Merge pull request #886 from fatedier/websocket

Connect protocol support websocket
This commit is contained in:
fatedier 2018-08-10 16:36:02 +08:00 committed by GitHub
commit f14ed87b29
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GPG Key ID: 4AEE18F83AFDEB23
12 changed files with 1480 additions and 57 deletions

7
Gopkg.lock generated
View File

@ -30,7 +30,7 @@
"net/mux",
"pool"
]
revision = "416571c55dbc32e13ce82c301a2a4b5a48ad7309"
revision = "280fa74053dee5311c46094f4bdefbf76d3fcbe2"
[[projects]]
branch = "frp"
@ -167,13 +167,14 @@
"internal/socket",
"internal/socks",
"ipv4",
"proxy"
"proxy",
"websocket"
]
revision = "dfa909b99c79129e1100513e5cd36307665e5723"
[solve-meta]
analyzer-name = "dep"
analyzer-version = 1
inputs-digest = "621310de53a9243693d20ce53690f373fd558440616fcf2893fec5ba4aa2b6ca"
inputs-digest = "58a51c884de4111bfa3d2f82a7cfe1cb91e9e8786fafdfdc8d306bed24f23e44"
solver-name = "gps-cdcl"
solver-version = 1

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@ -41,7 +41,7 @@ user = your_name
login_fail_exit = true
# communication protocol used to connect to server
# now it supports tcp and kcp, default is tcp
# now it supports tcp and kcp and websocket, default is tcp
protocol = tcp
# specify a dns server, so frpc will use this instead of default one

View File

@ -186,9 +186,10 @@ func UnmarshalClientConfFromIni(defaultCfg *ClientCommonConf, content string) (c
}
if tmpStr, ok = conf.Get("common", "protocol"); ok {
// Now it only support tcp and kcp.
if tmpStr != "kcp" {
tmpStr = "tcp"
// Now it only support tcp and kcp and websocket.
if tmpStr != "tcp" && tmpStr != "kcp" && tmpStr != "websocket" {
err = fmt.Errorf("Parse conf error: invalid protocol")
return
}
cfg.Protocol = tmpStr
}

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@ -15,6 +15,7 @@
package server
import (
"bytes"
"fmt"
"io/ioutil"
"net"
@ -53,6 +54,9 @@ type Service struct {
// Accept connections using kcp
kcpListener frpNet.Listener
// Accept connections using websocket
websocketListener frpNet.Listener
// For https proxies, route requests to different clients by hostname and other infomation
VhostHttpsMuxer *vhost.HttpsMuxer
@ -109,9 +113,6 @@ func NewService() (svr *Service, err error) {
if cfg.BindPort == cfg.VhostHttpsPort {
httpsMuxOn = true
}
if httpMuxOn || httpsMuxOn {
svr.muxer = mux.NewMux()
}
}
// Listen for accepting connections from client.
@ -120,10 +121,11 @@ func NewService() (svr *Service, err error) {
err = fmt.Errorf("Create server listener error, %v", err)
return
}
if svr.muxer != nil {
go svr.muxer.Serve(ln)
ln = svr.muxer.DefaultListener()
}
svr.muxer = mux.NewMux(ln)
go svr.muxer.Serve()
ln = svr.muxer.DefaultListener()
svr.listener = frpNet.WrapLogListener(ln)
log.Info("frps tcp listen on %s:%d", cfg.BindAddr, cfg.BindPort)
@ -137,6 +139,13 @@ func NewService() (svr *Service, err error) {
log.Info("frps kcp listen on udp %s:%d", cfg.BindAddr, cfg.KcpBindPort)
}
// Listen for accepting connections from client using websocket protocol.
websocketPrefix := []byte("GET " + frpNet.FrpWebsocketPath)
websocketLn := svr.muxer.Listen(0, uint32(len(websocketPrefix)), func(data []byte) bool {
return bytes.Equal(data, websocketPrefix)
})
svr.websocketListener = frpNet.NewWebsocketListener(websocketLn)
// Create http vhost muxer.
if cfg.VhostHttpPort > 0 {
rp := vhost.NewHttpReverseProxy(vhost.HttpReverseProxyOptions{
@ -151,7 +160,7 @@ func NewService() (svr *Service, err error) {
}
var l net.Listener
if httpMuxOn {
l = svr.muxer.ListenHttp(0)
l = svr.muxer.ListenHttp(1)
} else {
l, err = net.Listen("tcp", address)
if err != nil {
@ -167,7 +176,7 @@ func NewService() (svr *Service, err error) {
if cfg.VhostHttpsPort > 0 {
var l net.Listener
if httpsMuxOn {
l = svr.muxer.ListenHttps(0)
l = svr.muxer.ListenHttps(1)
} else {
l, err = net.Listen("tcp", fmt.Sprintf("%s:%d", cfg.ProxyBindAddr, cfg.VhostHttpsPort))
if err != nil {
@ -206,6 +215,7 @@ func NewService() (svr *Service, err error) {
}
log.Info("Dashboard listen on %s:%d", cfg.DashboardAddr, cfg.DashboardPort)
}
return
}
@ -216,8 +226,10 @@ func (svr *Service) Run() {
if g.GlbServerCfg.KcpBindPort > 0 {
go svr.HandleListener(svr.kcpListener)
}
svr.HandleListener(svr.listener)
go svr.HandleListener(svr.websocketListener)
svr.HandleListener(svr.listener)
}
func (svr *Service) HandleListener(l frpNet.Listener) {

