the
+// nilDialer is dialer to use when receiver is nil.
+var nilDialer = *DefaultDialer
+
+// DialContext creates a new client connection. Use requestHeader to specify the
 // origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies (Cookie).
 // Use the response.Header to get the selected subprotocol
 // (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
 //
+// The context will be used in the request and in the Dialer
+//
 // If the WebSocket handshake fails, ErrBadHandshake is returned along with a
 // non-nil *http.Response so that callers can handle redirects, authentication,
 // etcetera. The response body may not contain the entire response and does not
 // need to be closed by the application.
-func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
-
+func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
 	if d == nil {
-		d = &Dialer{
-			Proxy: http.ProxyFromEnvironment,
-		}
+		d = &nilDialer
 	}
 
 	challengeKey, err := generateChallengeKey()
@@ -177,7 +156,7 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		return nil, nil, err
 	}
 
-	u, err := parseURL(urlStr)
+	u, err := url.Parse(urlStr)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -205,6 +184,7 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		Header:     make(http.Header),
 		Host:       u.Host,
 	}
+	req = req.WithContext(ctx)
 
 	// Set the cookies present in the cookie jar of the dialer
 	if d.Jar != nil {
@@ -237,45 +217,83 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 			k == "Sec-Websocket-Extensions" ||
 			(k == "Sec-Websocket-Protocol" && len(d.Subprotocols) > 0):
 			return nil, nil, errors.New("websocket: duplicate header not allowed: " + k)
+		case k == "Sec-Websocket-Protocol":
+			req.Header["Sec-WebSocket-Protocol"] = vs
 		default:
 			req.Header[k] = vs
 		}
 	}
 
 	if d.EnableCompression {
-		req.Header.Set("Sec-Websocket-Extensions", "permessage-deflate; server_no_context_takeover; client_no_context_takeover")
+		req.Header["Sec-WebSocket-Extensions"] = []string{"permessage-deflate; server_no_context_takeover; client_no_context_takeover"}
 	}
 
-	hostPort, hostNoPort := hostPortNoPort(u)
-
-	var proxyURL *url.URL
-	// Check wether the proxy method has been configured
-	if d.Proxy != nil {
-		proxyURL, err = d.Proxy(req)
-	}
-	if err != nil {
-		return nil, nil, err
+	if d.HandshakeTimeout != 0 {
+		var cancel func()
+		ctx, cancel = context.WithTimeout(ctx, d.HandshakeTimeout)
+		defer cancel()
 	}
 
-	var targetHostPort string
-	if proxyURL != nil {
-		targetHostPort, _ = hostPortNoPort(proxyURL)
+	// Get network dial function.
+	var netDial func(network, add string) (net.Conn, error)
+
+	if d.NetDialContext != nil {
+		netDial = func(network, addr string) (net.Conn, error) {
+			return d.NetDialContext(ctx, network, addr)
+		}
+	} else if d.NetDial != nil {
+		netDial = d.NetDial
 	} else {
-		targetHostPort = hostPort
+		netDialer := &net.Dialer{}
+		netDial = func(network, addr string) (net.Conn, error) {
+			return netDialer.DialContext(ctx, network, addr)
+		}
 	}
 
-	var deadline time.Time
-	if d.HandshakeTimeout != 0 {
-		deadline = time.Now().Add(d.HandshakeTimeout)
+	// If needed, wrap the dial function to set the connection deadline.
+	if deadline, ok := ctx.Deadline(); ok {
+		forwardDial := netDial
+		netDial = func(network, addr string) (net.Conn, error) {
+			c, err := forwardDial(network, addr)
+			if err != nil {
+				return nil, err
+			}
+			err = c.SetDeadline(deadline)
+			if err != nil {
+				c.Close()
+				return nil, err
+			}
+			return c, nil
+		}
 	}
 
-	netDial := d.NetDial
-	if netDial == nil {
-		netDialer := &net.Dialer{Deadline: deadline}
-		netDial = netDialer.Dial
+	// If needed, wrap the dial function to connect through a proxy.
+	if d.Proxy != nil {
+		proxyURL, err := d.Proxy(req)
+		if err != nil {
+			return nil, nil, err
+		}
+		if proxyURL != nil {
+			dialer, err := proxy_FromURL(proxyURL, netDialerFunc(netDial))
+			if err != nil {
+				return nil, nil, err
+			}
+			netDial = dialer.Dial
+		}
+	}
+
+	hostPort, hostNoPort := hostPortNoPort(u)
+	trace := httptrace.ContextClientTrace(ctx)
+	if trace != nil && trace.GetConn != nil {
+		trace.GetConn(hostPort)
 	}
 
-	netConn, err := netDial("tcp", targetHostPort)
+	netConn, err := netDial("tcp", hostPort)
+	if trace != nil && trace.GotConn != nil {
+		trace.GotConn(httptrace.GotConnInfo{
+			Conn: netConn,
+		})
+	}
 	if err != nil {
 		return nil, nil, err
 	}
@@ -286,42 +304,6 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 	}()
 
-	if err := netConn.SetDeadline(deadline); err != nil {
-		return nil, nil, err
-	}
-
-	if proxyURL != nil {
-		connectHeader := make(http.Header)
-		if user := proxyURL.User; user != nil {
-			proxyUser := user.Username()
-			if proxyPassword, passwordSet := user.Password(); passwordSet {
-				credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
-				connectHeader.Set("Proxy-Authorization", "Basic "+credential)
-			}
-		}
-		connectReq := &http.Request{
-			Method: "CONNECT",
-			URL:    &url.URL{Opaque: hostPort},
-			Host:   hostPort,
-			Header: connectHeader,
-		}
-
-		connectReq.Write(netConn)
-
-		// Read response.
-		// Okay to use and discard buffered reader here, because
-		// TLS server will not speak until spoken to.
-		br := bufio.NewReader(netConn)
-		resp, err := http.ReadResponse(br, connectReq)
-		if err != nil {
-			return nil, nil, err
-		}
-		if resp.StatusCode != 200 {
-			f := strings.SplitN(resp.Status, " ", 2)
-			return nil, nil, errors.New(f[1])
-		}
-	}
-
 	if u.Scheme == "https" {
 		cfg := cloneTLSConfig(d.TLSClientConfig)
 		if cfg.ServerName == "" {
@@ -329,22 +311,31 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 		tlsConn := tls.Client(netConn, cfg)
 		netConn = tlsConn
-		if err := tlsConn.Handshake(); err != nil {
-			return nil, nil, err
+
+		var err error
+		if trace != nil {
+			err = doHandshakeWithTrace(trace, tlsConn, cfg)
+		} else {
+			err = doHandshake(tlsConn, cfg)
 		}
-		if !cfg.InsecureSkipVerify {
-			if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
-				return nil, nil, err
-			}
+
+		if err != nil {
+			return nil, nil, err
 		}
 	}
 
