+
+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
+ a [Codec marshal](http://godoc.org/golang.org/x/net/websocket#Codec.Marshal)
+ function.
+3. The go.net io.Reader and io.Writer operate across WebSocket frame boundaries.
+ Read returns when the input buffer is full or a frame boundary is
+ encountered. Each call to Write sends a single frame message. The Gorilla
+ io.Reader and io.WriteCloser operate on a single WebSocket message.
+
diff --git a/vendor/github.com/gorilla/websocket/client.go b/vendor/github.com/gorilla/websocket/client.go
new file mode 100644
index 000000000..43a87c753
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/client.go
@@ -0,0 +1,392 @@
+// Copyright 2013 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"
+ "bytes"
+ "crypto/tls"
+ "encoding/base64"
+ "errors"
+ "io"
+ "io/ioutil"
+ "net"
+ "net/http"
+ "net/url"
+ "strings"
+ "time"
+)
+
+// ErrBadHandshake is returned when the server response to opening handshake is
+// 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
+// (Cookie). Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// 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) {
+ d := Dialer{
+ ReadBufferSize: readBufSize,
+ WriteBufferSize: writeBufSize,
+ NetDial: func(net, addr string) (net.Conn, error) {
+ return netConn, nil
+ },
+ }
+ return d.Dial(u.String(), requestHeader)
+}
+
+// A Dialer contains options for connecting to WebSocket server.
+type Dialer struct {
+ // NetDial specifies the dial function for creating TCP connections. If
+ // NetDial is nil, net.Dial is used.
+ NetDial func(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
+
+ // HandshakeTimeout specifies the duration for the handshake to complete.
+ HandshakeTimeout time.Duration
+
+ // 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
+
+ // 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")
+
+// 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
+}
+
+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 {
+ switch u.Scheme {
+ case "wss":
+ hostPort += ":443"
+ 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{
+ Proxy: http.ProxyFromEnvironment,
+}
+
+// Dial 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).
+//
+// 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) {
+
+ if d == nil {
+ d = &Dialer{
+ Proxy: http.ProxyFromEnvironment,
+ }
+ }
+
+ challengeKey, err := generateChallengeKey()
+ if err != nil {
+ return nil, nil, err
+ }
+
+ u, err := parseURL(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,
+ }
+
+ // 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)
+ default:
+ req.Header[k] = vs
+ }
+ }
+
+ 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
+ // Check wether the proxy method has been configured
+ if d.Proxy != nil {
+ proxyURL, err = d.Proxy(req)
+ }
+ if err != nil {
+ return nil, nil, err
+ }
+
+ var targetHostPort string
+ if proxyURL != nil {
+ targetHostPort, _ = hostPortNoPort(proxyURL)
+ } else {
+ targetHostPort = hostPort
+ }
+
+ var deadline time.Time
+ if d.HandshakeTimeout != 0 {
+ deadline = time.Now().Add(d.HandshakeTimeout)
+ }
+
+ netDial := d.NetDial
+ if netDial == nil {
+ netDialer := &net.Dialer{Deadline: deadline}
+ netDial = netDialer.Dial
+ }
+
+ netConn, err := netDial("tcp", targetHostPort)
+ if err != nil {
+ return nil, nil, err
+ }
+
+ defer func() {
+ if netConn != nil {
+ netConn.Close()
+ }
+ }()
+
+ 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 == "" {
+ cfg.ServerName = hostNoPort
+ }
+ tlsConn := tls.Client(netConn, cfg)
+ netConn = tlsConn
+ if err := tlsConn.Handshake(); 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)
+
+ if err := req.Write(netConn); err != nil {
+ return nil, nil, err
+ }
+
+ resp, err := http.ReadResponse(conn.br, req)
+ 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") ||
+ 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
+}
diff --git a/vendor/github.com/gorilla/websocket/client_clone.go b/vendor/github.com/gorilla/websocket/client_clone.go
new file mode 100644
index 000000000..4f0d94372
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/client_clone.go
@@ -0,0 +1,16 @@
+// Copyright 2013 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
+
+import "crypto/tls"
+
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+ if cfg == nil {
+ return &tls.Config{}
+ }
+ return cfg.Clone()
+}
diff --git a/vendor/github.com/gorilla/websocket/client_clone_legacy.go b/vendor/github.com/gorilla/websocket/client_clone_legacy.go
new file mode 100644
index 000000000..babb007fb
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/client_clone_legacy.go
@@ -0,0 +1,38 @@
+// Copyright 2013 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
+
+import "crypto/tls"
+
+// cloneTLSConfig clones all public fields except the fields
+// SessionTicketsDisabled and SessionTicketKey. This avoids copying the
+// sync.Mutex in the sync.Once and makes it safe to call cloneTLSConfig on a
+// config in active use.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+ if cfg == nil {
+ return &tls.Config{}
+ }
+ return &tls.Config{
+ Rand: cfg.Rand,
+ Time: cfg.Time,
+ Certificates: cfg.Certificates,
+ NameToCertificate: cfg.NameToCertificate,
+ GetCertificate: cfg.GetCertificate,
+ RootCAs: cfg.RootCAs,
+ NextProtos: cfg.NextProtos,
+ ServerName: cfg.ServerName,
+ ClientAuth: cfg.ClientAuth,
+ ClientCAs: cfg.ClientCAs,
+ InsecureSkipVerify: cfg.InsecureSkipVerify,
+ CipherSuites: cfg.CipherSuites,
+ PreferServerCipherSuites: cfg.PreferServerCipherSuites,
+ ClientSessionCache: cfg.ClientSessionCache,
+ MinVersion: cfg.MinVersion,
+ MaxVersion: cfg.MaxVersion,
+ CurvePreferences: cfg.CurvePreferences,
+ }
+}
diff --git a/vendor/github.com/gorilla/websocket/compression.go b/vendor/github.com/gorilla/websocket/compression.go
new file mode 100644
index 000000000..813ffb1e8
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/compression.go
@@ -0,0 +1,148 @@
+// 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 (
+ "compress/flate"
+ "errors"
+ "io"
+ "strings"
+ "sync"
+)
+
+const (
+ minCompressionLevel = -2 // flate.HuffmanOnly not defined in Go < 1.6
+ maxCompressionLevel = flate.BestCompression
+ defaultCompressionLevel = 1
+)
+
+var (
+ flateWriterPools [maxCompressionLevel - minCompressionLevel + 1]sync.Pool
+ flateReaderPool = sync.Pool{New: func() interface{} {
+ return flate.NewReader(nil)
+ }}
+)
+
+func decompressNoContextTakeover(r io.Reader) io.ReadCloser {
+ const tail =
+ // Add four bytes as specified in RFC
+ "\x00\x00\xff\xff" +
+ // Add final block to squelch unexpected EOF error from flate reader.
+ "\x01\x00\x00\xff\xff"
+
+ fr, _ := flateReaderPool.Get().(io.ReadCloser)
+ fr.(flate.Resetter).Reset(io.MultiReader(r, strings.NewReader(tail)), nil)
+ return &flateReadWrapper{fr}
+}
+
+func isValidCompressionLevel(level int) bool {
+ return minCompressionLevel <= level && level <= maxCompressionLevel
+}
+
+func compressNoContextTakeover(w io.WriteCloser, level int) io.WriteCloser {
+ p := &flateWriterPools[level-minCompressionLevel]
+ tw := &truncWriter{w: w}
+ fw, _ := p.Get().(*flate.Writer)
+ if fw == nil {
+ fw, _ = flate.NewWriter(tw, level)
+ } else {
+ fw.Reset(tw)
+ }
+ return &flateWriteWrapper{fw: fw, tw: tw, p: p}
+}
+
+// truncWriter is an io.Writer that writes all but the last four bytes of the
+// stream to another io.Writer.
+type truncWriter struct {
+ w io.WriteCloser
+ n int
+ p [4]byte
+}
+
+func (w *truncWriter) Write(p []byte) (int, error) {
+ n := 0
+
+ // fill buffer first for simplicity.
+ if w.n < len(w.p) {
+ n = copy(w.p[w.n:], p)
+ p = p[n:]
+ w.n += n
+ if len(p) == 0 {
+ return n, nil
+ }
+ }
+
+ m := len(p)
+ if m > len(w.p) {
+ m = len(w.p)
+ }
+
+ if nn, err := w.w.Write(w.p[:m]); err != nil {
+ return n + nn, err
+ }
+
+ copy(w.p[:], w.p[m:])
+ copy(w.p[len(w.p)-m:], p[len(p)-m:])
+ nn, err := w.w.Write(p[:len(p)-m])
+ return n + nn, err
+}
+
+type flateWriteWrapper struct {
+ fw *flate.Writer
+ tw *truncWriter
+ p *sync.Pool
+}
+
+func (w *flateWriteWrapper) Write(p []byte) (int, error) {
+ if w.fw == nil {
+ return 0, errWriteClosed
+ }
+ return w.fw.Write(p)
+}
+
+func (w *flateWriteWrapper) Close() error {
+ if w.fw == nil {
+ return errWriteClosed
+ }
+ err1 := w.fw.Flush()
+ w.p.Put(w.fw)
+ w.fw = nil
+ if w.tw.p != [4]byte{0, 0, 0xff, 0xff} {
+ return errors.New("websocket: internal error, unexpected bytes at end of flate stream")
+ }
+ err2 := w.tw.w.Close()
+ if err1 != nil {
+ return err1
+ }
+ return err2
+}
+
+type flateReadWrapper struct {
+ fr io.ReadCloser
+}
+
+func (r *flateReadWrapper) Read(p []byte) (int, error) {
+ if r.fr == nil {
+ return 0, io.ErrClosedPipe
+ }
+ n, err := r.fr.Read(p)
+ if err == io.EOF {
+ // Preemptively place the reader back in the pool. This helps with
+ // scenarios where the application does not call NextReader() soon after
+ // this final read.