View File

@ -96,45 +96,34 @@ func (conn *WrapReadWriteCloserConn) SetWriteDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "wrap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func ConnectServer(protocol string, addr string) (c Conn, err error) {
switch protocol {
case "tcp":
return ConnectTcpServer(addr)
case "kcp":
kcpConn, errRet := kcp.DialWithOptions(addr, nil, 10, 3)
if errRet != nil {
err = errRet
return
}
kcpConn.SetStreamMode(true)
kcpConn.SetWriteDelay(true)
kcpConn.SetNoDelay(1, 20, 2, 1)
kcpConn.SetWindowSize(128, 512)
kcpConn.SetMtu(1350)
kcpConn.SetACKNoDelay(false)
kcpConn.SetReadBuffer(4194304)
kcpConn.SetWriteBuffer(4194304)
c = WrapConn(kcpConn)
return
default:
return nil, fmt.Errorf("unsupport protocol: %s", protocol)
type CloseNotifyConn struct {
net.Conn
log.Logger
// 1 means closed
closeFlag int32
closeFn func()
}
// closeFn will be only called once
func WrapCloseNotifyConn(c net.Conn, closeFn func()) Conn {
return &CloseNotifyConn{
Conn: c,
Logger: log.NewPrefixLogger(""),
closeFn: closeFn,
}
}
func ConnectServerByProxy(proxyUrl string, protocol string, addr string) (c Conn, err error) {
switch protocol {
case "tcp":
var conn net.Conn
if conn, err = gnet.DialTcpByProxy(proxyUrl, addr); err != nil {
return
func (cc *CloseNotifyConn) Close() (err error) {
pflag := atomic.SwapInt32(&cc.closeFlag, 1)
if pflag == 0 {
err = cc.Close()
if cc.closeFn != nil {
cc.closeFn()
}
return WrapConn(conn), nil
case "kcp":
// http proxy is not supported for kcp
return ConnectServer(protocol, addr)
default:
return nil, fmt.Errorf("unsupport protocol: %s", protocol)
}
return
}
type StatsConn struct {
@ -175,3 +164,46 @@ func (statsConn *StatsConn) Close() (err error) {
}
return
}
func ConnectServer(protocol string, addr string) (c Conn, err error) {
switch protocol {
case "tcp":
return ConnectTcpServer(addr)
case "kcp":
kcpConn, errRet := kcp.DialWithOptions(addr, nil, 10, 3)
if errRet != nil {
err = errRet
return
}
kcpConn.SetStreamMode(true)
kcpConn.SetWriteDelay(true)
kcpConn.SetNoDelay(1, 20, 2, 1)
kcpConn.SetWindowSize(128, 512)
kcpConn.SetMtu(1350)
kcpConn.SetACKNoDelay(false)
kcpConn.SetReadBuffer(4194304)
kcpConn.SetWriteBuffer(4194304)
c = WrapConn(kcpConn)
return
default:
return nil, fmt.Errorf("unsupport protocol: %s", protocol)
}
}
func ConnectServerByProxy(proxyUrl string, protocol string, addr string) (c Conn, err error) {
switch protocol {
case "tcp":
var conn net.Conn
if conn, err = gnet.DialTcpByProxy(proxyUrl, addr); err != nil {
return
}
return WrapConn(conn), nil
case "kcp":
// http proxy is not supported for kcp
return ConnectServer(protocol, addr)
case "websocket":
return ConnectWebsocketServer(addr)
default:
return nil, fmt.Errorf("unsupport protocol: %s", protocol)
}
}

105
utils/net/websocket.go Normal file
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@ -0,0 +1,105 @@
package net
import (
"errors"
"fmt"
"net"
"net/http"
"net/url"
"time"
"github.com/fatedier/frp/utils/log"
"golang.org/x/net/websocket"
)
var (
ErrWebsocketListenerClosed = errors.New("websocket listener closed")
)
const (
FrpWebsocketPath = "/~!frp"
)
type WebsocketListener struct {
net.Addr
ln net.Listener
accept chan Conn
log.Logger
server *http.Server
httpMutex *http.ServeMux
}
// ln: tcp listener for websocket connections
func NewWebsocketListener(ln net.Listener) (wl *WebsocketListener) {
wl = &WebsocketListener{
Addr: ln.Addr(),
accept: make(chan Conn),
Logger: log.NewPrefixLogger(""),
}
muxer := http.NewServeMux()
muxer.Handle(FrpWebsocketPath, websocket.Handler(func(c *websocket.Conn) {
notifyCh := make(chan struct{})
conn := WrapCloseNotifyConn(c, func() {
close(notifyCh)
})
wl.accept <- conn
<-notifyCh
}))
wl.server = &http.Server{
Addr: ln.Addr().String(),
Handler: muxer,
}
go wl.server.Serve(ln)
return
}
func ListenWebsocket(bindAddr string, bindPort int) (*WebsocketListener, error) {
tcpLn, err := net.Listen("tcp", fmt.Sprintf("%s:%d", bindAddr, bindPort))
if err != nil {
return nil, err
}
l := NewWebsocketListener(tcpLn)
return l, nil
}
func (p *WebsocketListener) Accept() (Conn, error) {
c, ok := <-p.accept
if !ok {
return nil, ErrWebsocketListenerClosed
}
return c, nil
}
func (p *WebsocketListener) Close() error {
return p.server.Close()
}
// addr: domain:port
func ConnectWebsocketServer(addr string) (Conn, error) {
addr = "ws://" + addr + FrpWebsocketPath
uri, err := url.Parse(addr)
if err != nil {
return nil, err
}
origin := "http://" + uri.Host
cfg, err := websocket.NewConfig(addr, origin)
if err != nil {
return nil, err
}
cfg.Dialer = &net.Dialer{
Timeout: 10 * time.Second,
}
conn, err := websocket.DialConfig(cfg)
if err != nil {
return nil, err
}
c := WrapConn(conn)
return c, nil
}

View File

@ -43,8 +43,9 @@ type Mux struct {
mu sync.RWMutex
}
func NewMux() (mux *Mux) {
func NewMux(ln net.Listener) (mux *Mux) {
mux = &Mux{
ln: ln,
lns: make([]*listener, 0),
}
return
@ -123,15 +124,12 @@ func (mux *Mux) copyLns() []*listener {
}
// Serve handles connections from ln and multiplexes then across registered listeners.
func (mux *Mux) Serve(ln net.Listener) error {
mux.mu.Lock()
mux.ln = ln
mux.mu.Unlock()
func (mux *Mux) Serve() error {
for {
// Wait for the next connection.
// If it returns a temporary error then simply retry.
// If it returns any other error then exit immediately.
conn, err := ln.Accept()
conn, err := mux.ln.Accept()
if err, ok := err.(interface {
Temporary() bool
}); ok && err.Temporary() {