-	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize)
+	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize, d.WriteBufferPool, nil, nil)
 
 	if err := req.Write(netConn); err != nil {
 		return nil, nil, err
 	}
 
+	if trace != nil && trace.GotFirstResponseByte != nil {
+		if peek, err := conn.br.Peek(1); err == nil && len(peek) == 1 {
+			trace.GotFirstResponseByte()
+		}
+	}
+
 	resp, err := http.ReadResponse(conn.br, req)
 	if err != nil {
 		return nil, nil, err
@@ -390,3 +381,15 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	netConn = nil // to avoid close in defer.
 	return conn, resp, nil
 }
+
+func doHandshake(tlsConn *tls.Conn, cfg *tls.Config) error {
+	if err := tlsConn.Handshake(); err != nil {
+		return err
+	}
+	if !cfg.InsecureSkipVerify {
+		if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/gorilla/websocket/conn.go b/vendor/github.com/gorilla/websocket/conn.go
index 97e1dbac..d2a21c14 100644
--- a/vendor/github.com/gorilla/websocket/conn.go
+++ b/vendor/github.com/gorilla/websocket/conn.go
@@ -76,7 +76,7 @@ const (
 	// is UTF-8 encoded text.
 	PingMessage = 9
 
-	// PongMessage denotes a ping control message. The optional message payload
+	// PongMessage denotes a pong control message. The optional message payload
 	// is UTF-8 encoded text.
 	PongMessage = 10
 )
@@ -100,9 +100,8 @@ func (e *netError) Error() string   { return e.msg }
 func (e *netError) Temporary() bool { return e.temporary }
 func (e *netError) Timeout() bool   { return e.timeout }
 
-// CloseError represents close frame.
+// CloseError represents a close message.
 type CloseError struct {
-
 	// Code is defined in RFC 6455, section 11.7.
 	Code int
 
@@ -224,6 +223,20 @@ func isValidReceivedCloseCode(code int) bool {
 	return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
 }
 
+// BufferPool represents a pool of buffers. The *sync.Pool type satisfies this
+// interface.  The type of the value stored in a pool is not specified.
+type BufferPool interface {
+	// Get gets a value from the pool or returns nil if the pool is empty.
+	Get() interface{}
+	// Put adds a value to the pool.
+	Put(interface{})
+}
+
+// writePoolData is the type added to the write buffer pool. This wrapper is
+// used to prevent applications from peeking at and depending on the values
+// added to the pool.
+type writePoolData struct{ buf []byte }
+
 // The Conn type represents a WebSocket connection.
 type Conn struct {
 	conn        net.Conn
@@ -233,6 +246,8 @@ type Conn struct {
 	// Write fields
 	mu            chan bool // used as mutex to protect write to conn
 	writeBuf      []byte    // frame is constructed in this buffer.
+	writePool     BufferPool
+	writeBufSize  int
 	writeDeadline time.Time
 	writer        io.WriteCloser // the current writer returned to the application
 	isWriting     bool           // for best-effort concurrent write detection
@@ -264,64 +279,29 @@ type Conn struct {
 	newDecompressionReader func(io.Reader) io.ReadCloser
 }
 
-func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
-	return newConnBRW(conn, isServer, readBufferSize, writeBufferSize, nil)
-}
-
-type writeHook struct {
-	p []byte
-}
-
-func (wh *writeHook) Write(p []byte) (int, error) {
-	wh.p = p
-	return len(p), nil
-}
-
-func newConnBRW(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, brw *bufio.ReadWriter) *Conn {
-	mu := make(chan bool, 1)
-	mu <- true
+func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, writeBufferPool BufferPool, br *bufio.Reader, writeBuf []byte) *Conn {
 
-	var br *bufio.Reader
-	if readBufferSize == 0 && brw != nil && brw.Reader != nil {
-		// Reuse the supplied bufio.Reader if the buffer has a useful size.
-		// This code assumes that peek on a reader returns
-		// bufio.Reader.buf[:0].
-		brw.Reader.Reset(conn)
-		if p, err := brw.Reader.Peek(0); err == nil && cap(p) >= 256 {
-			br = brw.Reader
-		}
-	}
 	if br == nil {
 		if readBufferSize == 0 {
 			readBufferSize = defaultReadBufferSize
-		}
-		if readBufferSize < maxControlFramePayloadSize {
+		} else if readBufferSize < maxControlFramePayloadSize {
+			// must be large enough for control frame
 			readBufferSize = maxControlFramePayloadSize
 		}
 		br = bufio.NewReaderSize(conn, readBufferSize)
 	}
 
-	var writeBuf []byte
-	if writeBufferSize == 0 && brw != nil && brw.Writer != nil {
-		// Use the bufio.Writer's buffer if the buffer has a useful size. This
-		// code assumes that bufio.Writer.buf[:1] is passed to the
-		// bufio.Writer's underlying writer.
-		var wh writeHook
-		brw.Writer.Reset(&wh)
-		brw.Writer.WriteByte(0)
-		brw.Flush()
-		if cap(wh.p) >= maxFrameHeaderSize+256 {
-			writeBuf = wh.p[:cap(wh.p)]
-		}
+	if writeBufferSize <= 0 {
+		writeBufferSize = defaultWriteBufferSize
 	}
+	writeBufferSize += maxFrameHeaderSize
 
-	if writeBuf == nil {
-		if writeBufferSize == 0 {
-			writeBufferSize = defaultWriteBufferSize
-		}
-		writeBuf = make([]byte, writeBufferSize+maxFrameHeaderSize)
+	if writeBuf == nil && writeBufferPool == nil {
+		writeBuf = make([]byte, writeBufferSize)
 	}
 
+	mu := make(chan bool, 1)
+	mu <- true
 	c := &Conn{
 		isServer:               isServer,
 		br:                     br,
@@ -329,6 +309,8 @@ func newConnBRW(conn net.Conn, isServer bool, readBufferSize, writeBufferSize in
 		mu:                     mu,
 		readFinal:              true,
 		writeBuf:               writeBuf,
+		writePool:              writeBufferPool,
+		writeBufSize:           writeBufferSize,
 		enableWriteCompression: true,
 		compressionLevel:       defaultCompressionLevel,
 	}
@@ -343,7 +325,8 @@ func (c *Conn) Subprotocol() string {
 	return c.subprotocol
 }
 
-// Close closes the underlying network connection without sending or waiting for a close frame.
+// Close closes the underlying network connection without sending or waiting
+// for a close message.
 func (c *Conn) Close() error {
 	return c.conn.Close()
 }
@@ -370,7 +353,16 @@ func (c *Conn) writeFatal(err error) error {
 	return err
 }
 
-func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
+func (c *Conn) read(n int) ([]byte, error) {
+	p, err := c.br.Peek(n)
+	if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	c.br.Discard(len(p))
+	return p, err
+}
+
+func (c *Conn) write(frameType int, deadline time.Time, buf0, buf1 []byte) error {
 	<-c.mu
 	defer func() { c.mu <- true }()
 