+ r.Close()
+ }
+ return n, err
+}
+
+func (r *flateReadWrapper) Close() error {
+ if r.fr == nil {
+ return io.ErrClosedPipe
+ }
+ err := r.fr.Close()
+ flateReaderPool.Put(r.fr)
+ r.fr = nil
+ return err
+}
diff --git a/vendor/github.com/gorilla/websocket/conn.go b/vendor/github.com/gorilla/websocket/conn.go
new file mode 100644
index 000000000..97e1dbacb
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/conn.go
@@ -0,0 +1,1149 @@
+// Copyright 2013 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/binary"
+ "errors"
+ "io"
+ "io/ioutil"
+ "math/rand"
+ "net"
+ "strconv"
+ "sync"
+ "time"
+ "unicode/utf8"
+)
+
+const (
+ // Frame header byte 0 bits from Section 5.2 of RFC 6455
+ finalBit = 1 << 7
+ rsv1Bit = 1 << 6
+ rsv2Bit = 1 << 5
+ rsv3Bit = 1 << 4
+
+ // Frame header byte 1 bits from Section 5.2 of RFC 6455
+ maskBit = 1 << 7
+
+ maxFrameHeaderSize = 2 + 8 + 4 // Fixed header + length + mask
+ maxControlFramePayloadSize = 125
+
+ writeWait = time.Second
+
+ defaultReadBufferSize = 4096
+ defaultWriteBufferSize = 4096
+
+ continuationFrame = 0
+ noFrame = -1
+)
+
+// Close codes defined in RFC 6455, section 11.7.
+const (
+ CloseNormalClosure = 1000
+ CloseGoingAway = 1001
+ CloseProtocolError = 1002
+ CloseUnsupportedData = 1003
+ CloseNoStatusReceived = 1005
+ CloseAbnormalClosure = 1006
+ CloseInvalidFramePayloadData = 1007
+ ClosePolicyViolation = 1008
+ CloseMessageTooBig = 1009
+ CloseMandatoryExtension = 1010
+ CloseInternalServerErr = 1011
+ CloseServiceRestart = 1012
+ CloseTryAgainLater = 1013
+ CloseTLSHandshake = 1015
+)
+
+// The message types are defined in RFC 6455, section 11.8.
+const (
+ // TextMessage denotes a text data message. The text message payload is
+ // interpreted as UTF-8 encoded text data.
+ TextMessage = 1
+
+ // BinaryMessage denotes a binary data message.
+ BinaryMessage = 2
+
+ // CloseMessage denotes a close control message. The optional message
+ // payload contains a numeric code and text. Use the FormatCloseMessage
+ // function to format a close message payload.
+ CloseMessage = 8
+
+ // PingMessage denotes a ping control message. The optional message payload
+ // is UTF-8 encoded text.
+ PingMessage = 9
+
+ // PongMessage denotes a ping control message. The optional message payload
+ // is UTF-8 encoded text.
+ PongMessage = 10
+)
+
+// ErrCloseSent is returned when the application writes a message to the
+// connection after sending a close message.
+var ErrCloseSent = errors.New("websocket: close sent")
+
+// ErrReadLimit is returned when reading a message that is larger than the
+// read limit set for the connection.
+var ErrReadLimit = errors.New("websocket: read limit exceeded")
+
+// netError satisfies the net Error interface.
+type netError struct {
+ msg string
+ temporary bool
+ timeout bool
+}
+
+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.
+type CloseError struct {
+
+ // Code is defined in RFC 6455, section 11.7.
+ Code int
+
+ // Text is the optional text payload.
+ Text string
+}
+
+func (e *CloseError) Error() string {
+ s := []byte("websocket: close ")
+ s = strconv.AppendInt(s, int64(e.Code), 10)
+ switch e.Code {
+ case CloseNormalClosure:
+ s = append(s, " (normal)"...)
+ case CloseGoingAway:
+ s = append(s, " (going away)"...)
+ case CloseProtocolError:
+ s = append(s, " (protocol error)"...)
+ case CloseUnsupportedData:
+ s = append(s, " (unsupported data)"...)
+ case CloseNoStatusReceived:
+ s = append(s, " (no status)"...)
+ case CloseAbnormalClosure:
+ s = append(s, " (abnormal closure)"...)
+ case CloseInvalidFramePayloadData:
+ s = append(s, " (invalid payload data)"...)
+ case ClosePolicyViolation:
+ s = append(s, " (policy violation)"...)
+ case CloseMessageTooBig:
+ s = append(s, " (message too big)"...)
+ case CloseMandatoryExtension:
+ s = append(s, " (mandatory extension missing)"...)
+ case CloseInternalServerErr:
+ s = append(s, " (internal server error)"...)
+ case CloseTLSHandshake:
+ s = append(s, " (TLS handshake error)"...)
+ }
+ if e.Text != "" {
+ s = append(s, ": "...)
+ s = append(s, e.Text...)
+ }
+ return string(s)
+}
+
+// IsCloseError returns boolean indicating whether the error is a *CloseError
+// with one of the specified codes.
+func IsCloseError(err error, codes ...int) bool {
+ if e, ok := err.(*CloseError); ok {
+ for _, code := range codes {
+ if e.Code == code {
+ return true
+ }
+ }
+ }
+ return false
+}
+
+// IsUnexpectedCloseError returns boolean indicating whether the error is a
+// *CloseError with a code not in the list of expected codes.
+func IsUnexpectedCloseError(err error, expectedCodes ...int) bool {
+ if e, ok := err.(*CloseError); ok {
+ for _, code := range expectedCodes {
+ if e.Code == code {
+ return false
+ }
+ }
+ return true
+ }
+ return false
+}
+
+var (
+ errWriteTimeout = &netError{msg: "websocket: write timeout", timeout: true, temporary: true}
+ errUnexpectedEOF = &CloseError{Code: CloseAbnormalClosure, Text: io.ErrUnexpectedEOF.Error()}
+ errBadWriteOpCode = errors.New("websocket: bad write message type")
+ errWriteClosed = errors.New("websocket: write closed")
+ errInvalidControlFrame = errors.New("websocket: invalid control frame")
+)
+
+func newMaskKey() [4]byte {
+ n := rand.Uint32()
+ return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
+}
+
+func hideTempErr(err error) error {
+ if e, ok := err.(net.Error); ok && e.Temporary() {
+ err = &netError{msg: e.Error(), timeout: e.Timeout()}
+ }
+ return err
+}
+
+func isControl(frameType int) bool {
+ return frameType == CloseMessage || frameType == PingMessage || frameType == PongMessage
+}
+
+func isData(frameType int) bool {
+ return frameType == TextMessage || frameType == BinaryMessage
+}
+
+var validReceivedCloseCodes = map[int]bool{
+ // see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number
+
+ CloseNormalClosure: true,
+ CloseGoingAway: true,
+ CloseProtocolError: true,
+ CloseUnsupportedData: true,
+ CloseNoStatusReceived: false,
+ CloseAbnormalClosure: false,
+ CloseInvalidFramePayloadData: true,
+ ClosePolicyViolation: true,
+ CloseMessageTooBig: true,
+ CloseMandatoryExtension: true,
+ CloseInternalServerErr: true,
+ CloseServiceRestart: true,
+ CloseTryAgainLater: true,
+ CloseTLSHandshake: false,
+}
+
+func isValidReceivedCloseCode(code int) bool {
+ return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
+}
+
+// The Conn type represents a WebSocket connection.
+type Conn struct {
+ conn net.Conn
+ isServer bool
+ subprotocol string
+
+ // Write fields
+ mu chan bool // used as mutex to protect write to conn
+ writeBuf []byte // frame is constructed in this buffer.
+ writeDeadline time.Time
+ writer io.WriteCloser // the current writer returned to the application
+ isWriting bool // for best-effort concurrent write detection
+
+ writeErrMu sync.Mutex
+ writeErr error
+
+ enableWriteCompression bool
+ compressionLevel int
+ newCompressionWriter func(io.WriteCloser, int) io.WriteCloser
+
+ // Read fields
+ reader io.ReadCloser // the current reader returned to the application
+ readErr error
+ br *bufio.Reader
+ readRemaining int64 // bytes remaining in current frame.
+ readFinal bool // true the current message has more frames.
+ readLength int64 // Message size.
+ readLimit int64 // Maximum message size.
+ readMaskPos int
+ readMaskKey [4]byte
+ handlePong func(string) error
+ handlePing func(string) error
+ handleClose func(int, string) error
+ readErrCount int
+ messageReader *messageReader // the current low-level reader
+
+ readDecompress bool // whether last read frame had RSV1 set
+ 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
+
+ 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 {
+ 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 writeBuf == nil {
+ if writeBufferSize == 0 {
+ writeBufferSize = defaultWriteBufferSize
+ }
+ writeBuf = make([]byte, writeBufferSize+maxFrameHeaderSize)
+ }
+
+ c := &Conn{
+ isServer: isServer,
+ br: br,
+ conn: conn,
+ mu: mu,
+ readFinal: true,
+ writeBuf: writeBuf,
+ enableWriteCompression: true,
+ compressionLevel: defaultCompressionLevel,
+ }
+ c.SetCloseHandler(nil)
+ c.SetPingHandler(nil)
+ c.SetPongHandler(nil)
+ return c
+}
+
+// Subprotocol returns the negotiated protocol for the connection.
+func (c *Conn) Subprotocol() string {
+ return c.subprotocol
+}
+
+// Close closes the underlying network connection without sending or waiting for a close frame.
+func (c *Conn) Close() error {
+ return c.conn.Close()
+}
+
+// LocalAddr returns the local network address.
+func (c *Conn) LocalAddr() net.Addr {
+ return c.conn.LocalAddr()
+}
+
+// RemoteAddr returns the remote network address.
+func (c *Conn) RemoteAddr() net.Addr {
+ return c.conn.RemoteAddr()
+}
+
+// Write methods
+
+func (c *Conn) writeFatal(err error) error {
+ err = hideTempErr(err)
+ c.writeErrMu.Lock()
+ if c.writeErr == nil {
+ c.writeErr = err
+ }
+ c.writeErrMu.Unlock()
+ return err
+}
+
+func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
+ <-c.mu
+ defer func() { c.mu <- true }()
+
+ c.writeErrMu.Lock()
+ err := c.writeErr
+ c.writeErrMu.Unlock()
+ if err != nil {
+ return err
+ }
+
+ 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 frameType == CloseMessage {
+ c.writeFatal(ErrCloseSent)
+ }
+ return nil
+}
+
+// WriteControl writes a control message with the given deadline. The allowed
+// message types are CloseMessage, PingMessage and PongMessage.
