vendor change

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

@@ -6,12 +6,14 @@ package websocket
 
 import (
 	"bytes"
+	"context"
 	"crypto/tls"
 	"errors"
 	"io"
 	"io/ioutil"
 	"net"
 	"net/http"
+	"net/http/httptrace"
 	"net/url"
 	"strings"
 	"time"
@@ -21,6 +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
@@ -30,50 +34,17 @@ var ErrBadHandshake = errors.New("websocket: bad handshake")
 // If the WebSocket handshake fails, ErrBadHandshake is returned along with a
 // non-nil *http.Response so that callers can handle redirects, authentication,
 // etc.
+//
+// Deprecated: Use Dialer instead.
 func NewClient(netConn net.Conn, u *url.URL, requestHeader http.Header, readBufSize, writeBufSize int) (c *Conn, response *http.Response, err error) {
-	challengeKey, err := generateChallengeKey()
-	if err != nil {
-		return nil, nil, err
+	d := Dialer{
+		ReadBufferSize:  readBufSize,
+		WriteBufferSize: writeBufSize,
+		NetDial: func(net, addr string) (net.Conn, error) {
+			return netConn, nil
+		},
 	}
-	acceptKey := computeAcceptKey(challengeKey)
-
-	c = newConn(netConn, false, readBufSize, writeBufSize)
-	p := c.writeBuf[:0]
-	p = append(p, "GET "...)
-	p = append(p, u.RequestURI()...)
-	p = append(p, " HTTP/1.1\r\nHost: "...)
-	p = append(p, u.Host...)
-	// "Upgrade" is capitalized for servers that do not use case insensitive
-	// comparisons on header tokens.
-	p = append(p, "\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Version: 13\r\nSec-WebSocket-Key: "...)
-	p = append(p, challengeKey...)
-	p = append(p, "\r\n"...)
-	for k, vs := range requestHeader {
-		for _, v := range vs {
-			p = append(p, k...)
-			p = append(p, ": "...)
-			p = append(p, v...)
-			p = append(p, "\r\n"...)
-		}
-	}
-	p = append(p, "\r\n"...)
-
-	if _, err := netConn.Write(p); err != nil {
-		return nil, nil, err
-	}
-
-	resp, err := http.ReadResponse(c.br, &http.Request{Method: "GET", URL: u})
-	if err != nil {
-		return nil, nil, err
-	}
-	if resp.StatusCode != 101 ||
-		!strings.EqualFold(resp.Header.Get("Upgrade"), "websocket") ||
-		!strings.EqualFold(resp.Header.Get("Connection"), "upgrade") ||
-		resp.Header.Get("Sec-Websocket-Accept") != acceptKey {
-		return nil, resp, ErrBadHandshake
-	}
-	c.subprotocol = resp.Header.Get("Sec-Websocket-Protocol")
-	return c, resp, nil
+	return d.Dial(u.String(), requestHeader)
 }
 
 // A Dialer contains options for connecting to WebSocket server.
@@ -82,6 +53,16 @@ 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.
+	// If Proxy is nil or returns a nil *URL, no proxy is used.
+	Proxy func(*http.Request) (*url.URL, error)
+
 	// TLSClientConfig specifies the TLS configuration to use with tls.Client.
 	// If nil, the default configuration is used.
 	TLSClientConfig *tls.Config
@@ -89,106 +70,230 @@ type Dialer struct {
 	// HandshakeTimeout specifies the duration for the handshake to complete.
 	HandshakeTimeout time.Duration
 
-	// Input and output buffer sizes. If the buffer size is zero, then a
-	// default value of 4096 is used.
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes. If a buffer
+	// size is zero, then a useful default size is used. The I/O buffer sizes
+	// 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
+
+	// 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
+}
+
+// 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")
 
-// parseURL parses the URL. The url.Parse function is not used here because
-// url.Parse mangles 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 ]
-	//
-	// We don't use the net/url parser here because the dialer interface does
-	// not provide a way for applications to work around percent deocding in
-	// the net/url parser.
-
-	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
-	}
-
-	u.Host = s
-	u.Opaque = "/"
-	if i := strings.Index(s, "/"); i >= 0 {
-		u.Host = s[:i]
-		u.Opaque = s[i:]
-	}
-
-	if strings.Contains(u.Host, "@") {
-		// WebSocket URIs do not contain user information.
-		return nil, errMalformedURL
-	}
-
-	return &u, nil
-}
-
 func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
 	hostPort = u.Host
 	hostNoPort = u.Host
 	if i := strings.LastIndex(u.Host, ":"); i > strings.LastIndex(u.Host, "]") {
 		hostNoPort = hostNoPort[:i]
 	} else {
-		if u.Scheme == "wss" {
+		switch u.Scheme {
+		case "wss":
 			hostPort += ":443"
-		} else {
+		case "https":
+			hostPort += ":443"
+		default:
 			hostPort += ":80"
 		}
 	}
 	return hostPort, hostNoPort
 }
 
-// DefaultDialer is a dialer with all fields set to the default zero values.
-var DefaultDialer *Dialer
+// DefaultDialer is a dialer with all fields set to the default values.
+var DefaultDialer = &Dialer{
+	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) {
-	u, err := parseURL(urlStr)
+func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	if d == nil {
+		d = &nilDialer
+	}
+
+	challengeKey, err := generateChallengeKey()
 	if err != nil {
 		return nil, nil, err
 	}
 