@@ -382,15 +374,14 @@ func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
 	}
 
 	c.conn.SetWriteDeadline(deadline)
-	for _, buf := range bufs {
-		if len(buf) > 0 {
-			_, err := c.conn.Write(buf)
-			if err != nil {
-				return c.writeFatal(err)
-			}
-		}
+	if len(buf1) == 0 {
+		_, err = c.conn.Write(buf0)
+	} else {
+		err = c.writeBufs(buf0, buf1)
+	}
+	if err != nil {
+		return c.writeFatal(err)
 	}
-
 	if frameType == CloseMessage {
 		c.writeFatal(ErrCloseSent)
 	}
@@ -476,7 +467,19 @@ func (c *Conn) prepWrite(messageType int) error {
 	c.writeErrMu.Lock()
 	err := c.writeErr
 	c.writeErrMu.Unlock()
-	return err
+	if err != nil {
+		return err
+	}
+
+	if c.writeBuf == nil {
+		wpd, ok := c.writePool.Get().(writePoolData)
+		if ok {
+			c.writeBuf = wpd.buf
+		} else {
+			c.writeBuf = make([]byte, c.writeBufSize)
+		}
+	}
+	return nil
 }
 
 // NextWriter returns a writer for the next message to send. The writer's Close
@@ -484,6 +487,9 @@ func (c *Conn) prepWrite(messageType int) error {
 //
 // There can be at most one open writer on a connection. NextWriter closes the
 // previous writer if the application has not already done so.
+//
+// All message types (TextMessage, BinaryMessage, CloseMessage, PingMessage and
+// PongMessage) are supported.
 func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
 	if err := c.prepWrite(messageType); err != nil {
 		return nil, err
@@ -599,6 +605,10 @@ func (w *messageWriter) flushFrame(final bool, extra []byte) error {
 
 	if final {
 		c.writer = nil
+		if c.writePool != nil {
+			c.writePool.Put(writePoolData{buf: c.writeBuf})
+			c.writeBuf = nil
+		}
 		return nil
 	}
 
@@ -764,7 +774,6 @@ func (c *Conn) SetWriteDeadline(t time.Time) error {
 // Read methods
 
 func (c *Conn) advanceFrame() (int, error) {
-
 	// 1. Skip remainder of previous frame.
 
 	if c.readRemaining > 0 {
@@ -1033,7 +1042,7 @@ func (c *Conn) SetReadDeadline(t time.Time) error {
 }
 
 // SetReadLimit sets the maximum size for a message read from the peer. If a
-// message exceeds the limit, the connection sends a close frame to the peer
+// message exceeds the limit, the connection sends a close message to the peer
 // and returns ErrReadLimit to the application.
 func (c *Conn) SetReadLimit(limit int64) {
 	c.readLimit = limit
@@ -1046,24 +1055,22 @@ func (c *Conn) CloseHandler() func(code int, text string) error {
 
 // SetCloseHandler sets the handler for close messages received from the peer.
 // The code argument to h is the received close code or CloseNoStatusReceived
-// if the close message is empty. The default close handler sends a close frame
-// back to the peer.
+// if the close message is empty. The default close handler sends a close
+// message back to the peer.
 //
-// The application must read the connection to process close messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// close messages as described in the section on Control Messages above.
 //
-// The connection read methods return a CloseError when a close frame is
+// The connection read methods return a CloseError when a close message is
 // received. Most applications should handle close messages as part of their
 // normal error handling. Applications should only set a close handler when the
-// application must perform some action before sending a close frame back to
+// application must perform some action before sending a close message back to
 // the peer.
 func (c *Conn) SetCloseHandler(h func(code int, text string) error) {
 	if h == nil {
 		h = func(code int, text string) error {
-			message := []byte{}
-			if code != CloseNoStatusReceived {
-				message = FormatCloseMessage(code, "")
-			}
+			message := FormatCloseMessage(code, "")
 			c.WriteControl(CloseMessage, message, time.Now().Add(writeWait))
 			return nil
 		}
@@ -1077,11 +1084,12 @@ func (c *Conn) PingHandler() func(appData string) error {
 }
 
 // SetPingHandler sets the handler for ping messages received from the peer.
-// The appData argument to h is the PING frame application data. The default
+// The appData argument to h is the PING message application data. The default
 // ping handler sends a pong to the peer.
 //
-// The application must read the connection to process ping messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// ping messages as described in the section on Control Messages above.
 func (c *Conn) SetPingHandler(h func(appData string) error) {
 	if h == nil {
 		h = func(message string) error {
@@ -1103,11 +1111,12 @@ func (c *Conn) PongHandler() func(appData string) error {
 }
 
 // SetPongHandler sets the handler for pong messages received from the peer.
-// The appData argument to h is the PONG frame application data. The default
+// The appData argument to h is the PONG message application data. The default
 // pong handler does nothing.
 //
-// The application must read the connection to process ping messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// pong messages as described in the section on Control Messages above.
 func (c *Conn) SetPongHandler(h func(appData string) error) {
 	if h == nil {
 		h = func(string) error { return nil }
@@ -1141,7 +1150,14 @@ func (c *Conn) SetCompressionLevel(level int) error {
 }
 
 // FormatCloseMessage formats closeCode and text as a WebSocket close message.
+// An empty message is returned for code CloseNoStatusReceived.
 func FormatCloseMessage(closeCode int, text string) []byte {
+	if closeCode == CloseNoStatusReceived {
+		// Return empty message because it's illegal to send
+		// CloseNoStatusReceived. Return non-nil value in case application
+		// checks for nil.
+		return []byte{}
+	}
 	buf := make([]byte, 2+len(text))
 	binary.BigEndian.PutUint16(buf, uint16(closeCode))
 	copy(buf[2:], text)
diff --git a/vendor/github.com/gorilla/websocket/conn_read_legacy.go b/vendor/github.com/gorilla/websocket/conn_read_legacy.go
deleted file mode 100644
index 018541cf..00000000
--- a/vendor/github.com/gorilla/websocket/conn_read_legacy.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build !go1.5
-
-package websocket
-
-import "io"
-
-func (c *Conn) read(n int) ([]byte, error) {
-	p, err := c.br.Peek(n)
-	if err == io.EOF {
-		err = errUnexpectedEOF
-	}
-	if len(p) > 0 {
-		// advance over the bytes just read
-		io.ReadFull(c.br, p)
-	}
-	return p, err
-}
diff --git a/vendor/github.com/gorilla/websocket/conn_read.go b/vendor/github.com/gorilla/websocket/conn_write.go
index 1ea15059..a509a21f 100644
--- a/vendor/github.com/gorilla/websocket/conn_read.go
+++ b/vendor/github.com/gorilla/websocket/conn_write.go
@@ -2,17 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build go1.5
+// +build go1.8
 
 package websocket
 
-import "io"
+import "net"
 
