Upgrading server dependancies (#4566)

vendor/github.com/gorilla/websocket/client.go

@@ -23,6 +23,8 @@ import (
 // invalid.
 var ErrBadHandshake = errors.New("websocket: bad handshake")
 
+var errInvalidCompression = errors.New("websocket: invalid compression negotiation")
+
 // NewClient creates a new client connection using the given net connection.
 // The URL u specifies the host and request URI. Use requestHeader to specify
 // the origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies
@@ -70,6 +72,17 @@ type Dialer struct {
 
 	// Subprotocols specifies the client's requested subprotocols.
 	Subprotocols []string
+
+	// EnableCompression specifies if the client should attempt to negotiate
+	// per message compression (RFC 7692). Setting this value to true does not
+	// guarantee that compression will be supported. Currently only "no context
+	// takeover" modes are supported.
+	EnableCompression bool
+
+	// Jar specifies the cookie jar.
+	// If Jar is nil, cookies are not sent in requests and ignored
+	// in responses.
+	Jar http.CookieJar
 }
 
 var errMalformedURL = errors.New("malformed ws or wss URL")
@@ -83,7 +96,6 @@ func parseURL(s string) (*url.URL, error) {
 	//
 	// ws-URI = "ws:" "//" host [ ":" port ] path [ "?" query ]
 	// wss-URI = "wss:" "//" host [ ":" port ] path [ "?" query ]
-
 	var u url.URL
 	switch {
 	case strings.HasPrefix(s, "ws://"):
@@ -193,6 +205,13 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		Host:       u.Host,
 	}
 
+	// Set the cookies present in the cookie jar of the dialer
+	if d.Jar != nil {
+		for _, cookie := range d.Jar.Cookies(u) {
+			req.AddCookie(cookie)
+		}
+	}
+
 	// Set the request headers using the capitalization for names and values in
 	// RFC examples. Although the capitalization shouldn't matter, there are
 	// servers that depend on it. The Header.Set method is not used because the
@@ -214,6 +233,7 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 			k == "Connection" ||
 			k == "Sec-Websocket-Key" ||
 			k == "Sec-Websocket-Version" ||
+			k == "Sec-Websocket-Extensions" ||
 			(k == "Sec-Websocket-Protocol" && len(d.Subprotocols) > 0):
 			return nil, nil, errors.New("websocket: duplicate header not allowed: " + k)
 		default:
@@ -221,6 +241,10 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 	}
 
+	if d.EnableCompression {
+		req.Header.Set("Sec-Websocket-Extensions", "permessage-deflate; server_no_context_takeover; client_no_context_takeover")
+	}
+
 	hostPort, hostNoPort := hostPortNoPort(u)
 
 	var proxyURL *url.URL
@@ -324,6 +348,13 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	if err != nil {
 		return nil, nil, err
 	}
+
+	if d.Jar != nil {
+		if rc := resp.Cookies(); len(rc) > 0 {
+			d.Jar.SetCookies(u, rc)
+		}
+	}
+
 	if resp.StatusCode != 101 ||
 		!strings.EqualFold(resp.Header.Get("Upgrade"), "websocket") ||
 		!strings.EqualFold(resp.Header.Get("Connection"), "upgrade") ||
@@ -337,6 +368,20 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		return nil, resp, ErrBadHandshake
 	}
 
+	for _, ext := range parseExtensions(req.Header) {
+		if ext[""] != "permessage-deflate" {
+			continue
+		}
+		_, snct := ext["server_no_context_takeover"]
+		_, cnct := ext["client_no_context_takeover"]
+		if !snct || !cnct {
+			return nil, resp, errInvalidCompression
+		}
+		conn.newCompressionWriter = compressNoContextTakeover
+		conn.newDecompressionReader = decompressNoContextTakeover
+		break
+	}
+
 	resp.Body = ioutil.NopCloser(bytes.NewReader([]byte{}))
 	conn.subprotocol = resp.Header.Get("Sec-Websocket-Protocol")