106
vendor/golang.org/x/net/websocket/client.go generated vendored Normal file
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@ -0,0 +1,106 @@
// Copyright 2009 The Go 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"
"io"
"net"
"net/http"
"net/url"
)
// DialError is an error that occurs while dialling a websocket server.
type DialError struct {
*Config
Err error
}
func (e *DialError) Error() string {
return "websocket.Dial " + e.Config.Location.String() + ": " + e.Err.Error()
}
// NewConfig creates a new WebSocket config for client connection.
func NewConfig(server, origin string) (config *Config, err error) {
config = new(Config)
config.Version = ProtocolVersionHybi13
config.Location, err = url.ParseRequestURI(server)
if err != nil {
return
}
config.Origin, err = url.ParseRequestURI(origin)
if err != nil {
return
}
config.Header = http.Header(make(map[string][]string))
return
}
// NewClient creates a new WebSocket client connection over rwc.
func NewClient(config *Config, rwc io.ReadWriteCloser) (ws *Conn, err error) {
br := bufio.NewReader(rwc)
bw := bufio.NewWriter(rwc)
err = hybiClientHandshake(config, br, bw)
if err != nil {
return
}
buf := bufio.NewReadWriter(br, bw)
ws = newHybiClientConn(config, buf, rwc)
return
}
// Dial opens a new client connection to a WebSocket.
func Dial(url_, protocol, origin string) (ws *Conn, err error) {
config, err := NewConfig(url_, origin)
if err != nil {
return nil, err
}
if protocol != "" {
config.Protocol = []string{protocol}
}
return DialConfig(config)
}
var portMap = map[string]string{
"ws": "80",
"wss": "443",
}
func parseAuthority(location *url.URL) string {
if _, ok := portMap[location.Scheme]; ok {
if _, _, err := net.SplitHostPort(location.Host); err != nil {
return net.JoinHostPort(location.Host, portMap[location.Scheme])
}
}
return location.Host
}
// DialConfig opens a new client connection to a WebSocket with a config.
func DialConfig(config *Config) (ws *Conn, err error) {
var client net.Conn
if config.Location == nil {
return nil, &DialError{config, ErrBadWebSocketLocation}
}
if config.Origin == nil {
return nil, &DialError{config, ErrBadWebSocketOrigin}
}
dialer := config.Dialer
if dialer == nil {
dialer = &net.Dialer{}
}
client, err = dialWithDialer(dialer, config)
if err != nil {
goto Error
}
ws, err = NewClient(config, client)
if err != nil {
client.Close()
goto Error
}
return
Error:
return nil, &DialError{config, err}
}

24
vendor/golang.org/x/net/websocket/dial.go generated vendored Normal file
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@ -0,0 +1,24 @@
// Copyright 2015 The Go 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/tls"
"net"
)
func dialWithDialer(dialer *net.Dialer, config *Config) (conn net.Conn, err error) {
switch config.Location.Scheme {
case "ws":
conn, err = dialer.Dial("tcp", parseAuthority(config.Location))
case "wss":
conn, err = tls.DialWithDialer(dialer, "tcp", parseAuthority(config.Location), config.TlsConfig)
default:
err = ErrBadScheme
}
return
}