-func (c *Conn) read(n int) ([]byte, error) {
-	p, err := c.br.Peek(n)
-	if err == io.EOF {
-		err = errUnexpectedEOF
-	}
-	c.br.Discard(len(p))
-	return p, err
+func (c *Conn) writeBufs(bufs ...[]byte) error {
+	b := net.Buffers(bufs)
+	_, err := b.WriteTo(c.conn)
+	return err
 }
diff --git a/vendor/github.com/gorilla/websocket/conn_write_legacy.go b/vendor/github.com/gorilla/websocket/conn_write_legacy.go
new file mode 100644
index 00000000..37edaff5
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/conn_write_legacy.go
@@ -0,0 +1,18 @@
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.8
+
+package websocket
+
+func (c *Conn) writeBufs(bufs ...[]byte) error {
+	for _, buf := range bufs {
+		if len(buf) > 0 {
+			if _, err := c.conn.Write(buf); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/gorilla/websocket/doc.go b/vendor/github.com/gorilla/websocket/doc.go
index e291a952..dcce1a63 100644
--- a/vendor/github.com/gorilla/websocket/doc.go
+++ b/vendor/github.com/gorilla/websocket/doc.go
@@ -6,9 +6,8 @@
 //
 // Overview
 //
-// The Conn type represents a WebSocket connection. A server application uses
-// the Upgrade function from an Upgrader object with a HTTP request handler
-// to get a pointer to a Conn:
+// The Conn type represents a WebSocket connection. A server application calls
+// the Upgrader.Upgrade method from an HTTP request handler to get a *Conn:
 //
 //  var upgrader = websocket.Upgrader{
 //      ReadBufferSize:  1024,
@@ -31,10 +30,12 @@
 //  for {
 //      messageType, p, err := conn.ReadMessage()
 //      if err != nil {
+//          log.Println(err)
 //          return
 //      }
-//      if err = conn.WriteMessage(messageType, p); err != nil {
-//          return err
+//      if err := conn.WriteMessage(messageType, p); err != nil {
+//          log.Println(err)
+//          return
 //      }
 //  }
 //
@@ -85,20 +86,26 @@
 // and pong. Call the connection WriteControl, WriteMessage or NextWriter
 // methods to send a control message to the peer.
 //
-// Connections handle received close messages by sending a close message to the
-// peer and returning a *CloseError from the the NextReader, ReadMessage or the
-// message Read method.
+// Connections handle received close messages by calling the handler function
+// set with the SetCloseHandler method and by returning a *CloseError from the
+// NextReader, ReadMessage or the message Read method. The default close
+// handler sends a close message to the peer.
 //
-// Connections handle received ping and pong messages by invoking callback
-// functions set with SetPingHandler and SetPongHandler methods. The callback
-// functions are called from the NextReader, ReadMessage and the message Read
-// methods.
+// Connections handle received ping messages by calling the handler function
+// set with the SetPingHandler method. The default ping handler sends a pong
+// message to the peer.
 //
-// The default ping handler sends a pong to the peer. The application's reading
-// goroutine can block for a short time while the handler writes the pong data
-// to the connection.
+// Connections handle received pong messages by calling the handler function
+// set with the SetPongHandler method. The default pong handler does nothing.
+// If an application sends ping messages, then the application should set a
+// pong handler to receive the corresponding pong.
 //
-// The application must read the connection to process ping, pong and close
+// The control message handler functions are called from the NextReader,
+// ReadMessage and message reader Read methods. The default close and ping
+// handlers can block these methods for a short time when the handler writes to
+// the connection.
+//
+// The application must read the connection to process close, ping and pong
 // messages sent from the peer. If the application is not otherwise interested
 // in messages from the peer, then the application should start a goroutine to
 // read and discard messages from the peer. A simple example is:
@@ -137,19 +144,12 @@
 // method fails the WebSocket handshake with HTTP status 403.
 //
 // If the CheckOrigin field is nil, then the Upgrader uses a safe default: fail
-// the handshake if the Origin request header is present and not equal to the
-// Host request header.
-//
-// An application can allow connections from any origin by specifying a
-// function that always returns true:
-//
-//  var upgrader = websocket.Upgrader{
-//      CheckOrigin: func(r *http.Request) bool { return true },
-//  }
+// the handshake if the Origin request header is present and the Origin host is
+// not equal to the Host request header.
 //
-// The deprecated Upgrade function does not enforce an origin policy. It's the
-// application's responsibility to check the Origin header before calling
-// Upgrade.
+// The deprecated package-level Upgrade function does not perform origin
+// checking. The application is responsible for checking the Origin header
+// before calling the Upgrade function.
 //
 // Compression EXPERIMENTAL
 //
diff --git a/vendor/github.com/gorilla/websocket/json.go b/vendor/github.com/gorilla/websocket/json.go
index 4f0e3687..dc2c1f64 100644
--- a/vendor/github.com/gorilla/websocket/json.go
+++ b/vendor/github.com/gorilla/websocket/json.go
@@ -9,12 +9,14 @@ import (
 	"io"
 )
 
-// WriteJSON is deprecated, use c.WriteJSON instead.
+// WriteJSON writes the JSON encoding of v as a message.
+//
+// Deprecated: Use c.WriteJSON instead.
 func WriteJSON(c *Conn, v interface{}) error {
 	return c.WriteJSON(v)
 }
 
-// WriteJSON writes the JSON encoding of v to the connection.
+// WriteJSON writes the JSON encoding of v as a message.
 //
 // See the documentation for encoding/json Marshal for details about the
 // conversion of Go values to JSON.
@@ -31,7 +33,10 @@ func (c *Conn) WriteJSON(v interface{}) error {
 	return err2
 }
 
-// ReadJSON is deprecated, use c.ReadJSON instead.
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// Deprecated: Use c.ReadJSON instead.
 func ReadJSON(c *Conn, v interface{}) error {
 	return c.ReadJSON(v)
 }
diff --git a/vendor/github.com/gorilla/websocket/mask.go b/vendor/github.com/gorilla/websocket/mask.go
index 6a88bbc7..577fce9e 100644
--- a/vendor/github.com/gorilla/websocket/mask.go
+++ b/vendor/github.com/gorilla/websocket/mask.go
@@ -11,7 +11,6 @@ import "unsafe"
 const wordSize = int(unsafe.Sizeof(uintptr(0)))
 
 func maskBytes(key [4]byte, pos int, b []byte) int {
-
 	// Mask one byte at a time for small buffers.
 	if len(b) < 2*wordSize {
 		for i := range b {
diff --git a/vendor/github.com/gorilla/websocket/prepared.go b/vendor/github.com/gorilla/websocket/prepared.go
index 1efffbd1..74ec565d 100644
--- a/vendor/github.com/gorilla/websocket/prepared.go
+++ b/vendor/github.com/gorilla/websocket/prepared.go
@@ -19,7 +19,6 @@ import (
 type PreparedMessage struct {
 	messageType int
 	data        []byte
-	err         error
 	mu          sync.Mutex
 	frames      map[prepareKey]*preparedFrame
 }
diff --git a/vendor/github.com/gorilla/websocket/proxy.go b/vendor/github.com/gorilla/websocket/proxy.go
new file mode 100644
index 00000000..bf2478e4
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/proxy.go
@@ -0,0 +1,77 @@
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"encoding/base64"
+	"errors"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type netDialerFunc func(network, addr string) (net.Conn, error)
+
+func (fn netDialerFunc) Dial(network, addr string) (net.Conn, error) {
+	return fn(network, addr)
+}
+
+func init() {
+	proxy_RegisterDialerType("http", func(proxyURL *url.URL, forwardDialer proxy_Dialer) (proxy_Dialer, error) {
+		return &httpProxyDialer{proxyURL: proxyURL, fowardDial: forwardDialer.Dial}, nil
+	})
+}
+
+type httpProxyDialer struct {
+	proxyURL   *url.URL
+	fowardDial func(network, addr string) (net.Conn, error)
+}
+
+func (hpd *httpProxyDialer) Dial(network string, addr string) (net.Conn, error) {
+	hostPort, _ := hostPortNoPort(hpd.proxyURL)
+	conn, err := hpd.fowardDial(network, hostPort)
+	if err != nil {
+		return nil, err
+	}
+
+	connectHeader := make(http.Header)
+	if user := hpd.proxyURL.User; user != nil {
+		proxyUser := user.Username()
+		if proxyPassword, passwordSet := user.Password(); passwordSet {
+			credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
+			connectHeader.Set("Proxy-Authorization", "Basic "+credential)
+		}
+	}
+
+	connectReq := &http.Request{
+		Method: "CONNECT",
+		URL:    &url.URL{Opaque: addr},
+		Host:   addr,
+		Header: connectHeader,
+	}
+
+	if err := connectReq.Write(conn); err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	// Read response. It's OK to use and discard buffered reader here becaue
+	// the remote server does not speak until spoken to.
+	br := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(br, connectReq)
+	if err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	if resp.StatusCode != 200 {
+		conn.Close()
+		f := strings.SplitN(resp.Status, " ", 2)
+		return nil, errors.New(f[1])
+	}
+	return conn, nil
+}
diff --git a/vendor/github.com/gorilla/websocket/server.go b/vendor/github.com/gorilla/websocket/server.go
index 3495e0f1..a761824b 100644
--- a/vendor/github.com/gorilla/websocket/server.go
+++ b/vendor/github.com/gorilla/websocket/server.go
@@ -7,7 +7,7 @@ package websocket
 import (
 	"bufio"
 	"errors"
-	"net"
+	"io"
 	"net/http"
 	"net/url"
 	"strings"
@@ -33,10 +33,23 @@ type Upgrader struct {
 	// or received.
 	ReadBufferSize, WriteBufferSize int
 