+func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) error {
+ if !isControl(messageType) {
+ return errBadWriteOpCode
+ }
+ if len(data) > maxControlFramePayloadSize {
+ return errInvalidControlFrame
+ }
+
+ b0 := byte(messageType) | finalBit
+ b1 := byte(len(data))
+ if !c.isServer {
+ b1 |= maskBit
+ }
+
+ buf := make([]byte, 0, maxFrameHeaderSize+maxControlFramePayloadSize)
+ buf = append(buf, b0, b1)
+
+ if c.isServer {
+ buf = append(buf, data...)
+ } else {
+ key := newMaskKey()
+ buf = append(buf, key[:]...)
+ buf = append(buf, data...)
+ maskBytes(key, 0, buf[6:])
+ }
+
+ d := time.Hour * 1000
+ if !deadline.IsZero() {
+ d = deadline.Sub(time.Now())
+ if d < 0 {
+ return errWriteTimeout
+ }
+ }
+
+ timer := time.NewTimer(d)
+ select {
+ case <-c.mu:
+ timer.Stop()
+ case <-timer.C:
+ return errWriteTimeout
+ }
+ defer func() { c.mu <- true }()
+
+ c.writeErrMu.Lock()
+ err := c.writeErr
+ c.writeErrMu.Unlock()
+ if err != nil {
+ return err
+ }
+
+ c.conn.SetWriteDeadline(deadline)
+ _, err = c.conn.Write(buf)
+ if err != nil {
+ return c.writeFatal(err)
+ }
+ if messageType == CloseMessage {
+ c.writeFatal(ErrCloseSent)
+ }
+ return err
+}
+
+func (c *Conn) prepWrite(messageType int) error {
+ // Close previous writer if not already closed by the application. It's
+ // probably better to return an error in this situation, but we cannot
+ // change this without breaking existing applications.
+ if c.writer != nil {
+ c.writer.Close()
+ c.writer = nil
+ }
+
+ if !isControl(messageType) && !isData(messageType) {
+ return errBadWriteOpCode
+ }
+
+ c.writeErrMu.Lock()
+ err := c.writeErr
+ c.writeErrMu.Unlock()
+ return err
+}
+
+// NextWriter returns a writer for the next message to send. The writer's Close
+// method flushes the complete message to the network.
+//
+// There can be at most one open writer on a connection. NextWriter closes the
+// previous writer if the application has not already done so.
+func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
+ if err := c.prepWrite(messageType); err != nil {
+ return nil, err
+ }
+
+ mw := &messageWriter{
+ c: c,
+ frameType: messageType,
+ pos: maxFrameHeaderSize,
+ }
+ c.writer = mw
+ if c.newCompressionWriter != nil && c.enableWriteCompression && isData(messageType) {
+ w := c.newCompressionWriter(c.writer, c.compressionLevel)
+ mw.compress = true
+ c.writer = w
+ }
+ return c.writer, nil
+}
+
+type messageWriter struct {
+ c *Conn
+ compress bool // whether next call to flushFrame should set RSV1
+ pos int // end of data in writeBuf.
+ frameType int // type of the current frame.
+ err error
+}
+
+func (w *messageWriter) fatal(err error) error {
+ if w.err != nil {
+ w.err = err
+ w.c.writer = nil
+ }
+ return err
+}
+
+// flushFrame writes buffered data and extra as a frame to the network. The
+// final argument indicates that this is the last frame in the message.
+func (w *messageWriter) flushFrame(final bool, extra []byte) error {
+ c := w.c
+ length := w.pos - maxFrameHeaderSize + len(extra)
+
+ // Check for invalid control frames.
+ if isControl(w.frameType) &&
+ (!final || length > maxControlFramePayloadSize) {
+ return w.fatal(errInvalidControlFrame)
+ }
+
+ b0 := byte(w.frameType)
+ if final {
+ b0 |= finalBit
+ }
+ if w.compress {
+ b0 |= rsv1Bit
+ }
+ w.compress = false
+
+ b1 := byte(0)
+ if !c.isServer {
+ b1 |= maskBit
+ }
+
+ // Assume that the frame starts at beginning of c.writeBuf.
+ framePos := 0
+ if c.isServer {
+ // Adjust up if mask not included in the header.
+ framePos = 4
+ }
+
+ switch {
+ case length >= 65536:
+ c.writeBuf[framePos] = b0
+ c.writeBuf[framePos+1] = b1 | 127
+ binary.BigEndian.PutUint64(c.writeBuf[framePos+2:], uint64(length))
+ case length > 125:
+ framePos += 6
+ c.writeBuf[framePos] = b0
+ c.writeBuf[framePos+1] = b1 | 126
+ binary.BigEndian.PutUint16(c.writeBuf[framePos+2:], uint16(length))
+ default:
+ framePos += 8
+ c.writeBuf[framePos] = b0
+ c.writeBuf[framePos+1] = b1 | byte(length)
+ }
+
+ if !c.isServer {
+ key := newMaskKey()
+ copy(c.writeBuf[maxFrameHeaderSize-4:], key[:])
+ maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:w.pos])
+ if len(extra) > 0 {
+ return c.writeFatal(errors.New("websocket: internal error, extra used in client mode"))
+ }
+ }
+
+ // Write the buffers to the connection with best-effort detection of
+ // concurrent writes. See the concurrency section in the package
+ // documentation for more info.
+
+ if c.isWriting {
+ panic("concurrent write to websocket connection")
+ }
+ c.isWriting = true
+
+ err := c.write(w.frameType, c.writeDeadline, c.writeBuf[framePos:w.pos], extra)
+
+ if !c.isWriting {
+ panic("concurrent write to websocket connection")
+ }
+ c.isWriting = false
+
+ if err != nil {
+ return w.fatal(err)
+ }
+
+ if final {
+ c.writer = nil
+ return nil
+ }
+
+ // Setup for next frame.
+ w.pos = maxFrameHeaderSize
+ w.frameType = continuationFrame
+ return nil
+}
+
+func (w *messageWriter) ncopy(max int) (int, error) {
+ n := len(w.c.writeBuf) - w.pos
+ if n <= 0 {
+ if err := w.flushFrame(false, nil); err != nil {
+ return 0, err
+ }
+ n = len(w.c.writeBuf) - w.pos
+ }
+ if n > max {
+ n = max
+ }
+ return n, nil
+}
+
+func (w *messageWriter) Write(p []byte) (int, error) {
+ if w.err != nil {
+ return 0, w.err
+ }
+
+ if len(p) > 2*len(w.c.writeBuf) && w.c.isServer {
+ // Don't buffer large messages.
+ err := w.flushFrame(false, p)
+ if err != nil {
+ return 0, err
+ }
+ return len(p), nil
+ }
+
+ nn := len(p)
+ for len(p) > 0 {
+ n, err := w.ncopy(len(p))
+ if err != nil {
+ return 0, err
+ }
+ copy(w.c.writeBuf[w.pos:], p[:n])
+ w.pos += n
+ p = p[n:]
+ }
+ return nn, nil
+}
+
+func (w *messageWriter) WriteString(p string) (int, error) {
+ if w.err != nil {
+ return 0, w.err
+ }
+
+ nn := len(p)
+ for len(p) > 0 {
+ n, err := w.ncopy(len(p))
+ if err != nil {
+ return 0, err
+ }
+ copy(w.c.writeBuf[w.pos:], p[:n])
+ w.pos += n
+ p = p[n:]
+ }
+ return nn, nil
+}
+
+func (w *messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
+ if w.err != nil {
+ return 0, w.err
+ }
+ for {
+ if w.pos == len(w.c.writeBuf) {
+ err = w.flushFrame(false, nil)
+ if err != nil {
+ break
+ }
+ }
+ var n int
+ n, err = r.Read(w.c.writeBuf[w.pos:])
+ w.pos += n
+ nn += int64(n)
+ if err != nil {
+ if err == io.EOF {
+ err = nil
+ }
+ break
+ }
+ }
+ return nn, err
+}
+
+func (w *messageWriter) Close() error {
+ if w.err != nil {
+ return w.err
+ }
+ if err := w.flushFrame(true, nil); err != nil {
+ return err
+ }
+ w.err = errWriteClosed
+ return nil
+}
+
+// WritePreparedMessage writes prepared message into connection.
+func (c *Conn) WritePreparedMessage(pm *PreparedMessage) error {
+ frameType, frameData, err := pm.frame(prepareKey{
+ isServer: c.isServer,
+ compress: c.newCompressionWriter != nil && c.enableWriteCompression && isData(pm.messageType),
+ compressionLevel: c.compressionLevel,
+ })
+ if err != nil {
+ return err
+ }
+ if c.isWriting {
+ panic("concurrent write to websocket connection")
+ }
+ c.isWriting = true
+ err = c.write(frameType, c.writeDeadline, frameData, nil)
+ if !c.isWriting {
+ panic("concurrent write to websocket connection")
+ }
+ c.isWriting = false
+ return err
+}
+
+// WriteMessage is a helper method for getting a writer using NextWriter,
+// writing the message and closing the writer.
+func (c *Conn) WriteMessage(messageType int, data []byte) error {
+
+ if c.isServer && (c.newCompressionWriter == nil || !c.enableWriteCompression) {
+ // Fast path with no allocations and single frame.
+
+ if err := c.prepWrite(messageType); err != nil {
+ return err
+ }
+ mw := messageWriter{c: c, frameType: messageType, pos: maxFrameHeaderSize}
+ n := copy(c.writeBuf[mw.pos:], data)
+ mw.pos += n
+ data = data[n:]
+ return mw.flushFrame(true, data)
+ }
+
+ w, err := c.NextWriter(messageType)
+ if err != nil {
+ return err
+ }
+ if _, err = w.Write(data); err != nil {
+ return err
+ }
+ return w.Close()
+}
+
+// SetWriteDeadline sets the write deadline on the underlying network
+// connection. After a write has timed out, the websocket state is corrupt and
+// all future writes will return an error. A zero value for t means writes will
+// not time out.
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+ c.writeDeadline = t
+ return nil
+}
+
+// Read methods
+
+func (c *Conn) advanceFrame() (int, error) {
+
+ // 1. Skip remainder of previous frame.
+
+ if c.readRemaining > 0 {
+ if _, err := io.CopyN(ioutil.Discard, c.br, c.readRemaining); err != nil {
+ return noFrame, err
+ }
+ }
+
+ // 2. Read and parse first two bytes of frame header.