583
vendor/golang.org/x/net/websocket/hybi.go generated vendored Normal file
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@ -0,0 +1,583 @@
// Copyright 2011 The Go 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
// This file implements a protocol of hybi draft.
// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17
import (
"bufio"
"bytes"
"crypto/rand"
"crypto/sha1"
"encoding/base64"
"encoding/binary"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"strings"
)
const (
websocketGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
closeStatusNormal = 1000
closeStatusGoingAway = 1001
closeStatusProtocolError = 1002
closeStatusUnsupportedData = 1003
closeStatusFrameTooLarge = 1004
closeStatusNoStatusRcvd = 1005
closeStatusAbnormalClosure = 1006
closeStatusBadMessageData = 1007
closeStatusPolicyViolation = 1008
closeStatusTooBigData = 1009
closeStatusExtensionMismatch = 1010
maxControlFramePayloadLength = 125
)
var (
ErrBadMaskingKey = &ProtocolError{"bad masking key"}
ErrBadPongMessage = &ProtocolError{"bad pong message"}
ErrBadClosingStatus = &ProtocolError{"bad closing status"}
ErrUnsupportedExtensions = &ProtocolError{"unsupported extensions"}
ErrNotImplemented = &ProtocolError{"not implemented"}
handshakeHeader = map[string]bool{
"Host": true,
"Upgrade": true,
"Connection": true,
"Sec-Websocket-Key": true,
"Sec-Websocket-Origin": true,
"Sec-Websocket-Version": true,
"Sec-Websocket-Protocol": true,
"Sec-Websocket-Accept": true,
}
)
// A hybiFrameHeader is a frame header as defined in hybi draft.
type hybiFrameHeader struct {
Fin bool
Rsv [3]bool
OpCode byte
Length int64
MaskingKey []byte
data *bytes.Buffer
}
// A hybiFrameReader is a reader for hybi frame.
type hybiFrameReader struct {
reader io.Reader
header hybiFrameHeader
pos int64
length int
}
func (frame *hybiFrameReader) Read(msg []byte) (n int, err error) {
n, err = frame.reader.Read(msg)
if frame.header.MaskingKey != nil {
for i := 0; i < n; i++ {
msg[i] = msg[i] ^ frame.header.MaskingKey[frame.pos%4]
frame.pos++
}
}
return n, err
}
func (frame *hybiFrameReader) PayloadType() byte { return frame.header.OpCode }
func (frame *hybiFrameReader) HeaderReader() io.Reader {
if frame.header.data == nil {
return nil
}
if frame.header.data.Len() == 0 {
return nil
}
return frame.header.data
}
func (frame *hybiFrameReader) TrailerReader() io.Reader { return nil }
func (frame *hybiFrameReader) Len() (n int) { return frame.length }
// A hybiFrameReaderFactory creates new frame reader based on its frame type.
type hybiFrameReaderFactory struct {
*bufio.Reader
}
// NewFrameReader reads a frame header from the connection, and creates new reader for the frame.
// See Section 5.2 Base Framing protocol for detail.
// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17#section-5.2
func (buf hybiFrameReaderFactory) NewFrameReader() (frame frameReader, err error) {
hybiFrame := new(hybiFrameReader)
frame = hybiFrame
var header []byte
var b byte
// First byte. FIN/RSV1/RSV2/RSV3/OpCode(4bits)
b, err = buf.ReadByte()
if err != nil {
return
}
header = append(header, b)
hybiFrame.header.Fin = ((header[0] >> 7) & 1) != 0
for i := 0; i < 3; i++ {
j := uint(6 - i)
hybiFrame.header.Rsv[i] = ((header[0] >> j) & 1) != 0
}
hybiFrame.header.OpCode = header[0] & 0x0f
// Second byte. Mask/Payload len(7bits)
b, err = buf.ReadByte()
if err != nil {
return
}
header = append(header, b)
mask := (b & 0x80) != 0
b &= 0x7f
lengthFields := 0
switch {
case b <= 125: // Payload length 7bits.
hybiFrame.header.Length = int64(b)
case b == 126: // Payload length 7+16bits
lengthFields = 2
case b == 127: // Payload length 7+64bits
lengthFields = 8
}
for i := 0; i < lengthFields; i++ {
b, err = buf.ReadByte()
if err != nil {
return
}
if lengthFields == 8 && i == 0 { // MSB must be zero when 7+64 bits
b &= 0x7f
}
header = append(header, b)
hybiFrame.header.Length = hybiFrame.header.Length*256 + int64(b)
}
if mask {
// Masking key. 4 bytes.
for i := 0; i < 4; i++ {
b, err = buf.ReadByte()
if err != nil {
return
}
header = append(header, b)
hybiFrame.header.MaskingKey = append(hybiFrame.header.MaskingKey, b)
}
}
hybiFrame.reader = io.LimitReader(buf.Reader, hybiFrame.header.Length)
hybiFrame.header.data = bytes.NewBuffer(header)
hybiFrame.length = len(header) + int(hybiFrame.header.Length)
return
}
// A HybiFrameWriter is a writer for hybi frame.
type hybiFrameWriter struct {
writer *bufio.Writer
header *hybiFrameHeader
}
func (frame *hybiFrameWriter) Write(msg []byte) (n int, err error) {
var header []byte
var b byte
if frame.header.Fin {
b |= 0x80
}
for i := 0; i < 3; i++ {
if frame.header.Rsv[i] {
j := uint(6 - i)
b |= 1 << j
}
}
b |= frame.header.OpCode
header = append(header, b)
if frame.header.MaskingKey != nil {
b = 0x80
} else {
b = 0
}
lengthFields := 0
length := len(msg)
switch {
case length <= 125:
b |= byte(length)
case length < 65536:
b |= 126
lengthFields = 2
default:
b |= 127
lengthFields = 8
}
header = append(header, b)
for i := 0; i < lengthFields; i++ {
j := uint((lengthFields - i - 1) * 8)
b = byte((length >> j) & 0xff)
header = append(header, b)
}
if frame.header.MaskingKey != nil {
if len(frame.header.MaskingKey) != 4 {
return 0, ErrBadMaskingKey
}
header = append(header, frame.header.MaskingKey...)
frame.writer.Write(header)
data := make([]byte, length)
for i := range data {
data[i] = msg[i] ^ frame.header.MaskingKey[i%4]
}
frame.writer.Write(data)
err = frame.writer.Flush()
return length, err
}
frame.writer.Write(header)
frame.writer.Write(msg)
err = frame.writer.Flush()
return length, err
}
func (frame *hybiFrameWriter) Close() error { return nil }
type hybiFrameWriterFactory struct {
*bufio.Writer
needMaskingKey bool
}
func (buf hybiFrameWriterFactory) NewFrameWriter(payloadType byte) (frame frameWriter, err error) {
frameHeader := &hybiFrameHeader{Fin: true, OpCode: payloadType}
if buf.needMaskingKey {
frameHeader.MaskingKey, err = generateMaskingKey()
if err != nil {
return nil, err
}
}
return &hybiFrameWriter{writer: buf.Writer, header: frameHeader}, nil
}
type hybiFrameHandler struct {
conn *Conn
payloadType byte
}
func (handler *hybiFrameHandler) HandleFrame(frame frameReader) (frameReader, error) {
if handler.conn.IsServerConn() {
// The client MUST mask all frames sent to the server.
if frame.(*hybiFrameReader).header.MaskingKey == nil {
handler.WriteClose(closeStatusProtocolError)
return nil, io.EOF
}
} else {
// The server MUST NOT mask all frames.
if frame.(*hybiFrameReader).header.MaskingKey != nil {
handler.WriteClose(closeStatusProtocolError)
return nil, io.EOF
}
}
if header := frame.HeaderReader(); header != nil {
io.Copy(ioutil.Discard, header)
}
switch frame.PayloadType() {
case ContinuationFrame:
frame.(*hybiFrameReader).header.OpCode = handler.payloadType
case TextFrame, BinaryFrame:
handler.payloadType = frame.PayloadType()
case CloseFrame:
return nil, io.EOF
case PingFrame, PongFrame:
b := make([]byte, maxControlFramePayloadLength)
n, err := io.ReadFull(frame, b)
if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
return nil, err
}
io.Copy(ioutil.Discard, frame)
if frame.PayloadType() == PingFrame {
if _, err := handler.WritePong(b[:n]); err != nil {
return nil, err
}
}
return nil, nil
}
return frame, nil
}
func (handler *hybiFrameHandler) WriteClose(status int) (err error) {
handler.conn.wio.Lock()
defer handler.conn.wio.Unlock()
w, err := handler.conn.frameWriterFactory.NewFrameWriter(CloseFrame)
if err != nil {
return err
}
msg := make([]byte, 2)
binary.BigEndian.PutUint16(msg, uint16(status))
_, err = w.Write(msg)