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
 	// Subprotocols specifies the server's supported protocols in order of
-	// preference. If this field is set, then the Upgrade method negotiates a
+	// preference. If this field is not nil, then the Upgrade method negotiates a
 	// subprotocol by selecting the first match in this list with a protocol
-	// requested by the client.
+	// requested by the client. If there's no match, then no protocol is
+	// negotiated (the Sec-Websocket-Protocol header is not included in the
+	// handshake response).
 	Subprotocols []string
 
 	// Error specifies the function for generating HTTP error responses. If Error
@@ -44,8 +57,12 @@ type Upgrader struct {
 	Error func(w http.ResponseWriter, r *http.Request, status int, reason error)
 
 	// CheckOrigin returns true if the request Origin header is acceptable. If
-	// CheckOrigin is nil, the host in the Origin header must not be set or
-	// must match the host of the request.
+	// CheckOrigin is nil, then a safe default is used: return false if the
+	// Origin request header is present and the origin host is not equal to
+	// request Host header.
+	//
+	// A CheckOrigin function should carefully validate the request origin to
+	// prevent cross-site request forgery.
 	CheckOrigin func(r *http.Request) bool
 
 	// EnableCompression specify if the server should attempt to negotiate per
@@ -76,7 +93,7 @@ func checkSameOrigin(r *http.Request) bool {
 	if err != nil {
 		return false
 	}
-	return u.Host == r.Host
+	return equalASCIIFold(u.Host, r.Host)
 }
 
 func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string {
@@ -99,42 +116,44 @@ func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header
 //
 // The responseHeader is included in the response to the client's upgrade
 // request. Use the responseHeader to specify cookies (Set-Cookie) and the
-// application negotiated subprotocol (Sec-Websocket-Protocol).
+// application negotiated subprotocol (Sec-WebSocket-Protocol).
 //
 // If the upgrade fails, then Upgrade replies to the client with an HTTP error
 // response.
 func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) {
-	if r.Method != "GET" {
-		return u.returnError(w, r, http.StatusMethodNotAllowed, "websocket: not a websocket handshake: request method is not GET")
-	}
-
-	if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok {
-		return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific 'Sec-Websocket-Extensions' headers are unsupported")
-	}
+	const badHandshake = "websocket: the client is not using the websocket protocol: "
 
 	if !tokenListContainsValue(r.Header, "Connection", "upgrade") {
-		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: 'upgrade' token not found in 'Connection' header")
+		return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'upgrade' token not found in 'Connection' header")
 	}
 
 	if !tokenListContainsValue(r.Header, "Upgrade", "websocket") {
-		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: 'websocket' token not found in 'Upgrade' header")
+		return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'websocket' token not found in 'Upgrade' header")
+	}
+
+	if r.Method != "GET" {
+		return u.returnError(w, r, http.StatusMethodNotAllowed, badHandshake+"request method is not GET")
 	}
 
 	if !tokenListContainsValue(r.Header, "Sec-Websocket-Version", "13") {
 		return u.returnError(w, r, http.StatusBadRequest, "websocket: unsupported version: 13 not found in 'Sec-Websocket-Version' header")
 	}
 
+	if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific 'Sec-WebSocket-Extensions' headers are unsupported")
+	}
+
 	checkOrigin := u.CheckOrigin
 	if checkOrigin == nil {
 		checkOrigin = checkSameOrigin
 	}
 	if !checkOrigin(r) {
-		return u.returnError(w, r, http.StatusForbidden, "websocket: 'Origin' header value not allowed")
+		return u.returnError(w, r, http.StatusForbidden, "websocket: request origin not allowed by Upgrader.CheckOrigin")
 	}
 
 	challengeKey := r.Header.Get("Sec-Websocket-Key")
 	if challengeKey == "" {
-		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: `Sec-Websocket-Key' header is missing or blank")
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: `Sec-WebSocket-Key' header is missing or blank")
 	}
 
 	subprotocol := u.selectSubprotocol(r, responseHeader)
@@ -151,17 +170,12 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 		}
 	}
 
-	var (
-		netConn net.Conn
-		err     error
-	)
-
 	h, ok := w.(http.Hijacker)
 	if !ok {
 		return u.returnError(w, r, http.StatusInternalServerError, "websocket: response does not implement http.Hijacker")
 	}
 	var brw *bufio.ReadWriter
-	netConn, brw, err = h.Hijack()
+	netConn, brw, err := h.Hijack()
 	if err != nil {
 		return u.returnError(w, r, http.StatusInternalServerError, err.Error())
 	}
@@ -171,7 +185,21 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 		return nil, errors.New("websocket: client sent data before handshake is complete")
 	}
 
-	c := newConnBRW(netConn, true, u.ReadBufferSize, u.WriteBufferSize, brw)
+	var br *bufio.Reader
+	if u.ReadBufferSize == 0 && bufioReaderSize(netConn, brw.Reader) > 256 {
+		// Reuse hijacked buffered reader as connection reader.
+		br = brw.Reader
+	}
+
+	buf := bufioWriterBuffer(netConn, brw.Writer)
+
+	var writeBuf []byte
+	if u.WriteBufferPool == nil && u.WriteBufferSize == 0 && len(buf) >= maxFrameHeaderSize+256 {
+		// Reuse hijacked write buffer as connection buffer.
+		writeBuf = buf
+	}
+
+	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize, u.WriteBufferPool, br, writeBuf)
 	c.subprotocol = subprotocol
 
 	if compress {
@@ -179,17 +207,23 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 		c.newDecompressionReader = decompressNoContextTakeover
 	}
 