+
+ p, err := c.read(2)
+ if err != nil {
+ return noFrame, err
+ }
+
+ final := p[0]&finalBit != 0
+ frameType := int(p[0] & 0xf)
+ mask := p[1]&maskBit != 0
+ c.readRemaining = int64(p[1] & 0x7f)
+
+ c.readDecompress = false
+ if c.newDecompressionReader != nil && (p[0]&rsv1Bit) != 0 {
+ c.readDecompress = true
+ p[0] &^= rsv1Bit
+ }
+
+ if rsv := p[0] & (rsv1Bit | rsv2Bit | rsv3Bit); rsv != 0 {
+ return noFrame, c.handleProtocolError("unexpected reserved bits 0x" + strconv.FormatInt(int64(rsv), 16))
+ }
+
+ switch frameType {
+ case CloseMessage, PingMessage, PongMessage:
+ if c.readRemaining > maxControlFramePayloadSize {
+ return noFrame, c.handleProtocolError("control frame length > 125")
+ }
+ if !final {
+ return noFrame, c.handleProtocolError("control frame not final")
+ }
+ case TextMessage, BinaryMessage:
+ if !c.readFinal {
+ return noFrame, c.handleProtocolError("message start before final message frame")
+ }
+ c.readFinal = final
+ case continuationFrame:
+ if c.readFinal {
+ return noFrame, c.handleProtocolError("continuation after final message frame")
+ }
+ c.readFinal = final
+ default:
+ return noFrame, c.handleProtocolError("unknown opcode " + strconv.Itoa(frameType))
+ }
+
+ // 3. Read and parse frame length.
+
+ switch c.readRemaining {
+ case 126:
+ p, err := c.read(2)
+ if err != nil {
+ return noFrame, err
+ }
+ c.readRemaining = int64(binary.BigEndian.Uint16(p))
+ case 127:
+ p, err := c.read(8)
+ if err != nil {
+ return noFrame, err
+ }
+ c.readRemaining = int64(binary.BigEndian.Uint64(p))
+ }
+
+ // 4. Handle frame masking.
+
+ if mask != c.isServer {
+ return noFrame, c.handleProtocolError("incorrect mask flag")
+ }
+
+ if mask {
+ c.readMaskPos = 0
+ p, err := c.read(len(c.readMaskKey))
+ if err != nil {
+ return noFrame, err
+ }
+ copy(c.readMaskKey[:], p)
+ }
+
+ // 5. For text and binary messages, enforce read limit and return.
+
+ if frameType == continuationFrame || frameType == TextMessage || frameType == BinaryMessage {
+
+ c.readLength += c.readRemaining
+ if c.readLimit > 0 && c.readLength > c.readLimit {
+ c.WriteControl(CloseMessage, FormatCloseMessage(CloseMessageTooBig, ""), time.Now().Add(writeWait))
+ return noFrame, ErrReadLimit
+ }
+
+ return frameType, nil
+ }
+
+ // 6. Read control frame payload.
+
+ var payload []byte
+ if c.readRemaining > 0 {
+ payload, err = c.read(int(c.readRemaining))
+ c.readRemaining = 0
+ if err != nil {
+ return noFrame, err
+ }
+ if c.isServer {
+ maskBytes(c.readMaskKey, 0, payload)
+ }
+ }
+
+ // 7. Process control frame payload.
+
+ switch frameType {
+ case PongMessage:
+ if err := c.handlePong(string(payload)); err != nil {
+ return noFrame, err
+ }
+ case PingMessage:
+ if err := c.handlePing(string(payload)); err != nil {
+ return noFrame, err
+ }
+ case CloseMessage:
+ closeCode := CloseNoStatusReceived
+ closeText := ""
+ if len(payload) >= 2 {
+ closeCode = int(binary.BigEndian.Uint16(payload))
+ if !isValidReceivedCloseCode(closeCode) {
+ return noFrame, c.handleProtocolError("invalid close code")
+ }
+ closeText = string(payload[2:])
+ if !utf8.ValidString(closeText) {
+ return noFrame, c.handleProtocolError("invalid utf8 payload in close frame")
+ }
+ }
+ if err := c.handleClose(closeCode, closeText); err != nil {
+ return noFrame, err
+ }
+ return noFrame, &CloseError{Code: closeCode, Text: closeText}
+ }
+
+ return frameType, nil
+}
+
+func (c *Conn) handleProtocolError(message string) error {
+ c.WriteControl(CloseMessage, FormatCloseMessage(CloseProtocolError, message), time.Now().Add(writeWait))
+ return errors.New("websocket: " + message)
+}
+
+// NextReader returns the next data message received from the peer. The
+// returned messageType is either TextMessage or BinaryMessage.
+//
+// There can be at most one open reader on a connection. NextReader discards
+// the previous message if the application has not already consumed it.
+//
+// Applications must break out of the application's read loop when this method
+// returns a non-nil error value. Errors returned from this method are
+// permanent. Once this method returns a non-nil error, all subsequent calls to
+// this method return the same error.
+func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
+ // Close previous reader, only relevant for decompression.
+ if c.reader != nil {
+ c.reader.Close()
+ c.reader = nil
+ }
+
+ c.messageReader = nil
+ c.readLength = 0
+
+ for c.readErr == nil {
+ frameType, err := c.advanceFrame()
+ if err != nil {
+ c.readErr = hideTempErr(err)
+ break
+ }
+ if frameType == TextMessage || frameType == BinaryMessage {
+ c.messageReader = &messageReader{c}
+ c.reader = c.messageReader
+ if c.readDecompress {
+ c.reader = c.newDecompressionReader(c.reader)
+ }
+ return frameType, c.reader, nil
+ }
+ }
+
+ // Applications that do handle the error returned from this method spin in
+ // tight loop on connection failure. To help application developers detect
+ // this error, panic on repeated reads to the failed connection.
+ c.readErrCount++
+ if c.readErrCount >= 1000 {
+ panic("repeated read on failed websocket connection")
+ }
+
+ return noFrame, nil, c.readErr
+}
+
+type messageReader struct{ c *Conn }
+
+func (r *messageReader) Read(b []byte) (int, error) {
+ c := r.c
+ if c.messageReader != r {
+ return 0, io.EOF
+ }
+
+ for c.readErr == nil {
+
+ if c.readRemaining > 0 {
+ if int64(len(b)) > c.readRemaining {
+ b = b[:c.readRemaining]
+ }
+ n, err := c.br.Read(b)
+ c.readErr = hideTempErr(err)
+ if c.isServer {
+ c.readMaskPos = maskBytes(c.readMaskKey, c.readMaskPos, b[:n])
+ }
+ c.readRemaining -= int64(n)
+ if c.readRemaining > 0 && c.readErr == io.EOF {
+ c.readErr = errUnexpectedEOF
+ }
+ return n, c.readErr
+ }
+
+ if c.readFinal {
+ c.messageReader = nil
+ return 0, io.EOF
+ }
+
+ frameType, err := c.advanceFrame()
+ switch {
+ case err != nil:
+ c.readErr = hideTempErr(err)
+ case frameType == TextMessage || frameType == BinaryMessage:
+ c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader")
+ }
+ }
+
+ err := c.readErr
+ if err == io.EOF && c.messageReader == r {
+ err = errUnexpectedEOF
+ }
+ return 0, err
+}
+
+func (r *messageReader) Close() error {
+ return nil
+}
+
+// ReadMessage is a helper method for getting a reader using NextReader and
+// reading from that reader to a buffer.
+func (c *Conn) ReadMessage() (messageType int, p []byte, err error) {
+ var r io.Reader
+ messageType, r, err = c.NextReader()
+ if err != nil {
+ return messageType, nil, err
+ }
+ p, err = ioutil.ReadAll(r)
+ return messageType, p, err
+}
+
+// SetReadDeadline sets the read deadline on the underlying network connection.
+// After a read has timed out, the websocket connection state is corrupt and
+// all future reads will return an error. A zero value for t means reads will
+// not time out.
+func (c *Conn) SetReadDeadline(t time.Time) error {
+ return c.conn.SetReadDeadline(t)
+}
+
+// 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
+// and returns ErrReadLimit to the application.
+func (c *Conn) SetReadLimit(limit int64) {
+ c.readLimit = limit
+}
+
+// CloseHandler returns the current close handler
+func (c *Conn) CloseHandler() func(code int, text string) error {
+ return c.handleClose
+}
+
+// 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.
+//
+// The application must read the connection to process close messages as
+// described in the section on Control Frames above.
+//
+// The connection read methods return a CloseError when a close frame 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
+// 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, "")
+ }
+ c.WriteControl(CloseMessage, message, time.Now().Add(writeWait))
+ return nil
+ }
+ }
+ c.handleClose = h
+}
+
+// PingHandler returns the current ping handler
+func (c *Conn) PingHandler() func(appData string) error {
+ return c.handlePing
+}
+
+// SetPingHandler sets the handler for ping messages received from the peer.
+// The appData argument to h is the PING frame 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.
+func (c *Conn) SetPingHandler(h func(appData string) error) {
+ if h == nil {
+ h = func(message string) error {
+ err := c.WriteControl(PongMessage, []byte(message), time.Now().Add(writeWait))
+ if err == ErrCloseSent {
+ return nil
+ } else if e, ok := err.(net.Error); ok && e.Temporary() {
+ return nil
+ }
+ return err
+ }
+ }
+ c.handlePing = h
+}
+
+// PongHandler returns the current pong handler
+func (c *Conn) PongHandler() func(appData string) error {
+ return c.handlePong
+}
+
+// SetPongHandler sets the handler for pong messages received from the peer.
+// The appData argument to h is the PONG frame 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.
+func (c *Conn) SetPongHandler(h func(appData string) error) {
+ if h == nil {
+ h = func(string) error { return nil }
+ }
+ c.handlePong = h
+}
+
+// UnderlyingConn returns the internal net.Conn. This can be used to further
+// modifications to connection specific flags.
+func (c *Conn) UnderlyingConn() net.Conn {
+ return c.conn
+}
+
+// EnableWriteCompression enables and disables write compression of
+// subsequent text and binary messages. This function is a noop if
+// compression was not negotiated with the peer.
+func (c *Conn) EnableWriteCompression(enable bool) {
+ c.enableWriteCompression = enable
+}
+
+// SetCompressionLevel sets the flate compression level for subsequent text and
+// binary messages. This function is a noop if compression was not negotiated
+// with the peer. See the compress/flate package for a description of
+// compression levels.