w.Close()
return err
}
func (handler *hybiFrameHandler) WritePong(msg []byte) (n int, err error) {
handler.conn.wio.Lock()
defer handler.conn.wio.Unlock()
w, err := handler.conn.frameWriterFactory.NewFrameWriter(PongFrame)
if err != nil {
return 0, err
}
n, err = w.Write(msg)
w.Close()
return n, err
}
// newHybiConn creates a new WebSocket connection speaking hybi draft protocol.
func newHybiConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
if buf == nil {
br := bufio.NewReader(rwc)
bw := bufio.NewWriter(rwc)
buf = bufio.NewReadWriter(br, bw)
}
ws := &Conn{config: config, request: request, buf: buf, rwc: rwc,
frameReaderFactory: hybiFrameReaderFactory{buf.Reader},
frameWriterFactory: hybiFrameWriterFactory{
buf.Writer, request == nil},
PayloadType: TextFrame,
defaultCloseStatus: closeStatusNormal}
ws.frameHandler = &hybiFrameHandler{conn: ws}
return ws
}
// generateMaskingKey generates a masking key for a frame.
func generateMaskingKey() (maskingKey []byte, err error) {
maskingKey = make([]byte, 4)
if _, err = io.ReadFull(rand.Reader, maskingKey); err != nil {
return
}
return
}
// generateNonce generates a nonce consisting of a randomly selected 16-byte
// value that has been base64-encoded.
func generateNonce() (nonce []byte) {
key := make([]byte, 16)
if _, err := io.ReadFull(rand.Reader, key); err != nil {
panic(err)
}
nonce = make([]byte, 24)
base64.StdEncoding.Encode(nonce, key)
return
}
// removeZone removes IPv6 zone identifer from host.
// E.g., "[fe80::1%en0]:8080" to "[fe80::1]:8080"
func removeZone(host string) string {
if !strings.HasPrefix(host, "[") {
return host
}
i := strings.LastIndex(host, "]")
if i < 0 {
return host
}
j := strings.LastIndex(host[:i], "%")
if j < 0 {
return host
}
return host[:j] + host[i:]
}
// getNonceAccept computes the base64-encoded SHA-1 of the concatenation of
// the nonce ("Sec-WebSocket-Key" value) with the websocket GUID string.
func getNonceAccept(nonce []byte) (expected []byte, err error) {
h := sha1.New()
if _, err = h.Write(nonce); err != nil {
return
}
if _, err = h.Write([]byte(websocketGUID)); err != nil {
return
}
expected = make([]byte, 28)
base64.StdEncoding.Encode(expected, h.Sum(nil))
return
}
// Client handshake described in draft-ietf-hybi-thewebsocket-protocol-17
func hybiClientHandshake(config *Config, br *bufio.Reader, bw *bufio.Writer) (err error) {
bw.WriteString("GET " + config.Location.RequestURI() + " HTTP/1.1\r\n")
// According to RFC 6874, an HTTP client, proxy, or other
// intermediary must remove any IPv6 zone identifier attached
// to an outgoing URI.
bw.WriteString("Host: " + removeZone(config.Location.Host) + "\r\n")
bw.WriteString("Upgrade: websocket\r\n")
bw.WriteString("Connection: Upgrade\r\n")
nonce := generateNonce()
if config.handshakeData != nil {
nonce = []byte(config.handshakeData["key"])
}
bw.WriteString("Sec-WebSocket-Key: " + string(nonce) + "\r\n")
bw.WriteString("Origin: " + strings.ToLower(config.Origin.String()) + "\r\n")
if config.Version != ProtocolVersionHybi13 {
return ErrBadProtocolVersion
}
bw.WriteString("Sec-WebSocket-Version: " + fmt.Sprintf("%d", config.Version) + "\r\n")
if len(config.Protocol) > 0 {
bw.WriteString("Sec-WebSocket-Protocol: " + strings.Join(config.Protocol, ", ") + "\r\n")
}
// TODO(ukai): send Sec-WebSocket-Extensions.
err = config.Header.WriteSubset(bw, handshakeHeader)
if err != nil {
return err
}
bw.WriteString("\r\n")
if err = bw.Flush(); err != nil {
return err
}
resp, err := http.ReadResponse(br, &http.Request{Method: "GET"})
if err != nil {
return err
}
if resp.StatusCode != 101 {
return ErrBadStatus
}
if strings.ToLower(resp.Header.Get("Upgrade")) != "websocket" ||
strings.ToLower(resp.Header.Get("Connection")) != "upgrade" {
return ErrBadUpgrade
}
expectedAccept, err := getNonceAccept(nonce)
if err != nil {
return err
}
if resp.Header.Get("Sec-WebSocket-Accept") != string(expectedAccept) {
return ErrChallengeResponse
}
if resp.Header.Get("Sec-WebSocket-Extensions") != "" {
return ErrUnsupportedExtensions
}
offeredProtocol := resp.Header.Get("Sec-WebSocket-Protocol")
if offeredProtocol != "" {
protocolMatched := false
for i := 0; i < len(config.Protocol); i++ {
if config.Protocol[i] == offeredProtocol {
protocolMatched = true
break
}
}
if !protocolMatched {
return ErrBadWebSocketProtocol
}
config.Protocol = []string{offeredProtocol}
}
return nil
}
// newHybiClientConn creates a client WebSocket connection after handshake.
func newHybiClientConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser) *Conn {
return newHybiConn(config, buf, rwc, nil)
}
// A HybiServerHandshaker performs a server handshake using hybi draft protocol.
type hybiServerHandshaker struct {
*Config
accept []byte
}
func (c *hybiServerHandshaker) ReadHandshake(buf *bufio.Reader, req *http.Request) (code int, err error) {
c.Version = ProtocolVersionHybi13
if req.Method != "GET" {
return http.StatusMethodNotAllowed, ErrBadRequestMethod
}
// HTTP version can be safely ignored.
if strings.ToLower(req.Header.Get("Upgrade")) != "websocket" ||
!strings.Contains(strings.ToLower(req.Header.Get("Connection")), "upgrade") {
return http.StatusBadRequest, ErrNotWebSocket
}
key := req.Header.Get("Sec-Websocket-Key")
if key == "" {
return http.StatusBadRequest, ErrChallengeResponse
}
version := req.Header.Get("Sec-Websocket-Version")
switch version {
case "13":
c.Version = ProtocolVersionHybi13
default:
return http.StatusBadRequest, ErrBadWebSocketVersion
}
var scheme string
if req.TLS != nil {
scheme = "wss"
} else {
scheme = "ws"
}
c.Location, err = url.ParseRequestURI(scheme + "://" + req.Host + req.URL.RequestURI())
if err != nil {
return http.StatusBadRequest, err
}
protocol := strings.TrimSpace(req.Header.Get("Sec-Websocket-Protocol"))
if protocol != "" {
protocols := strings.Split(protocol, ",")
for i := 0; i < len(protocols); i++ {
c.Protocol = append(c.Protocol, strings.TrimSpace(protocols[i]))
}
}
c.accept, err = getNonceAccept([]byte(key))
if err != nil {
return http.StatusInternalServerError, err
}
return http.StatusSwitchingProtocols, nil
}
// Origin parses the Origin header in req.
// If the Origin header is not set, it returns nil and nil.
func Origin(config *Config, req *http.Request) (*url.URL, error) {
var origin string
switch config.Version {
case ProtocolVersionHybi13:
origin = req.Header.Get("Origin")
}
if origin == "" {
return nil, nil
}
return url.ParseRequestURI(origin)
}
func (c *hybiServerHandshaker) AcceptHandshake(buf *bufio.Writer) (err error) {
if len(c.Protocol) > 0 {
if len(c.Protocol) != 1 {
// You need choose a Protocol in Handshake func in Server.
return ErrBadWebSocketProtocol
}
}
buf.WriteString("HTTP/1.1 101 Switching Protocols\r\n")
buf.WriteString("Upgrade: websocket\r\n")
buf.WriteString("Connection: Upgrade\r\n")
buf.WriteString("Sec-WebSocket-Accept: " + string(c.accept) + "\r\n")
if len(c.Protocol) > 0 {
buf.WriteString("Sec-WebSocket-Protocol: " + c.Protocol[0] + "\r\n")
}
// TODO(ukai): send Sec-WebSocket-Extensions.
if c.Header != nil {
err := c.Header.WriteSubset(buf, handshakeHeader)
if err != nil {
return err
}
}
buf.WriteString("\r\n")
return buf.Flush()
}
func (c *hybiServerHandshaker) NewServerConn(buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
return newHybiServerConn(c.Config, buf, rwc, request)
}
// newHybiServerConn returns a new WebSocket connection speaking hybi draft protocol.
func newHybiServerConn(config *Config, buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) *Conn {
return newHybiConn(config, buf, rwc, request)
}