-	p := c.writeBuf[:0]
+	// Use larger of hijacked buffer and connection write buffer for header.
+	p := buf
+	if len(c.writeBuf) > len(p) {
+		p = c.writeBuf
+	}
+	p = p[:0]
+
 	p = append(p, "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "...)
 	p = append(p, computeAcceptKey(challengeKey)...)
 	p = append(p, "\r\n"...)
 	if c.subprotocol != "" {
-		p = append(p, "Sec-Websocket-Protocol: "...)
+		p = append(p, "Sec-WebSocket-Protocol: "...)
 		p = append(p, c.subprotocol...)
 		p = append(p, "\r\n"...)
 	}
 	if compress {
-		p = append(p, "Sec-Websocket-Extensions: permessage-deflate; server_no_context_takeover; client_no_context_takeover\r\n"...)
+		p = append(p, "Sec-WebSocket-Extensions: permessage-deflate; server_no_context_takeover; client_no_context_takeover\r\n"...)
 	}
 	for k, vs := range responseHeader {
 		if k == "Sec-Websocket-Protocol" {
@@ -230,13 +264,14 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 
 // Upgrade upgrades the HTTP server connection to the WebSocket protocol.
 //
-// This function is deprecated, use websocket.Upgrader instead.
+// Deprecated: Use websocket.Upgrader instead.
 //
-// The application is responsible for checking the request origin before
-// calling Upgrade. An example implementation of the same origin policy is:
+// Upgrade does not perform origin checking. The application is responsible for
+// checking the Origin header before calling Upgrade. An example implementation
+// of the same origin policy check is:
 //
 //	if req.Header.Get("Origin") != "http://"+req.Host {
-//		http.Error(w, "Origin not allowed", 403)
+//		http.Error(w, "Origin not allowed", http.StatusForbidden)
 //		return
 //	}
 //
@@ -289,3 +324,40 @@ func IsWebSocketUpgrade(r *http.Request) bool {
 	return tokenListContainsValue(r.Header, "Connection", "upgrade") &&
 		tokenListContainsValue(r.Header, "Upgrade", "websocket")
 }
+
+// bufioReaderSize size returns the size of a bufio.Reader.
+func bufioReaderSize(originalReader io.Reader, br *bufio.Reader) int {
+	// This code assumes that peek on a reset reader returns
+	// bufio.Reader.buf[:0].
+	// TODO: Use bufio.Reader.Size() after Go 1.10
+	br.Reset(originalReader)
+	if p, err := br.Peek(0); err == nil {
+		return cap(p)
+	}
+	return 0
+}
+
+// writeHook is an io.Writer that records the last slice passed to it vio
+// io.Writer.Write.
+type writeHook struct {
+	p []byte
+}
+
+func (wh *writeHook) Write(p []byte) (int, error) {
+	wh.p = p
+	return len(p), nil
+}
+
+// bufioWriterBuffer grabs the buffer from a bufio.Writer.
+func bufioWriterBuffer(originalWriter io.Writer, bw *bufio.Writer) []byte {
+	// This code assumes that bufio.Writer.buf[:1] is passed to the
+	// bufio.Writer's underlying writer.
+	var wh writeHook
+	bw.Reset(&wh)
+	bw.WriteByte(0)
+	bw.Flush()
+
+	bw.Reset(originalWriter)
+
+	return wh.p[:cap(wh.p)]
+}
diff --git a/vendor/github.com/gorilla/websocket/trace.go b/vendor/github.com/gorilla/websocket/trace.go
new file mode 100644
index 00000000..834f122a
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/trace.go
@@ -0,0 +1,19 @@
+// +build go1.8
+
+package websocket
+
+import (
+	"crypto/tls"
+	"net/http/httptrace"
+)
+
+func doHandshakeWithTrace(trace *httptrace.ClientTrace, tlsConn *tls.Conn, cfg *tls.Config) error {
+	if trace.TLSHandshakeStart != nil {
+		trace.TLSHandshakeStart()
+	}
+	err := doHandshake(tlsConn, cfg)
+	if trace.TLSHandshakeDone != nil {
+		trace.TLSHandshakeDone(tlsConn.ConnectionState(), err)
+	}
+	return err
+}
diff --git a/vendor/github.com/gorilla/websocket/trace_17.go b/vendor/github.com/gorilla/websocket/trace_17.go
new file mode 100644
index 00000000..77d05a0b
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/trace_17.go
@@ -0,0 +1,12 @@
+// +build !go1.8
+
+package websocket
+
+import (
+	"crypto/tls"
+	"net/http/httptrace"
+)
+
+func doHandshakeWithTrace(trace *httptrace.ClientTrace, tlsConn *tls.Conn, cfg *tls.Config) error {
+	return doHandshake(tlsConn, cfg)
+}
diff --git a/vendor/github.com/gorilla/websocket/util.go b/vendor/github.com/gorilla/websocket/util.go
index 9a4908df..354001e1 100644
--- a/vendor/github.com/gorilla/websocket/util.go
+++ b/vendor/github.com/gorilla/websocket/util.go
@@ -11,6 +11,7 @@ import (
 	"io"
 	"net/http"
 	"strings"
+	"unicode/utf8"
 )
 
 var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
@@ -111,14 +112,14 @@ func nextTokenOrQuoted(s string) (value string, rest string) {
 				case escape:
 					escape = false
 					p[j] = b
-					j += 1
+					j++
 				case b == '\\':
 					escape = true
 				case b == '"':
 					return string(p[:j]), s[i+1:]
 				default:
 					p[j] = b
-					j += 1
+					j++
 				}
 			}
 			return "", ""
@@ -127,8 +128,31 @@ func nextTokenOrQuoted(s string) (value string, rest string) {
 	return "", ""
 }
 
+// equalASCIIFold returns true if s is equal to t with ASCII case folding.
+func equalASCIIFold(s, t string) bool {
+	for s != "" && t != "" {
+		sr, size := utf8.DecodeRuneInString(s)
+		s = s[size:]
+		tr, size := utf8.DecodeRuneInString(t)
+		t = t[size:]
+		if sr == tr {
+			continue
+		}
+		if 'A' <= sr && sr <= 'Z' {
+			sr = sr + 'a' - 'A'
+		}
+		if 'A' <= tr && tr <= 'Z' {
+			tr = tr + 'a' - 'A'
+		}
+		if sr != tr {
+			return false
+		}
+	}
+	return s == t
+}
+
 // tokenListContainsValue returns true if the 1#token header with the given
-// name contains token.
+// name contains a token equal to value with ASCII case folding.
 func tokenListContainsValue(header http.Header, name string, value string) bool {
 headers:
 	for _, s := range header[name] {
@@ -142,7 +166,7 @@ headers:
 			if s != "" && s[0] != ',' {
 				continue headers
 			}
-			if strings.EqualFold(t, value) {
+			if equalASCIIFold(t, value) {
 				return true
 			}
 			if s == "" {
@@ -154,9 +178,8 @@ headers:
 	return false
 }
 