+func (c *Conn) SetCompressionLevel(level int) error {
+ if !isValidCompressionLevel(level) {
+ return errors.New("websocket: invalid compression level")
+ }
+ c.compressionLevel = level
+ return nil
+}
+
+// FormatCloseMessage formats closeCode and text as a WebSocket close message.
+func FormatCloseMessage(closeCode int, text string) []byte {
+ buf := make([]byte, 2+len(text))
+ binary.BigEndian.PutUint16(buf, uint16(closeCode))
+ copy(buf[2:], text)
+ return buf
+}
diff --git a/vendor/github.com/gorilla/websocket/conn_read.go b/vendor/github.com/gorilla/websocket/conn_read.go
new file mode 100644
index 000000000..1ea15059e
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/conn_read.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 go1.5
+
+package websocket
+
+import "io"
+
+func (c *Conn) read(n int) ([]byte, error) {
+ p, err := c.br.Peek(n)
+ if err == io.EOF {
+ err = errUnexpectedEOF
+ }
+ c.br.Discard(len(p))
+ return p, err
+}
diff --git a/vendor/github.com/gorilla/websocket/conn_read_legacy.go b/vendor/github.com/gorilla/websocket/conn_read_legacy.go
new file mode 100644
index 000000000..018541cf6
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/conn_read_legacy.go
@@ -0,0 +1,21 @@
+// 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/doc.go b/vendor/github.com/gorilla/websocket/doc.go
new file mode 100644
index 000000000..e291a952c
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/doc.go
@@ -0,0 +1,180 @@
+// Copyright 2013 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 implements the WebSocket protocol defined in RFC 6455.
+//
+// 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:
+//
+// var upgrader = websocket.Upgrader{
+// ReadBufferSize: 1024,
+// WriteBufferSize: 1024,
+// }
+//
+// func handler(w http.ResponseWriter, r *http.Request) {
+// conn, err := upgrader.Upgrade(w, r, nil)
+// if err != nil {
+// log.Println(err)
+// return
+// }
+// ... Use conn to send and receive messages.
+// }
+//
+// Call the connection's WriteMessage and ReadMessage methods to send and
+// receive messages as a slice of bytes. This snippet of code shows how to echo
+// messages using these methods:
+//
+// for {
+// messageType, p, err := conn.ReadMessage()
+// if err != nil {
+// return
+// }
+// if err = conn.WriteMessage(messageType, p); err != nil {
+// return err
+// }
+// }
+//
+// In above snippet of code, p is a []byte and messageType is an int with value
+// websocket.BinaryMessage or websocket.TextMessage.
+//
+// An application can also send and receive messages using the io.WriteCloser
+// and io.Reader interfaces. To send a message, call the connection NextWriter
+// method to get an io.WriteCloser, write the message to the writer and close
+// the writer when done. To receive a message, call the connection NextReader
+// method to get an io.Reader and read until io.EOF is returned. This snippet
+// shows how to echo messages using the NextWriter and NextReader methods:
+//
+// for {
+// messageType, r, err := conn.NextReader()
+// if err != nil {
+// return
+// }
+// w, err := conn.NextWriter(messageType)
+// if err != nil {
+// return err
+// }
+// if _, err := io.Copy(w, r); err != nil {
+// return err
+// }
+// if err := w.Close(); err != nil {
+// return err
+// }
+// }
+//
+// Data Messages
+//
+// The WebSocket protocol distinguishes between text and binary data messages.
+// Text messages are interpreted as UTF-8 encoded text. The interpretation of
+// binary messages is left to the application.
+//
+// This package uses the TextMessage and BinaryMessage integer constants to
+// identify the two data message types. The ReadMessage and NextReader methods
+// return the type of the received message. The messageType argument to the
+// WriteMessage and NextWriter methods specifies the type of a sent message.
+//
+// It is the application's responsibility to ensure that text messages are
+// valid UTF-8 encoded text.
+//
+// Control Messages
+//
+// The WebSocket protocol defines three types of control messages: close, ping
+// 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 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.
+//
+// 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.
+//
+// The application must read the connection to process ping, pong and close
+// 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:
+//
+// func readLoop(c *websocket.Conn) {
+// for {
+// if _, _, err := c.NextReader(); err != nil {
+// c.Close()
+// break
+// }
+// }
+// }
+//
+// Concurrency
+//
+// Connections support one concurrent reader and one concurrent writer.
+//
+// Applications are responsible for ensuring that no more than one goroutine
+// calls the write methods (NextWriter, SetWriteDeadline, WriteMessage,
+// WriteJSON, EnableWriteCompression, SetCompressionLevel) concurrently and
+// that no more than one goroutine calls the read methods (NextReader,
+// SetReadDeadline, ReadMessage, ReadJSON, SetPongHandler, SetPingHandler)
+// concurrently.
+//
+// The Close and WriteControl methods can be called concurrently with all other
+// methods.
+//
+// Origin Considerations
+//
+// Web browsers allow Javascript applications to open a WebSocket connection to
+// any host. It's up to the server to enforce an origin policy using the Origin
+// request header sent by the browser.
+//
+// The Upgrader calls the function specified in the CheckOrigin field to check
+// the origin. If the CheckOrigin function returns false, then the Upgrade
+// 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 deprecated Upgrade function does not enforce an origin policy. It's the
+// application's responsibility to check the Origin header before calling
+// Upgrade.
+//
+// Compression EXPERIMENTAL
+//
+// Per message compression extensions (RFC 7692) are experimentally supported
+// by this package in a limited capacity. Setting the EnableCompression option
+// to true in Dialer or Upgrader will attempt to negotiate per message deflate
+// support.
+//
+// var upgrader = websocket.Upgrader{
+// EnableCompression: true,
+// }
+//
+// If compression was successfully negotiated with the connection's peer, any
+// message received in compressed form will be automatically decompressed.
+// All Read methods will return uncompressed bytes.
+//
+// Per message compression of messages written to a connection can be enabled
+// or disabled by calling the corresponding Conn method:
+//
+// conn.EnableWriteCompression(false)
+//
+// Currently this package does not support compression with "context takeover".
+// This means that messages must be compressed and decompressed in isolation,
+// without retaining sliding window or dictionary state across messages. For
+// more details refer to RFC 7692.
+//
+// Use of compression is experimental and may result in decreased performance.
+package websocket
diff --git a/vendor/github.com/gorilla/websocket/json.go b/vendor/github.com/gorilla/websocket/json.go
new file mode 100644
index 000000000..4f0e36875
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/json.go
@@ -0,0 +1,55 @@
+// Copyright 2013 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 (
+ "encoding/json"
+ "io"
+)
+
+// WriteJSON is 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.
+//
+// See the documentation for encoding/json Marshal for details about the
+// conversion of Go values to JSON.
+func (c *Conn) WriteJSON(v interface{}) error {
+ w, err := c.NextWriter(TextMessage)
+ if err != nil {
+ return err
+ }
+ err1 := json.NewEncoder(w).Encode(v)
+ err2 := w.Close()
+ if err1 != nil {
+ return err1
+ }
+ return err2
+}
+
+// ReadJSON is deprecated, use c.ReadJSON instead.
+func ReadJSON(c *Conn, v interface{}) error {
+ return c.ReadJSON(v)
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// See the documentation for the encoding/json Unmarshal function for details
+// about the conversion of JSON to a Go value.
+func (c *Conn) ReadJSON(v interface{}) error {
+ _, r, err := c.NextReader()
+ if err != nil {
+ return err
+ }
+ err = json.NewDecoder(r).Decode(v)
+ if err == io.EOF {
+ // One value is expected in the message.
+ err = io.ErrUnexpectedEOF
+ }
+ return err
+}
diff --git a/vendor/github.com/gorilla/websocket/mask.go b/vendor/github.com/gorilla/websocket/mask.go
new file mode 100644
index 000000000..6a88bbc74
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/mask.go
@@ -0,0 +1,55 @@
+// 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 !appengine
+
+package websocket
+
+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 {
+ b[i] ^= key[pos&3]
+ pos++
+ }
+ return pos & 3
+ }
+
+ // Mask one byte at a time to word boundary.
+ if n := int(uintptr(unsafe.Pointer(&b[0]))) % wordSize; n != 0 {
+ n = wordSize - n
+ for i := range b[:n] {
+ b[i] ^= key[pos&3]
+ pos++
+ }
+ b = b[n:]
+ }
+
+ // Create aligned word size key.
+ var k [wordSize]byte
+ for i := range k {
+ k[i] = key[(pos+i)&3]
+ }
+ kw := *(*uintptr)(unsafe.Pointer(&k))
+
+ // Mask one word at a time.
+ n := (len(b) / wordSize) * wordSize
+ for i := 0; i < n; i += wordSize {
+ *(*uintptr)(unsafe.Pointer(uintptr(unsafe.Pointer(&b[0])) + uintptr(i))) ^= kw
+ }
+
+ // Mask one byte at a time for remaining bytes.
+ b = b[n:]
+ for i := range b {
+ b[i] ^= key[pos&3]
+ pos++
+ }
+
+ return pos & 3
+}
diff --git a/vendor/github.com/gorilla/websocket/prepared.go b/vendor/github.com/gorilla/websocket/prepared.go
new file mode 100644
index 000000000..1efffbd1e
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/prepared.go
@@ -0,0 +1,103 @@
+// 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 (
+ "bytes"
+ "net"
+ "sync"
+ "time"
+)
+
+// PreparedMessage caches on the wire representations of a message payload.
+// Use PreparedMessage to efficiently send a message payload to multiple
+// connections. PreparedMessage is especially useful when compression is used
+// because the CPU and memory expensive compression operation can be executed
+// once for a given set of compression options.
+type PreparedMessage struct {
+ messageType int
+ data []byte
+ err error
+ mu sync.Mutex
+ frames map[prepareKey]*preparedFrame
+}
+
+// prepareKey defines a unique set of options to cache prepared frames in PreparedMessage.
+type prepareKey struct {
+ isServer bool
+ compress bool
+ compressionLevel int
+}
+
+// preparedFrame contains data in wire representation.
+type preparedFrame struct {
+ once sync.Once
+ data []byte
+}
+
+// NewPreparedMessage returns an initialized PreparedMessage. You can then send
+// it to connection using WritePreparedMessage method. Valid wire
+// representation will be calculated lazily only once for a set of current
+// connection options.
+func NewPreparedMessage(messageType int, data []byte) (*PreparedMessage, error) {
+ pm := &PreparedMessage{
+ messageType: messageType,
+ frames: make(map[prepareKey]*preparedFrame),
+ data: data,
+ }
+
+ // Prepare a plain server frame.