113
vendor/golang.org/x/net/websocket/server.go generated vendored Normal file
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// Copyright 2009 The Go 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"
"fmt"
"io"
"net/http"
)
func newServerConn(rwc io.ReadWriteCloser, buf *bufio.ReadWriter, req *http.Request, config *Config, handshake func(*Config, *http.Request) error) (conn *Conn, err error) {
var hs serverHandshaker = &hybiServerHandshaker{Config: config}
code, err := hs.ReadHandshake(buf.Reader, req)
if err == ErrBadWebSocketVersion {
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
fmt.Fprintf(buf, "Sec-WebSocket-Version: %s\r\n", SupportedProtocolVersion)
buf.WriteString("\r\n")
buf.WriteString(err.Error())
buf.Flush()
return
}
if err != nil {
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
buf.WriteString("\r\n")
buf.WriteString(err.Error())
buf.Flush()
return
}
if handshake != nil {
err = handshake(config, req)
if err != nil {
code = http.StatusForbidden
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
buf.WriteString("\r\n")
buf.Flush()
return
}
}
err = hs.AcceptHandshake(buf.Writer)
if err != nil {
code = http.StatusBadRequest
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
buf.WriteString("\r\n")
buf.Flush()
return
}
conn = hs.NewServerConn(buf, rwc, req)
return
}
// Server represents a server of a WebSocket.
type Server struct {
// Config is a WebSocket configuration for new WebSocket connection.
Config
// Handshake is an optional function in WebSocket handshake.
// For example, you can check, or don't check Origin header.
// Another example, you can select config.Protocol.
Handshake func(*Config, *http.Request) error
// Handler handles a WebSocket connection.
Handler
}
// ServeHTTP implements the http.Handler interface for a WebSocket
func (s Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
s.serveWebSocket(w, req)
}
func (s Server) serveWebSocket(w http.ResponseWriter, req *http.Request) {
rwc, buf, err := w.(http.Hijacker).Hijack()
if err != nil {
panic("Hijack failed: " + err.Error())
}
// The server should abort the WebSocket connection if it finds
// the client did not send a handshake that matches with protocol
// specification.
defer rwc.Close()
conn, err := newServerConn(rwc, buf, req, &s.Config, s.Handshake)
if err != nil {
return
}
if conn == nil {
panic("unexpected nil conn")
}
s.Handler(conn)
}
// Handler is a simple interface to a WebSocket browser client.
// It checks if Origin header is valid URL by default.
// You might want to verify websocket.Conn.Config().Origin in the func.
// If you use Server instead of Handler, you could call websocket.Origin and
// check the origin in your Handshake func. So, if you want to accept
// non-browser clients, which do not send an Origin header, set a
// Server.Handshake that does not check the origin.
type Handler func(*Conn)
func checkOrigin(config *Config, req *http.Request) (err error) {
config.Origin, err = Origin(config, req)
if err == nil && config.Origin == nil {
return fmt.Errorf("null origin")
}
return err
}
// ServeHTTP implements the http.Handler interface for a WebSocket
func (h Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
s := Server{Handler: h, Handshake: checkOrigin}
s.serveWebSocket(w, req)
}