-// parseExtensiosn parses WebSocket extensions from a header.
+// parseExtensions parses WebSocket extensions from a header.
 func parseExtensions(header http.Header) []map[string]string {
-
 	// From RFC 6455:
 	//
 	//  Sec-WebSocket-Extensions = extension-list
diff --git a/vendor/github.com/gorilla/websocket/x_net_proxy.go b/vendor/github.com/gorilla/websocket/x_net_proxy.go
new file mode 100644
index 00000000..2e668f6b
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/x_net_proxy.go
@@ -0,0 +1,473 @@
+// Code generated by golang.org/x/tools/cmd/bundle. DO NOT EDIT.
+//go:generate bundle -o x_net_proxy.go golang.org/x/net/proxy
+
+// Package proxy provides support for a variety of protocols to proxy network
+// data.
+//
+
+package websocket
+
+import (
+	"errors"
+	"io"
+	"net"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+type proxy_direct struct{}
+
+// Direct is a direct proxy: one that makes network connections directly.
+var proxy_Direct = proxy_direct{}
+
+func (proxy_direct) Dial(network, addr string) (net.Conn, error) {
+	return net.Dial(network, addr)
+}
+
+// A PerHost directs connections to a default Dialer unless the host name
+// requested matches one of a number of exceptions.
+type proxy_PerHost struct {
+	def, bypass proxy_Dialer
+
+	bypassNetworks []*net.IPNet
+	bypassIPs      []net.IP
+	bypassZones    []string
+	bypassHosts    []string
+}
+
+// NewPerHost returns a PerHost Dialer that directs connections to either
+// defaultDialer or bypass, depending on whether the connection matches one of
+// the configured rules.
+func proxy_NewPerHost(defaultDialer, bypass proxy_Dialer) *proxy_PerHost {
+	return &proxy_PerHost{
+		def:    defaultDialer,
+		bypass: bypass,
+	}
+}
+
+// Dial connects to the address addr on the given network through either
+// defaultDialer or bypass.
+func (p *proxy_PerHost) Dial(network, addr string) (c net.Conn, err error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return p.dialerForRequest(host).Dial(network, addr)
+}
+
+func (p *proxy_PerHost) dialerForRequest(host string) proxy_Dialer {
+	if ip := net.ParseIP(host); ip != nil {
+		for _, net := range p.bypassNetworks {
+			if net.Contains(ip) {
+				return p.bypass
+			}
+		}
+		for _, bypassIP := range p.bypassIPs {
+			if bypassIP.Equal(ip) {
+				return p.bypass
+			}
+		}
+		return p.def
+	}
+
+	for _, zone := range p.bypassZones {
+		if strings.HasSuffix(host, zone) {
+			return p.bypass
+		}
+		if host == zone[1:] {
+			// For a zone ".example.com", we match "example.com"
+			// too.
+			return p.bypass
+		}
+	}
+	for _, bypassHost := range p.bypassHosts {
+		if bypassHost == host {
+			return p.bypass
+		}
+	}
+	return p.def
+}
+
+// AddFromString parses a string that contains comma-separated values
+// specifying hosts that should use the bypass proxy. Each value is either an
+// IP address, a CIDR range, a zone (*.example.com) or a host name
+// (localhost). A best effort is made to parse the string and errors are
+// ignored.
+func (p *proxy_PerHost) AddFromString(s string) {
+	hosts := strings.Split(s, ",")
+	for _, host := range hosts {
+		host = strings.TrimSpace(host)
+		if len(host) == 0 {
+			continue
+		}
+		if strings.Contains(host, "/") {
+			// We assume that it's a CIDR address like 127.0.0.0/8
+			if _, net, err := net.ParseCIDR(host); err == nil {
+				p.AddNetwork(net)
+			}
+			continue
+		}
+		if ip := net.ParseIP(host); ip != nil {
+			p.AddIP(ip)
+			continue
+		}
+		if strings.HasPrefix(host, "*.") {
+			p.AddZone(host[1:])
+			continue
+		}
+		p.AddHost(host)
+	}
+}
+
+// AddIP specifies an IP address that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match an IP.
+func (p *proxy_PerHost) AddIP(ip net.IP) {
+	p.bypassIPs = append(p.bypassIPs, ip)
+}
+
+// AddNetwork specifies an IP range that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match.
+func (p *proxy_PerHost) AddNetwork(net *net.IPNet) {
+	p.bypassNetworks = append(p.bypassNetworks, net)
+}
+
+// AddZone specifies a DNS suffix that will use the bypass proxy. A zone of
+// "example.com" matches "example.com" and all of its subdomains.
+func (p *proxy_PerHost) AddZone(zone string) {
+	if strings.HasSuffix(zone, ".") {
+		zone = zone[:len(zone)-1]
+	}
+	if !strings.HasPrefix(zone, ".") {
+		zone = "." + zone
+	}
+	p.bypassZones = append(p.bypassZones, zone)
+}
+
+// AddHost specifies a host name that will use the bypass proxy.
+func (p *proxy_PerHost) AddHost(host string) {
+	if strings.HasSuffix(host, ".") {
+		host = host[:len(host)-1]
+	}
+	p.bypassHosts = append(p.bypassHosts, host)
+}
+
+// A Dialer is a means to establish a connection.
+type proxy_Dialer interface {
+	// Dial connects to the given address via the proxy.
+	Dial(network, addr string) (c net.Conn, err error)
+}
+
+// Auth contains authentication parameters that specific Dialers may require.
+type proxy_Auth struct {
+	User, Password string
+}
+
+// FromEnvironment returns the dialer specified by the proxy related variables in
+// the environment.
+func proxy_FromEnvironment() proxy_Dialer {
+	allProxy := proxy_allProxyEnv.Get()
+	if len(allProxy) == 0 {
+		return proxy_Direct
+	}
+
+	proxyURL, err := url.Parse(allProxy)
+	if err != nil {
+		return proxy_Direct
+	}
+	proxy, err := proxy_FromURL(proxyURL, proxy_Direct)
+	if err != nil {
+		return proxy_Direct
+	}
+
+	noProxy := proxy_noProxyEnv.Get()
+	if len(noProxy) == 0 {
+		return proxy
+	}
+
+	perHost := proxy_NewPerHost(proxy, proxy_Direct)
+	perHost.AddFromString(noProxy)
+	return perHost
+}
+
+// proxySchemes is a map from URL schemes to a function that creates a Dialer
+// from a URL with such a scheme.
+var proxy_proxySchemes map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error)
+
+// RegisterDialerType takes a URL scheme and a function to generate Dialers from
+// a URL with that scheme and a forwarding Dialer. Registered schemes are used
+// by FromURL.
+func proxy_RegisterDialerType(scheme string, f func(*url.URL, proxy_Dialer) (proxy_Dialer, error)) {
+	if proxy_proxySchemes == nil {
+		proxy_proxySchemes = make(map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error))
+	}
+	proxy_proxySchemes[scheme] = f
+}
+
+// FromURL returns a Dialer given a URL specification and an underlying
+// Dialer for it to make network requests.
+func proxy_FromURL(u *url.URL, forward proxy_Dialer) (proxy_Dialer, error) {
+	var auth *proxy_Auth
+	if u.User != nil {
+		auth = new(proxy_Auth)
+		auth.User = u.User.Username()
+		if p, ok := u.User.Password(); ok {
+			auth.Password = p
+		}
+	}
+
+	switch u.Scheme {
+	case "socks5":
+		return proxy_SOCKS5("tcp", u.Host, auth, forward)