+ _, frameData, err := pm.frame(prepareKey{isServer: true, compress: false})
+ if err != nil {
+ return nil, err
+ }
+
+ // To protect against caller modifying the data argument, remember the data
+ // copied to the plain server frame.
+ pm.data = frameData[len(frameData)-len(data):]
+ return pm, nil
+}
+
+func (pm *PreparedMessage) frame(key prepareKey) (int, []byte, error) {
+ pm.mu.Lock()
+ frame, ok := pm.frames[key]
+ if !ok {
+ frame = &preparedFrame{}
+ pm.frames[key] = frame
+ }
+ pm.mu.Unlock()
+
+ var err error
+ frame.once.Do(func() {
+ // Prepare a frame using a 'fake' connection.
+ // TODO: Refactor code in conn.go to allow more direct construction of
+ // the frame.
+ mu := make(chan bool, 1)
+ mu <- true
+ var nc prepareConn
+ c := &Conn{
+ conn: &nc,
+ mu: mu,
+ isServer: key.isServer,
+ compressionLevel: key.compressionLevel,
+ enableWriteCompression: true,
+ writeBuf: make([]byte, defaultWriteBufferSize+maxFrameHeaderSize),
+ }
+ if key.compress {
+ c.newCompressionWriter = compressNoContextTakeover
+ }
+ err = c.WriteMessage(pm.messageType, pm.data)
+ frame.data = nc.buf.Bytes()
+ })
+ return pm.messageType, frame.data, err
+}
+
+type prepareConn struct {
+ buf bytes.Buffer
+ net.Conn
+}
+
+func (pc *prepareConn) Write(p []byte) (int, error) { return pc.buf.Write(p) }
+func (pc *prepareConn) SetWriteDeadline(t time.Time) error { return nil }
diff --git a/vendor/github.com/gorilla/websocket/server.go b/vendor/github.com/gorilla/websocket/server.go
new file mode 100644
index 000000000..3495e0f1a
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/server.go
@@ -0,0 +1,291 @@
+// Copyright 2013 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"
+ "errors"
+ "net"
+ "net/http"
+ "net/url"
+ "strings"
+ "time"
+)
+
+// HandshakeError describes an error with the handshake from the peer.
+type HandshakeError struct {
+ message string
+}
+
+func (e HandshakeError) Error() string { return e.message }
+
+// Upgrader specifies parameters for upgrading an HTTP connection to a
+// WebSocket connection.
+type Upgrader struct {
+ // HandshakeTimeout specifies the duration for the handshake to complete.
+ HandshakeTimeout time.Duration
+
+ // ReadBufferSize and WriteBufferSize specify I/O buffer sizes. If a buffer
+ // size is zero, then buffers allocated by the HTTP server are used. The
+ // I/O buffer sizes do not limit the size of the messages that can be sent
+ // or received.
+ ReadBufferSize, WriteBufferSize int
+
+ // Subprotocols specifies the server's supported protocols in order of
+ // preference. If this field is set, then the Upgrade method negotiates a
+ // subprotocol by selecting the first match in this list with a protocol
+ // requested by the client.
+ Subprotocols []string
+
+ // Error specifies the function for generating HTTP error responses. If Error
+ // is nil, then http.Error is used to generate the HTTP response.
+ 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 func(r *http.Request) bool
+
+ // EnableCompression specify if the server 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
+}
+
+func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status int, reason string) (*Conn, error) {
+ err := HandshakeError{reason}
+ if u.Error != nil {
+ u.Error(w, r, status, err)
+ } else {
+ w.Header().Set("Sec-Websocket-Version", "13")
+ http.Error(w, http.StatusText(status), status)
+ }
+ return nil, err
+}
+
+// checkSameOrigin returns true if the origin is not set or is equal to the request host.
+func checkSameOrigin(r *http.Request) bool {
+ origin := r.Header["Origin"]
+ if len(origin) == 0 {
+ return true
+ }
+ u, err := url.Parse(origin[0])
+ if err != nil {
+ return false
+ }
+ return u.Host == r.Host
+}
+
+func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string {
+ if u.Subprotocols != nil {
+ clientProtocols := Subprotocols(r)
+ for _, serverProtocol := range u.Subprotocols {
+ for _, clientProtocol := range clientProtocols {
+ if clientProtocol == serverProtocol {
+ return clientProtocol
+ }
+ }
+ }
+ } else if responseHeader != nil {
+ return responseHeader.Get("Sec-Websocket-Protocol")
+ }
+ return ""
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// 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).
+//
+// 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")
+ }
+
+ 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")
+ }
+
+ 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")
+ }
+
+ 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")
+ }
+
+ checkOrigin := u.CheckOrigin
+ if checkOrigin == nil {
+ checkOrigin = checkSameOrigin
+ }
+ if !checkOrigin(r) {
+ return u.returnError(w, r, http.StatusForbidden, "websocket: 'Origin' header value not allowed")
+ }
+
+ 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")
+ }
+
+ subprotocol := u.selectSubprotocol(r, responseHeader)
+
+ // Negotiate PMCE
+ var compress bool
+ if u.EnableCompression {
+ for _, ext := range parseExtensions(r.Header) {
+ if ext[""] != "permessage-deflate" {
+ continue
+ }
+ compress = true
+ break
+ }
+ }
+
+ 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()
+ if err != nil {
+ return u.returnError(w, r, http.StatusInternalServerError, err.Error())
+ }
+
+ if brw.Reader.Buffered() > 0 {
+ netConn.Close()
+ return nil, errors.New("websocket: client sent data before handshake is complete")
+ }
+
+ c := newConnBRW(netConn, true, u.ReadBufferSize, u.WriteBufferSize, brw)
+ c.subprotocol = subprotocol
+
+ if compress {
+ c.newCompressionWriter = compressNoContextTakeover
+ c.newDecompressionReader = decompressNoContextTakeover
+ }
+
+ p := c.writeBuf[: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, 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"...)
+ }
+ for k, vs := range responseHeader {
+ if k == "Sec-Websocket-Protocol" {
+ continue
+ }
+ for _, v := range vs {
+ p = append(p, k...)
+ p = append(p, ": "...)
+ for i := 0; i < len(v); i++ {
+ b := v[i]
+ if b <= 31 {
+ // prevent response splitting.
+ b = ' '
+ }
+ p = append(p, b)
+ }
+ p = append(p, "\r\n"...)
+ }
+ }
+ p = append(p, "\r\n"...)
+
+ // Clear deadlines set by HTTP server.
+ netConn.SetDeadline(time.Time{})
+
+ if u.HandshakeTimeout > 0 {
+ netConn.SetWriteDeadline(time.Now().Add(u.HandshakeTimeout))
+ }
+ if _, err = netConn.Write(p); err != nil {
+ netConn.Close()
+ return nil, err
+ }
+ if u.HandshakeTimeout > 0 {
+ netConn.SetWriteDeadline(time.Time{})
+ }
+
+ return c, nil
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// This function is 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:
+//
+// if req.Header.Get("Origin") != "http://"+req.Host {
+// http.Error(w, "Origin not allowed", 403)
+// return
+// }
+//
+// If the endpoint supports subprotocols, then the application is responsible
+// for negotiating the protocol used on the connection. Use the Subprotocols()
+// function to get the subprotocols requested by the client. Use the
+// Sec-Websocket-Protocol response header to specify the subprotocol selected
+// by the application.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// negotiated subprotocol (Sec-Websocket-Protocol).
+//
+// The connection buffers IO to the underlying network connection. The
+// readBufSize and writeBufSize parameters specify the size of the buffers to
+// use. Messages can be larger than the buffers.
+//
+// If the request is not a valid WebSocket handshake, then Upgrade returns an
+// error of type HandshakeError. Applications should handle this error by
+// replying to the client with an HTTP error response.
+func Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header, readBufSize, writeBufSize int) (*Conn, error) {
+ u := Upgrader{ReadBufferSize: readBufSize, WriteBufferSize: writeBufSize}
+ u.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+ // don't return errors to maintain backwards compatibility
+ }
+ u.CheckOrigin = func(r *http.Request) bool {
+ // allow all connections by default
+ return true
+ }
+ return u.Upgrade(w, r, responseHeader)
+}
+
+// Subprotocols returns the subprotocols requested by the client in the
+// Sec-Websocket-Protocol header.
+func Subprotocols(r *http.Request) []string {
+ h := strings.TrimSpace(r.Header.Get("Sec-Websocket-Protocol"))
+ if h == "" {
+ return nil
+ }
+ protocols := strings.Split(h, ",")
+ for i := range protocols {
+ protocols[i] = strings.TrimSpace(protocols[i])
+ }
+ return protocols
+}
+
+// IsWebSocketUpgrade returns true if the client requested upgrade to the
+// WebSocket protocol.
+func IsWebSocketUpgrade(r *http.Request) bool {
+ return tokenListContainsValue(r.Header, "Connection", "upgrade") &&
+ tokenListContainsValue(r.Header, "Upgrade", "websocket")
+}
diff --git a/vendor/github.com/gorilla/websocket/util.go b/vendor/github.com/gorilla/websocket/util.go
new file mode 100644
index 000000000..9a4908df2
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/util.go
@@ -0,0 +1,214 @@
+// Copyright 2013 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 (
+ "crypto/rand"
+ "crypto/sha1"
+ "encoding/base64"
+ "io"
+ "net/http"
+ "strings"
+)
+
+var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
+
+func computeAcceptKey(challengeKey string) string {
+ h := sha1.New()
+ h.Write([]byte(challengeKey))
+ h.Write(keyGUID)
+ return base64.StdEncoding.EncodeToString(h.Sum(nil))
+}
+
+func generateChallengeKey() (string, error) {
+ p := make([]byte, 16)
+ if _, err := io.ReadFull(rand.Reader, p); err != nil {
+ return "", err
+ }
+ return base64.StdEncoding.EncodeToString(p), nil
+}
+
+// Octet types from RFC 2616.
+var octetTypes [256]byte
+
+const (
+ isTokenOctet = 1 << iota
+ isSpaceOctet
+)
+
+func init() {
+ // From RFC 2616
+ //
+ // OCTET = 
[](https://travis-ci.org/Sirupsen/logrus) [](https://godoc.org/github.com/Sirupsen/logrus)
+
+**Seeing weird case-sensitive problems?** See [this
+issue](https://github.com/sirupsen/logrus/issues/451#issuecomment-264332021).