448
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// Copyright 2009 The Go 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 a client and server for the WebSocket protocol
// as specified in RFC 6455.
//
// This package currently lacks some features found in an alternative
// and more actively maintained WebSocket package:
//
// https://godoc.org/github.com/gorilla/websocket
//
package websocket // import "golang.org/x/net/websocket"
import (
"bufio"
"crypto/tls"
"encoding/json"
"errors"
"io"
"io/ioutil"
"net"
"net/http"
"net/url"
"sync"
"time"
)
const (
ProtocolVersionHybi13 = 13
ProtocolVersionHybi = ProtocolVersionHybi13
SupportedProtocolVersion = "13"
ContinuationFrame = 0
TextFrame = 1
BinaryFrame = 2
CloseFrame = 8
PingFrame = 9
PongFrame = 10
UnknownFrame = 255
DefaultMaxPayloadBytes = 32 << 20 // 32MB
)
// ProtocolError represents WebSocket protocol errors.
type ProtocolError struct {
ErrorString string
}
func (err *ProtocolError) Error() string { return err.ErrorString }
var (
ErrBadProtocolVersion = &ProtocolError{"bad protocol version"}
ErrBadScheme = &ProtocolError{"bad scheme"}
ErrBadStatus = &ProtocolError{"bad status"}
ErrBadUpgrade = &ProtocolError{"missing or bad upgrade"}
ErrBadWebSocketOrigin = &ProtocolError{"missing or bad WebSocket-Origin"}
ErrBadWebSocketLocation = &ProtocolError{"missing or bad WebSocket-Location"}
ErrBadWebSocketProtocol = &ProtocolError{"missing or bad WebSocket-Protocol"}
ErrBadWebSocketVersion = &ProtocolError{"missing or bad WebSocket Version"}
ErrChallengeResponse = &ProtocolError{"mismatch challenge/response"}
ErrBadFrame = &ProtocolError{"bad frame"}
ErrBadFrameBoundary = &ProtocolError{"not on frame boundary"}
ErrNotWebSocket = &ProtocolError{"not websocket protocol"}
ErrBadRequestMethod = &ProtocolError{"bad method"}
ErrNotSupported = &ProtocolError{"not supported"}
)
// ErrFrameTooLarge is returned by Codec's Receive method if payload size
// exceeds limit set by Conn.MaxPayloadBytes
var ErrFrameTooLarge = errors.New("websocket: frame payload size exceeds limit")
// Addr is an implementation of net.Addr for WebSocket.
type Addr struct {
*url.URL
}
// Network returns the network type for a WebSocket, "websocket".
func (addr *Addr) Network() string { return "websocket" }
// Config is a WebSocket configuration
type Config struct {
// A WebSocket server address.
Location *url.URL
// A Websocket client origin.
Origin *url.URL
// WebSocket subprotocols.
Protocol []string
// WebSocket protocol version.
Version int
// TLS config for secure WebSocket (wss).
TlsConfig *tls.Config
// Additional header fields to be sent in WebSocket opening handshake.
Header http.Header
// Dialer used when opening websocket connections.
Dialer *net.Dialer
handshakeData map[string]string
}
// serverHandshaker is an interface to handle WebSocket server side handshake.
type serverHandshaker interface {
// ReadHandshake reads handshake request message from client.
// Returns http response code and error if any.
ReadHandshake(buf *bufio.Reader, req *http.Request) (code int, err error)
// AcceptHandshake accepts the client handshake request and sends
// handshake response back to client.
AcceptHandshake(buf *bufio.Writer) (err error)
// NewServerConn creates a new WebSocket connection.
NewServerConn(buf *bufio.ReadWriter, rwc io.ReadWriteCloser, request *http.Request) (conn *Conn)
}
// frameReader is an interface to read a WebSocket frame.
type frameReader interface {
// Reader is to read payload of the frame.
io.Reader
// PayloadType returns payload type.
PayloadType() byte
// HeaderReader returns a reader to read header of the frame.
HeaderReader() io.Reader
// TrailerReader returns a reader to read trailer of the frame.
// If it returns nil, there is no trailer in the frame.
TrailerReader() io.Reader
// Len returns total length of the frame, including header and trailer.
Len() int
}
// frameReaderFactory is an interface to creates new frame reader.
type frameReaderFactory interface {
NewFrameReader() (r frameReader, err error)
}
// frameWriter is an interface to write a WebSocket frame.
type frameWriter interface {
// Writer is to write payload of the frame.
io.WriteCloser
}
// frameWriterFactory is an interface to create new frame writer.
type frameWriterFactory interface {
NewFrameWriter(payloadType byte) (w frameWriter, err error)
}
type frameHandler interface {
HandleFrame(frame frameReader) (r frameReader, err error)
WriteClose(status int) (err error)
}
// Conn represents a WebSocket connection.
//
// Multiple goroutines may invoke methods on a Conn simultaneously.
type Conn struct {
config *Config
request *http.Request
buf *bufio.ReadWriter
rwc io.ReadWriteCloser
rio sync.Mutex
frameReaderFactory
frameReader
wio sync.Mutex
frameWriterFactory
frameHandler
PayloadType byte
defaultCloseStatus int
// MaxPayloadBytes limits the size of frame payload received over Conn
// by Codec's Receive method. If zero, DefaultMaxPayloadBytes is used.
MaxPayloadBytes int
}
// Read implements the io.Reader interface:
// it reads data of a frame from the WebSocket connection.
// if msg is not large enough for the frame data, it fills the msg and next Read
// will read the rest of the frame data.
// it reads Text frame or Binary frame.
func (ws *Conn) Read(msg []byte) (n int, err error) {
ws.rio.Lock()
defer ws.rio.Unlock()
again:
if ws.frameReader == nil {
frame, err := ws.frameReaderFactory.NewFrameReader()
if err != nil {
return 0, err
}
ws.frameReader, err = ws.frameHandler.HandleFrame(frame)
if err != nil {
return 0, err
}
if ws.frameReader == nil {
goto again
}
}
n, err = ws.frameReader.Read(msg)
if err == io.EOF {
if trailer := ws.frameReader.TrailerReader(); trailer != nil {
io.Copy(ioutil.Discard, trailer)
}
ws.frameReader = nil
goto again
}
return n, err