-	hostPort, hostNoPort := hostPortNoPort(u)
-
-	if d == nil {
-		d = &Dialer{}
+	u, err := url.Parse(urlStr)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	switch u.Scheme {
+	case "ws":
+		u.Scheme = "http"
+	case "wss":
+		u.Scheme = "https"
+	default:
+		return nil, nil, errMalformedURL
+	}
+
+	if u.User != nil {
+		// User name and password are not allowed in websocket URIs.
+		return nil, nil, errMalformedURL
+	}
+
+	req := &http.Request{
+		Method:     "GET",
+		URL:        u,
+		Proto:      "HTTP/1.1",
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+		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 {
+		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
+	// method canonicalizes the header names.
+	req.Header["Upgrade"] = []string{"websocket"}
+	req.Header["Connection"] = []string{"Upgrade"}
+	req.Header["Sec-WebSocket-Key"] = []string{challengeKey}
+	req.Header["Sec-WebSocket-Version"] = []string{"13"}
+	if len(d.Subprotocols) > 0 {
+		req.Header["Sec-WebSocket-Protocol"] = []string{strings.Join(d.Subprotocols, ", ")}
+	}
+	for k, vs := range requestHeader {
+		switch {
+		case k == "Host":
+			if len(vs) > 0 {
+				req.Host = vs[0]
+			}
+		case k == "Upgrade" ||
+			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)
+		case k == "Sec-Websocket-Protocol":
+			req.Header["Sec-WebSocket-Protocol"] = vs
+		default:
+			req.Header[k] = vs
+		}
+	}
+
+	if d.EnableCompression {
+		req.Header["Sec-WebSocket-Extensions"] = []string{"permessage-deflate; server_no_context_takeover; client_no_context_takeover"}
 	}
 
-	var deadline time.Time
 	if d.HandshakeTimeout != 0 {
-		deadline = time.Now().Add(d.HandshakeTimeout)
+		var cancel func()
+		ctx, cancel = context.WithTimeout(ctx, d.HandshakeTimeout)
+		defer cancel()
 	}
 
-	netDial := d.NetDial
-	if netDial == nil {
-		netDialer := &net.Dialer{Deadline: deadline}
-		netDial = netDialer.Dial
+	// 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 {
+		netDialer := &net.Dialer{}
+		netDial = func(network, addr string) (net.Conn, error) {
+			return netDialer.DialContext(ctx, network, addr)
+		}
+	}
+
+	// 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
+		}
+	}
+
+	// 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", hostPort)
+	if trace != nil && trace.GotConn != nil {
+		trace.GotConn(httptrace.GotConnInfo{
+			Conn: netConn,
+		})
+	}
 	if err != nil {
 		return nil, nil, err
 	}
@@ -199,71 +304,92 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 	}()
 
-	if err := netConn.SetDeadline(deadline); err != nil {
-		return nil, nil, err
-	}
-
-	if u.Scheme == "wss" {
-		cfg := d.TLSClientConfig
-		if cfg == nil {
-			cfg = &tls.Config{ServerName: hostNoPort}
-		} else if cfg.ServerName == "" {
-			shallowCopy := *cfg
-			cfg = &shallowCopy
+	if u.Scheme == "https" {
+		cfg := cloneTLSConfig(d.TLSClientConfig)
+		if cfg.ServerName == "" {
 			cfg.ServerName = hostNoPort
 		}
 		tlsConn := tls.Client(netConn, cfg)
 		netConn = tlsConn
-		if err := tlsConn.Handshake(); err != nil {
+
+		var err error
+		if trace != nil {
+			err = doHandshakeWithTrace(trace, tlsConn, cfg)
+		} else {
+			err = doHandshake(tlsConn, cfg)
+		}
+
+		if err != nil {
 			return nil, nil, err
 		}
-		if !cfg.InsecureSkipVerify {
-			if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
-				return nil, nil, err
-			}
+	}
+
+	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()
 		}
 	}
 
-	if len(d.Subprotocols) > 0 {
-		h := http.Header{}
-		for k, v := range requestHeader {
-			h[k] = v
-		}
-		h.Set("Sec-Websocket-Protocol", strings.Join(d.Subprotocols, ", "))
-		requestHeader = h
-	}
-
-	if len(requestHeader["Host"]) > 0 {
-		// This can be used to supply a Host: header which is different from
-		// the dial address.
-		u.Host = requestHeader.Get("Host")
-
-		// Drop "Host" header
-		h := http.Header{}
-		for k, v := range requestHeader {
-			if k == "Host" {
-				continue
-			}
-			h[k] = v
-		}
-		requestHeader = h
-	}
-
-	conn, resp, err := NewClient(netConn, u, requestHeader, d.ReadBufferSize, d.WriteBufferSize)
-
+	resp, err := http.ReadResponse(conn.br, req)
 	if err != nil {
-		if err == ErrBadHandshake {
-			// Before closing the network connection on return from this
-			// function, slurp up some of the response to aid application
-			// debugging.
-			buf := make([]byte, 1024)
-			n, _ := io.ReadFull(resp.Body, buf)
-			resp.Body = ioutil.NopCloser(bytes.NewReader(buf[:n]))
-		}
-		return nil, resp, err
+		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") ||
+		resp.Header.Get("Sec-Websocket-Accept") != computeAcceptKey(challengeKey) {
+		// Before closing the network connection on return from this
+		// function, slurp up some of the response to aid application
+		// debugging.
+		buf := make([]byte, 1024)
+		n, _ := io.ReadFull(resp.Body, buf)
+		resp.Body = ioutil.NopCloser(bytes.NewReader(buf[:n]))
+		return nil, resp, ErrBadHandshake
+	}
+
+	for _, ext := range parseExtensions(resp.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")
+
 	netConn.SetDeadline(time.Time{})
 	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
+}