+This change has been reverted. I apologize for causing this. I greatly
+underestimated the impact this would have. Logrus strives for stability and
+backwards compatibility and failed to provide that.
+
+Logrus is a structured logger for Go (golang), completely API compatible with
+the standard library logger. [Godoc][godoc]. **Please note the Logrus API is not
+yet stable (pre 1.0). Logrus itself is completely stable and has been used in
+many large deployments. The core API is unlikely to change much but please
+version control your Logrus to make sure you aren't fetching latest `master` on
+every build.**
+
+Nicely color-coded in development (when a TTY is attached, otherwise just
+plain text):
+
+
+
+With `log.SetFormatter(&log.JSONFormatter{})`, for easy parsing by logstash
+or Splunk:
+
+```json
+{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the
+ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"}
+
+{"level":"warning","msg":"The group's number increased tremendously!",
+"number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"A giant walrus appears!",
+"size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.",
+"size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"}
+
+{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true,
+"time":"2014-03-10 19:57:38.562543128 -0400 EDT"}
+```
+
+With the default `log.SetFormatter(&log.TextFormatter{})` when a TTY is not
+attached, the output is compatible with the
+[logfmt](http://godoc.org/github.com/kr/logfmt) format:
+
+```text
+time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8
+time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true
+time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4
+time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009
+time="2015-03-26T01:27:38-04:00" level=fatal msg="The ice breaks!" err=&{0x2082280c0 map[animal:orca size:9009] 2015-03-26 01:27:38.441574009 -0400 EDT panic It's over 9000!} number=100 omg=true
+exit status 1
+```
+
+#### Example
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+```go
+package main
+
+import (
+ log "github.com/Sirupsen/logrus"
+)
+
+func main() {
+ log.WithFields(log.Fields{
+ "animal": "walrus",
+ }).Info("A walrus appears")
+}
+```
+
+Note that it's completely api-compatible with the stdlib logger, so you can
+replace your `log` imports everywhere with `log "github.com/Sirupsen/logrus"`
+and you'll now have the flexibility of Logrus. You can customize it all you
+want:
+
+```go
+package main
+
+import (
+ "os"
+ log "github.com/Sirupsen/logrus"
+)
+
+func init() {
+ // Log as JSON instead of the default ASCII formatter.
+ log.SetFormatter(&log.JSONFormatter{})
+
+ // Output to stdout instead of the default stderr
+ // Can be any io.Writer, see below for File example
+ log.SetOutput(os.Stdout)
+
+ // Only log the warning severity or above.
+ log.SetLevel(log.WarnLevel)
+}
+
+func main() {
+ log.WithFields(log.Fields{
+ "animal": "walrus",
+ "size": 10,
+ }).Info("A group of walrus emerges from the ocean")
+
+ log.WithFields(log.Fields{
+ "omg": true,
+ "number": 122,
+ }).Warn("The group's number increased tremendously!")
+
+ log.WithFields(log.Fields{
+ "omg": true,
+ "number": 100,
+ }).Fatal("The ice breaks!")
+
+ // A common pattern is to re-use fields between logging statements by re-using
+ // the logrus.Entry returned from WithFields()
+ contextLogger := log.WithFields(log.Fields{
+ "common": "this is a common field",
+ "other": "I also should be logged always",
+ })
+
+ contextLogger.Info("I'll be logged with common and other field")
+ contextLogger.Info("Me too")
+}
+```
+
+For more advanced usage such as logging to multiple locations from the same
+application, you can also create an instance of the `logrus` Logger:
+
+```go
+package main
+
+import (
+ "os"
+ "github.com/Sirupsen/logrus"
+)
+
+// Create a new instance of the logger. You can have any number of instances.
+var log = logrus.New()
+
+func main() {
+ // The API for setting attributes is a little different than the package level
+ // exported logger. See Godoc.
+ log.Out = os.Stdout
+
+ // You could set this to any `io.Writer` such as a file
+ // file, err := os.OpenFile("logrus.log", os.O_CREATE|os.O_WRONLY, 0666)
+ // if err == nil {
+ // log.Out = file
+ // } else {
+ // log.Info("Failed to log to file, using default stderr")
+ // }
+
+ log.WithFields(logrus.Fields{
+ "animal": "walrus",
+ "size": 10,
+ }).Info("A group of walrus emerges from the ocean")
+}
+```
+
+#### Fields
+
+Logrus encourages careful, structured logging though logging fields instead of
+long, unparseable error messages. For example, instead of: `log.Fatalf("Failed
+to send event %s to topic %s with key %d")`, you should log the much more
+discoverable:
+
+```go
+log.WithFields(log.Fields{
+ "event": event,
+ "topic": topic,
+ "key": key,
+}).Fatal("Failed to send event")
+```
+
+We've found this API forces you to think about logging in a way that produces
+much more useful logging messages. We've been in countless situations where just
+a single added field to a log statement that was already there would've saved us
+hours. The `WithFields` call is optional.
+
+In general, with Logrus using any of the `printf`-family functions should be
+seen as a hint you should add a field, however, you can still use the
+`printf`-family functions with Logrus.
+
+#### Default Fields
+
+Often it's helpful to have fields _always_ attached to log statements in an
+application or parts of one. For example, you may want to always log the
+`request_id` and `user_ip` in the context of a request. Instead of writing
+`log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})` on
+every line, you can create a `logrus.Entry` to pass around instead:
+
+```go
+requestLogger := log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})
+requestLogger.Info("something happened on that request") # will log request_id and user_ip
+requestLogger.Warn("something not great happened")
+```
+
+#### Hooks
+
+You can add hooks for logging levels. For example to send errors to an exception
+tracking service on `Error`, `Fatal` and `Panic`, info to StatsD or log to
+multiple places simultaneously, e.g. syslog.
+
+Logrus comes with [built-in hooks](hooks/). Add those, or your custom hook, in
+`init`:
+
+```go
+import (
+ log "github.com/Sirupsen/logrus"
+ "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "aibrake"
+ logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog"
+ "log/syslog"
+)
+
+func init() {
+
+ // Use the Airbrake hook to report errors that have Error severity or above to
+ // an exception tracker. You can create custom hooks, see the Hooks section.
+ log.AddHook(airbrake.NewHook(123, "xyz", "production"))
+
+ hook, err := logrus_syslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+ if err != nil {
+ log.Error("Unable to connect to local syslog daemon")
+ } else {
+ log.AddHook(hook)
+ }
+}
+```
+Note: Syslog hook also support connecting to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). For the detail, please check the [syslog hook README](hooks/syslog/README.md).
+
+| Hook | Description |
+| ----- | ----------- |
+| [Airbrake "legacy"](https://github.com/gemnasium/logrus-airbrake-legacy-hook) | Send errors to an exception tracking service compatible with the Airbrake API V2. Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. |
+| [Airbrake](https://github.com/gemnasium/logrus-airbrake-hook) | Send errors to the Airbrake API V3. Uses the official [`gobrake`](https://github.com/airbrake/gobrake) behind the scenes. |
+| [Amazon Kinesis](https://github.com/evalphobia/logrus_kinesis) | Hook for logging to [Amazon Kinesis](https://aws.amazon.com/kinesis/) |
+| [Amqp-Hook](https://github.com/vladoatanasov/logrus_amqp) | Hook for logging to Amqp broker (Like RabbitMQ) |
+| [Bugsnag](https://github.com/Shopify/logrus-bugsnag/blob/master/bugsnag.go) | Send errors to the Bugsnag exception tracking service. |
+| [DeferPanic](https://github.com/deferpanic/dp-logrus) | Hook for logging to DeferPanic |
+| [Discordrus](https://github.com/kz/discordrus) | Hook for logging to [Discord](https://discordapp.com/) |
+| [ElasticSearch](https://github.com/sohlich/elogrus) | Hook for logging to ElasticSearch|
+| [Firehose](https://github.com/beaubrewer/firehose) | Hook for logging to [Amazon Firehose](https://aws.amazon.com/kinesis/firehose/)
+| [Fluentd](https://github.com/evalphobia/logrus_fluent) | Hook for logging to fluentd |
+| [Go-Slack](https://github.com/multiplay/go-slack) | Hook for logging to [Slack](https://slack.com) |
+| [Graylog](https://github.com/gemnasium/logrus-graylog-hook) | Hook for logging to [Graylog](http://graylog2.org/) |
+| [Hiprus](https://github.com/nubo/hiprus) | Send errors to a channel in hipchat. |
+| [Honeybadger](https://github.com/agonzalezro/logrus_honeybadger) | Hook for sending exceptions to Honeybadger |
+| [InfluxDB](https://github.com/Abramovic/logrus_influxdb) | Hook for logging to influxdb |
+| [Influxus] (http://github.com/vlad-doru/influxus) | Hook for concurrently logging to [InfluxDB] (http://influxdata.com/) |
+| [Journalhook](https://github.com/wercker/journalhook) | Hook for logging to `systemd-journald` |
+| [KafkaLogrus](https://github.com/goibibo/KafkaLogrus) | Hook for logging to kafka |
+| [LFShook](https://github.com/rifflock/lfshook) | Hook for logging to the local filesystem |
+| [Logentries](https://github.com/jcftang/logentriesrus) | Hook for logging to [Logentries](https://logentries.com/) |
+| [Logentrus](https://github.com/puddingfactory/logentrus) | Hook for logging to [Logentries](https://logentries.com/) |
+| [Logmatic.io](https://github.com/logmatic/logmatic-go) | Hook for logging to [Logmatic.io](http://logmatic.io/) |
+| [Logrusly](https://github.com/sebest/logrusly) | Send logs to [Loggly](https://www.loggly.com/) |
+| [Logstash](https://github.com/bshuster-repo/logrus-logstash-hook) | Hook for logging to [Logstash](https://www.elastic.co/products/logstash) |
+| [Mail](https://github.com/zbindenren/logrus_mail) | Hook for sending exceptions via mail |
+| [Mongodb](https://github.com/weekface/mgorus) | Hook for logging to mongodb |
+| [NATS-Hook](https://github.com/rybit/nats_logrus_hook) | Hook for logging to [NATS](https://nats.io) |
+| [Octokit](https://github.com/dorajistyle/logrus-octokit-hook) | Hook for logging to github via octokit |
+| [Papertrail](https://github.com/polds/logrus-papertrail-hook) | Send errors to the [Papertrail](https://papertrailapp.com) hosted logging service via UDP. |
+| [PostgreSQL](https://github.com/gemnasium/logrus-postgresql-hook) | Send logs to [PostgreSQL](http://postgresql.org) |
+| [Pushover](https://github.com/toorop/logrus_pushover) | Send error via [Pushover](https://pushover.net) |
+| [Raygun](https://github.com/squirkle/logrus-raygun-hook) | Hook for logging to [Raygun.io](http://raygun.io/) |
+| [Redis-Hook](https://github.com/rogierlommers/logrus-redis-hook) | Hook for logging to a ELK stack (through Redis) |
+| [Rollrus](https://github.com/heroku/rollrus) | Hook for sending errors to rollbar |
+| [Scribe](https://github.com/sagar8192/logrus-scribe-hook) | Hook for logging to [Scribe](https://github.com/facebookarchive/scribe)|
+| [Sentry](https://github.com/evalphobia/logrus_sentry) | Send errors to the Sentry error logging and aggregation service. |
+| [Slackrus](https://github.com/johntdyer/slackrus) | Hook for Slack chat. |
+| [Stackdriver](https://github.com/knq/sdhook) | Hook for logging to [Google Stackdriver](https://cloud.google.com/logging/) |
+| [Sumorus](https://github.com/doublefree/sumorus) | Hook for logging to [SumoLogic](https://www.sumologic.com/)|
+| [Syslog](https://github.com/Sirupsen/logrus/blob/master/hooks/syslog/syslog.go) | Send errors to remote syslog server. Uses standard library `log/syslog` behind the scenes. |
+| [TraceView](https://github.com/evalphobia/logrus_appneta) | Hook for logging to [AppNeta TraceView](https://www.appneta.com/products/traceview/) |
+| [Typetalk](https://github.com/dragon3/logrus-typetalk-hook) | Hook for logging to [Typetalk](https://www.typetalk.in/) |
+| [logz.io](https://github.com/ripcurld00d/logrus-logzio-hook) | Hook for logging to [logz.io](https://logz.io), a Log as a Service using Logstash |
+
+#### Level logging
+
+Logrus has six logging levels: Debug, Info, Warning, Error, Fatal and Panic.