}
// Write implements the io.Writer interface:
// it writes data as a frame to the WebSocket connection.
func (ws *Conn) Write(msg []byte) (n int, err error) {
ws.wio.Lock()
defer ws.wio.Unlock()
w, err := ws.frameWriterFactory.NewFrameWriter(ws.PayloadType)
if err != nil {
return 0, err
}
n, err = w.Write(msg)
w.Close()
return n, err
}
// Close implements the io.Closer interface.
func (ws *Conn) Close() error {
err := ws.frameHandler.WriteClose(ws.defaultCloseStatus)
err1 := ws.rwc.Close()
if err != nil {
return err
}
return err1
}
func (ws *Conn) IsClientConn() bool { return ws.request == nil }
func (ws *Conn) IsServerConn() bool { return ws.request != nil }
// LocalAddr returns the WebSocket Origin for the connection for client, or
// the WebSocket location for server.
func (ws *Conn) LocalAddr() net.Addr {
if ws.IsClientConn() {
return &Addr{ws.config.Origin}
}
return &Addr{ws.config.Location}
}
// RemoteAddr returns the WebSocket location for the connection for client, or
// the Websocket Origin for server.
func (ws *Conn) RemoteAddr() net.Addr {
if ws.IsClientConn() {
return &Addr{ws.config.Location}
}
return &Addr{ws.config.Origin}
}
var errSetDeadline = errors.New("websocket: cannot set deadline: not using a net.Conn")
// SetDeadline sets the connection's network read & write deadlines.
func (ws *Conn) SetDeadline(t time.Time) error {
if conn, ok := ws.rwc.(net.Conn); ok {
return conn.SetDeadline(t)
}
return errSetDeadline
}
// SetReadDeadline sets the connection's network read deadline.
func (ws *Conn) SetReadDeadline(t time.Time) error {
if conn, ok := ws.rwc.(net.Conn); ok {
return conn.SetReadDeadline(t)
}
return errSetDeadline
}
// SetWriteDeadline sets the connection's network write deadline.
func (ws *Conn) SetWriteDeadline(t time.Time) error {
if conn, ok := ws.rwc.(net.Conn); ok {
return conn.SetWriteDeadline(t)
}
return errSetDeadline
}
// Config returns the WebSocket config.
func (ws *Conn) Config() *Config { return ws.config }
// Request returns the http request upgraded to the WebSocket.
// It is nil for client side.
func (ws *Conn) Request() *http.Request { return ws.request }
// Codec represents a symmetric pair of functions that implement a codec.
type Codec struct {
Marshal func(v interface{}) (data []byte, payloadType byte, err error)
Unmarshal func(data []byte, payloadType byte, v interface{}) (err error)
}
// Send sends v marshaled by cd.Marshal as single frame to ws.
func (cd Codec) Send(ws *Conn, v interface{}) (err error) {
data, payloadType, err := cd.Marshal(v)
if err != nil {
return err
}
ws.wio.Lock()
defer ws.wio.Unlock()
w, err := ws.frameWriterFactory.NewFrameWriter(payloadType)
if err != nil {
return err
}
_, err = w.Write(data)
w.Close()
return err
}
// Receive receives single frame from ws, unmarshaled by cd.Unmarshal and stores
// in v. The whole frame payload is read to an in-memory buffer; max size of
// payload is defined by ws.MaxPayloadBytes. If frame payload size exceeds
// limit, ErrFrameTooLarge is returned; in this case frame is not read off wire
// completely. The next call to Receive would read and discard leftover data of
// previous oversized frame before processing next frame.
func (cd Codec) Receive(ws *Conn, v interface{}) (err error) {
ws.rio.Lock()
defer ws.rio.Unlock()
if ws.frameReader != nil {
_, err = io.Copy(ioutil.Discard, ws.frameReader)
if err != nil {
return err
}
ws.frameReader = nil
}
again:
frame, err := ws.frameReaderFactory.NewFrameReader()
if err != nil {
return err
}
frame, err = ws.frameHandler.HandleFrame(frame)
if err != nil {
return err
}
if frame == nil {
goto again
}
maxPayloadBytes := ws.MaxPayloadBytes
if maxPayloadBytes == 0 {
maxPayloadBytes = DefaultMaxPayloadBytes
}
if hf, ok := frame.(*hybiFrameReader); ok && hf.header.Length > int64(maxPayloadBytes) {
// payload size exceeds limit, no need to call Unmarshal
//
// set frameReader to current oversized frame so that
// the next call to this function can drain leftover
// data before processing the next frame
ws.frameReader = frame
return ErrFrameTooLarge
}
payloadType := frame.PayloadType()
data, err := ioutil.ReadAll(frame)
if err != nil {
return err
}
return cd.Unmarshal(data, payloadType, v)
}
func marshal(v interface{}) (msg []byte, payloadType byte, err error) {
switch data := v.(type) {
case string:
return []byte(data), TextFrame, nil
case []byte:
return data, BinaryFrame, nil
}
return nil, UnknownFrame, ErrNotSupported
}
func unmarshal(msg []byte, payloadType byte, v interface{}) (err error) {
switch data := v.(type) {
case *string:
*data = string(msg)
return nil
case *[]byte:
*data = msg
return nil
}
return ErrNotSupported
}
/*
Message is a codec to send/receive text/binary data in a frame on WebSocket connection.
To send/receive text frame, use string type.
To send/receive binary frame, use []byte type.
Trivial usage:
import "websocket"
// receive text frame
var message string
websocket.Message.Receive(ws, &message)
// send text frame
message = "hello"
websocket.Message.Send(ws, message)
// receive binary frame
var data []byte
websocket.Message.Receive(ws, &data)
// send binary frame
data = []byte{0, 1, 2}
websocket.Message.Send(ws, data)
*/
var Message = Codec{marshal, unmarshal}
func jsonMarshal(v interface{}) (msg []byte, payloadType byte, err error) {
msg, err = json.Marshal(v)
return msg, TextFrame, err
}
func jsonUnmarshal(msg []byte, payloadType byte, v interface{}) (err error) {
return json.Unmarshal(msg, v)
}
/*
JSON is a codec to send/receive JSON data in a frame from a WebSocket connection.
Trivial usage:
import "websocket"
type T struct {
Msg string
Count int
}
// receive JSON type T
var data T
websocket.JSON.Receive(ws, &data)
// send JSON type T
websocket.JSON.Send(ws, data)
*/
var JSON = Codec{jsonMarshal, jsonUnmarshal}