+	}
+
+	// If the scheme doesn't match any of the built-in schemes, see if it
+	// was registered by another package.
+	if proxy_proxySchemes != nil {
+		if f, ok := proxy_proxySchemes[u.Scheme]; ok {
+			return f(u, forward)
+		}
+	}
+
+	return nil, errors.New("proxy: unknown scheme: " + u.Scheme)
+}
+
+var (
+	proxy_allProxyEnv = &proxy_envOnce{
+		names: []string{"ALL_PROXY", "all_proxy"},
+	}
+	proxy_noProxyEnv = &proxy_envOnce{
+		names: []string{"NO_PROXY", "no_proxy"},
+	}
+)
+
+// envOnce looks up an environment variable (optionally by multiple
+// names) once. It mitigates expensive lookups on some platforms
+// (e.g. Windows).
+// (Borrowed from net/http/transport.go)
+type proxy_envOnce struct {
+	names []string
+	once  sync.Once
+	val   string
+}
+
+func (e *proxy_envOnce) Get() string {
+	e.once.Do(e.init)
+	return e.val
+}
+
+func (e *proxy_envOnce) init() {
+	for _, n := range e.names {
+		e.val = os.Getenv(n)
+		if e.val != "" {
+			return
+		}
+	}
+}
+
+// SOCKS5 returns a Dialer that makes SOCKSv5 connections to the given address
+// with an optional username and password. See RFC 1928 and RFC 1929.
+func proxy_SOCKS5(network, addr string, auth *proxy_Auth, forward proxy_Dialer) (proxy_Dialer, error) {
+	s := &proxy_socks5{
+		network: network,
+		addr:    addr,
+		forward: forward,
+	}
+	if auth != nil {
+		s.user = auth.User
+		s.password = auth.Password
+	}
+
+	return s, nil
+}
+
+type proxy_socks5 struct {
+	user, password string
+	network, addr  string
+	forward        proxy_Dialer
+}
+
+const proxy_socks5Version = 5
+
+const (
+	proxy_socks5AuthNone     = 0
+	proxy_socks5AuthPassword = 2
+)
+
+const proxy_socks5Connect = 1
+
+const (
+	proxy_socks5IP4    = 1
+	proxy_socks5Domain = 3
+	proxy_socks5IP6    = 4
+)
+
+var proxy_socks5Errors = []string{
+	"",
+	"general failure",
+	"connection forbidden",
+	"network unreachable",
+	"host unreachable",
+	"connection refused",
+	"TTL expired",
+	"command not supported",
+	"address type not supported",
+}
+
+// Dial connects to the address addr on the given network via the SOCKS5 proxy.
+func (s *proxy_socks5) Dial(network, addr string) (net.Conn, error) {
+	switch network {
+	case "tcp", "tcp6", "tcp4":
+	default:
+		return nil, errors.New("proxy: no support for SOCKS5 proxy connections of type " + network)
+	}
+
+	conn, err := s.forward.Dial(s.network, s.addr)
+	if err != nil {
+		return nil, err
+	}
+	if err := s.connect(conn, addr); err != nil {
+		conn.Close()
+		return nil, err
+	}
+	return conn, nil
+}
+
+// connect takes an existing connection to a socks5 proxy server,
+// and commands the server to extend that connection to target,
+// which must be a canonical address with a host and port.
+func (s *proxy_socks5) connect(conn net.Conn, target string) error {
+	host, portStr, err := net.SplitHostPort(target)
+	if err != nil {
+		return err
+	}
+
+	port, err := strconv.Atoi(portStr)
+	if err != nil {
+		return errors.New("proxy: failed to parse port number: " + portStr)
+	}
+	if port < 1 || port > 0xffff {
+		return errors.New("proxy: port number out of range: " + portStr)
+	}
+
+	// the size here is just an estimate
+	buf := make([]byte, 0, 6+len(host))
+
+	buf = append(buf, proxy_socks5Version)
+	if len(s.user) > 0 && len(s.user) < 256 && len(s.password) < 256 {
+		buf = append(buf, 2 /* num auth methods */, proxy_socks5AuthNone, proxy_socks5AuthPassword)
+	} else {
+		buf = append(buf, 1 /* num auth methods */, proxy_socks5AuthNone)
+	}
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write greeting to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read greeting from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+	if buf[0] != 5 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " has unexpected version " + strconv.Itoa(int(buf[0])))
+	}
+	if buf[1] == 0xff {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " requires authentication")
+	}
+
+	// See RFC 1929
+	if buf[1] == proxy_socks5AuthPassword {
+		buf = buf[:0]
+		buf = append(buf, 1 /* password protocol version */)
+		buf = append(buf, uint8(len(s.user)))
+		buf = append(buf, s.user...)
+		buf = append(buf, uint8(len(s.password)))
+		buf = append(buf, s.password...)
+
+		if _, err := conn.Write(buf); err != nil {
+			return errors.New("proxy: failed to write authentication request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+			return errors.New("proxy: failed to read authentication reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if buf[1] != 0 {
+			return errors.New("proxy: SOCKS5 proxy at " + s.addr + " rejected username/password")
+		}
+	}
+
+	buf = buf[:0]
+	buf = append(buf, proxy_socks5Version, proxy_socks5Connect, 0 /* reserved */)
+
+	if ip := net.ParseIP(host); ip != nil {
+		if ip4 := ip.To4(); ip4 != nil {
+			buf = append(buf, proxy_socks5IP4)
+			ip = ip4
+		} else {
+			buf = append(buf, proxy_socks5IP6)
+		}
+		buf = append(buf, ip...)
+	} else {
+		if len(host) > 255 {
+			return errors.New("proxy: destination host name too long: " + host)
+		}
+		buf = append(buf, proxy_socks5Domain)
+		buf = append(buf, byte(len(host)))
+		buf = append(buf, host...)
+	}
+	buf = append(buf, byte(port>>8), byte(port))
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write connect request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:4]); err != nil {
+		return errors.New("proxy: failed to read connect reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	failure := "unknown error"
+	if int(buf[1]) < len(proxy_socks5Errors) {
+		failure = proxy_socks5Errors[buf[1]]
+	}
+
+	if len(failure) > 0 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " failed to connect: " + failure)
+	}
+
+	bytesToDiscard := 0
+	switch buf[3] {
+	case proxy_socks5IP4:
+		bytesToDiscard = net.IPv4len
+	case proxy_socks5IP6:
+		bytesToDiscard = net.IPv6len
+	case proxy_socks5Domain:
+		_, err := io.ReadFull(conn, buf[:1])
+		if err != nil {
+			return errors.New("proxy: failed to read domain length from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+		bytesToDiscard = int(buf[0])
+	default:
+		return errors.New("proxy: got unknown address type " + strconv.Itoa(int(buf[3])) + " from SOCKS5 proxy at " + s.addr)
+	}
+
+	if cap(buf) < bytesToDiscard {
+		buf = make([]byte, bytesToDiscard)
+	} else {
+		buf = buf[:bytesToDiscard]
+	}
+	if _, err := io.ReadFull(conn, buf); err != nil {
+		return errors.New("proxy: failed to read address from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	// Also need to discard the port number
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read port from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	return nil
+}