+
+```go
+log.Debug("Useful debugging information.")
+log.Info("Something noteworthy happened!")
+log.Warn("You should probably take a look at this.")
+log.Error("Something failed but I'm not quitting.")
+// Calls os.Exit(1) after logging
+log.Fatal("Bye.")
+// Calls panic() after logging
+log.Panic("I'm bailing.")
+```
+
+You can set the logging level on a `Logger`, then it will only log entries with
+that severity or anything above it:
+
+```go
+// Will log anything that is info or above (warn, error, fatal, panic). Default.
+log.SetLevel(log.InfoLevel)
+```
+
+It may be useful to set `log.Level = logrus.DebugLevel` in a debug or verbose
+environment if your application has that.
+
+#### Entries
+
+Besides the fields added with `WithField` or `WithFields` some fields are
+automatically added to all logging events:
+
+1. `time`. The timestamp when the entry was created.
+2. `msg`. The logging message passed to `{Info,Warn,Error,Fatal,Panic}` after
+ the `AddFields` call. E.g. `Failed to send event.`
+3. `level`. The logging level. E.g. `info`.
+
+#### Environments
+
+Logrus has no notion of environment.
+
+If you wish for hooks and formatters to only be used in specific environments,
+you should handle that yourself. For example, if your application has a global
+variable `Environment`, which is a string representation of the environment you
+could do:
+
+```go
+import (
+ log "github.com/Sirupsen/logrus"
+)
+
+init() {
+ // do something here to set environment depending on an environment variable
+ // or command-line flag
+ if Environment == "production" {
+ log.SetFormatter(&log.JSONFormatter{})
+ } else {
+ // The TextFormatter is default, you don't actually have to do this.
+ log.SetFormatter(&log.TextFormatter{})
+ }
+}
+```
+
+This configuration is how `logrus` was intended to be used, but JSON in
+production is mostly only useful if you do log aggregation with tools like
+Splunk or Logstash.
+
+#### Formatters
+
+The built-in logging formatters are:
+
+* `logrus.TextFormatter`. Logs the event in colors if stdout is a tty, otherwise
+ without colors.
+ * *Note:* to force colored output when there is no TTY, set the `ForceColors`
+ field to `true`. To force no colored output even if there is a TTY set the
+ `DisableColors` field to `true`. For Windows, see
+ [github.com/mattn/go-colorable](https://github.com/mattn/go-colorable).
+ * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#TextFormatter).
+* `logrus.JSONFormatter`. Logs fields as JSON.
+ * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#JSONFormatter).
+
+Third party logging formatters:
+
+* [`logstash`](https://github.com/bshuster-repo/logrus-logstash-hook). Logs fields as [Logstash](http://logstash.net) Events.
+* [`prefixed`](https://github.com/x-cray/logrus-prefixed-formatter). Displays log entry source along with alternative layout.
+* [`zalgo`](https://github.com/aybabtme/logzalgo). Invoking the P͉̫o̳̼̊w̖͈̰͎e̬͔̭͂r͚̼̹̲ ̫͓͉̳͈ō̠͕͖̚f̝͍̠ ͕̲̞͖͑Z̖̫̤̫ͪa͉̬͈̗l͖͎g̳̥o̰̥̅!̣͔̲̻͊̄ ̙̘̦̹̦.
+
+You can define your formatter by implementing the `Formatter` interface,
+requiring a `Format` method. `Format` takes an `*Entry`. `entry.Data` is a
+`Fields` type (`map[string]interface{}`) with all your fields as well as the
+default ones (see Entries section above):
+
+```go
+type MyJSONFormatter struct {
+}
+
+log.SetFormatter(new(MyJSONFormatter))
+
+func (f *MyJSONFormatter) Format(entry *Entry) ([]byte, error) {
+ // Note this doesn't include Time, Level and Message which are available on
+ // the Entry. Consult `godoc` on information about those fields or read the
+ // source of the official loggers.
+ serialized, err := json.Marshal(entry.Data)
+ if err != nil {
+ return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+ }
+ return append(serialized, '\n'), nil
+}
+```
+
+#### Logger as an `io.Writer`
+
+Logrus can be transformed into an `io.Writer`. That writer is the end of an `io.Pipe` and it is your responsibility to close it.
+
+```go
+w := logger.Writer()
+defer w.Close()
+
+srv := http.Server{
+ // create a stdlib log.Logger that writes to
+ // logrus.Logger.
+ ErrorLog: log.New(w, "", 0),
+}
+```
+
+Each line written to that writer will be printed the usual way, using formatters
+and hooks. The level for those entries is `info`.
+
+This means that we can override the standard library logger easily:
+
+```go
+logger := logrus.New()
+logger.Formatter = &logrus.JSONFormatter{}
+
+// Use logrus for standard log output
+// Note that `log` here references stdlib's log
+// Not logrus imported under the name `log`.
+log.SetOutput(logger.Writer())
+```
+
+#### Rotation
+
+Log rotation is not provided with Logrus. Log rotation should be done by an
+external program (like `logrotate(8)`) that can compress and delete old log
+entries. It should not be a feature of the application-level logger.
+
+#### Tools
+
+| Tool | Description |
+| ---- | ----------- |
+|[Logrus Mate](https://github.com/gogap/logrus_mate)|Logrus mate is a tool for Logrus to manage loggers, you can initial logger's level, hook and formatter by config file, the logger will generated with different config at different environment.|
+|[Logrus Viper Helper](https://github.com/heirko/go-contrib/tree/master/logrusHelper)|An Helper around Logrus to wrap with spf13/Viper to load configuration with fangs! And to simplify Logrus configuration use some behavior of [Logrus Mate](https://github.com/gogap/logrus_mate). [sample](https://github.com/heirko/iris-contrib/blob/master/middleware/logrus-logger/example) |
+
+#### Testing
+
+Logrus has a built in facility for asserting the presence of log messages. This is implemented through the `test` hook and provides:
+
+* decorators for existing logger (`test.NewLocal` and `test.NewGlobal`) which basically just add the `test` hook
+* a test logger (`test.NewNullLogger`) that just records log messages (and does not output any):
+
+```go
+logger, hook := NewNullLogger()
+logger.Error("Hello error")
+
+assert.Equal(1, len(hook.Entries))
+assert.Equal(logrus.ErrorLevel, hook.LastEntry().Level)
+assert.Equal("Hello error", hook.LastEntry().Message)
+
+hook.Reset()
+assert.Nil(hook.LastEntry())
+```
+
+#### Fatal handlers
+
+Logrus can register one or more functions that will be called when any `fatal`
+level message is logged. The registered handlers will be executed before
+logrus performs a `os.Exit(1)`. This behavior may be helpful if callers need
+to gracefully shutdown. Unlike a `panic("Something went wrong...")` call which can be intercepted with a deferred `recover` a call to `os.Exit(1)` can not be intercepted.
+
+```
+...
+handler := func() {
+ // gracefully shutdown something...
+}
+logrus.RegisterExitHandler(handler)
+...
+```
+
+#### Thread safety
+
+By default Logger is protected by mutex for concurrent writes, this mutex is invoked when calling hooks and writing logs.
+If you are sure such locking is not needed, you can call logger.SetNoLock() to disable the locking.
+
+Situation when locking is not needed includes:
+
+* You have no hooks registered, or hooks calling is already thread-safe.
+
+* Writing to logger.Out is already thread-safe, for example:
+
+ 1) logger.Out is protected by locks.
+
+ 2) logger.Out is a os.File handler opened with `O_APPEND` flag, and every write is smaller than 4k. (This allow multi-thread/multi-process writing)
+
+ (Refer to http://www.notthewizard.com/2014/06/17/are-files-appends-really-atomic/)
diff --git a/vendor/github.com/Sirupsen/logrus/alt_exit.go b/vendor/github.com/Sirupsen/logrus/alt_exit.go
new file mode 100644
index 000000000..8af90637a
--- /dev/null
+++ b/vendor/github.com/Sirupsen/logrus/alt_exit.go
@@ -0,0 +1,64 @@
+package logrus
+
+// The following code was sourced and modified from the
+// https://github.com/tebeka/atexit package governed by the following license:
+//
+// Copyright (c) 2012 Miki Tebeka