/
connection.go
216 lines (188 loc) · 5.23 KB
/
connection.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
package webchan
import (
"log"
"time"
"net/http"
"io/ioutil"
"github.com/garyburd/go-websocket/websocket"
)
const (
// Time allowed to write a message to the client.
writeWait = 10 * time.Second
// Time allowed to read the next message from the client.
readWait = 60 * time.Second
// Send pings to client with this period. Must be less than readWait.
pingPeriod = (readWait * 9) / 10
// Maximum message size allowed from client.
maxMessageSize = 512
)
// connection is an middleman between the websocket connection and the hub.
type connection struct {
// sessionId
SessionId string
// channel
ChannelName string
// The websocket connection.
ws *websocket.Conn
// Buffered channel of outbound messages.
send chan []byte
}
// interface method
func (c *connection) Channel() string {
return c.ChannelName
}
func (c *connection) UniqId() string {
return c.SessionId
}
// readPump pumps messages from the websocket connection to the hub.
func (c *connection) readPump() {
defer func() {
h.unregister <- c
c.ws.Close()
}()
c.ws.SetReadLimit(maxMessageSize)
c.ws.SetReadDeadline(time.Now().Add(readWait))
welcomeMsg := &WelcomeMsg{}
welcomeb,err := welcomeMsg.Marshal(c.SessionId)
if err != nil {
log.Error("could not create welcome message: %s",err)
return
}
c.send <- welcomeb
for {
op, r, err := c.ws.NextReader()
if err != nil {
break
}
switch op {
case websocket.OpPong:
c.ws.SetReadDeadline(time.Now().Add(readWait))
case websocket.OpText:
message, err := ioutil.ReadAll(r)
if err != nil {
break
}
var data []interface{}
err := json.Unmarshal(message,&data)
if err != nil {
break
}
c.handleMessage(data)
}
}
}
// 解析message 成对应的struct
// 创建channel 和 connection的对应关系
func (c *connection)handleMessage(message []interface{}) error {
var typeid int
if typeid,ok := message[0].(int); !ok {
return
}
switch typeid {
case SUBSCRIBE:
subscribeMsg := &SubscribeMsg{}
if err := subscribeMsg.UnmarshalJSON(message); err {
return
}
c.handleSubscribe(subscribeMsg)
case UNSUBSCRIBE:
unsubscribeMsg := &UnsubscribeMsg{}
if err := unsubscribeMsg.UnmarshalJSON(message); err {
return
}
c.handleUnsubscribe(unsubscribeMsg)
case PUBLISH:
publishMsg := &PublishMsg{}
if err := publishMsg.UnmarshalJSON(message); err {
return
}
c.handlePublish(publishMsg)
}
}
func (c *connection)handleSubscribe(msg *SubscribeMsg ) {
if HUB.unsubscribeConns[c] {
HUB.mu.Lock()
delete(HUB.unsubscirbeConns,c)
HUB.mu.Unlock()
}
if c.Channel() {
HUB.storeLock.Lock()
HUB.connStore.DelConn(c)
HUB.storeLock.Unlock()
}
c.ChannelName = msg.Channel
HUB.storeLock.Lock()
HUB.connStore.AddConn(c)
HUB.storeLock.Unlock()
}
func (c *connection)handleUnsubcribe(msg *UnsubscribeMsg){
if c.Channel() == msg.Channel {
HUB.storeLock.Lock()
HUB.connStore.DelConn(c)
HUB.storeLock.Unlock()
}
}
func (c *connection)handlePublish(msg *PublishMsg){
if c.Channel() != msg.Channel {
return
}
eventMsg := &EventMsg{Channel:msg.Channel,Event:msg.Event,Data:msg.Data}
HUB.event <- eventMsg
}
// write writes a message with the given opCode and payload.
func (c *connection) write(opCode int, payload []byte) error {
c.ws.SetWriteDeadline(time.Now().Add(writeWait))
return c.ws.WriteMessage(opCode, payload)
}
// writePump pumps messages from the hub to the websocket connection.
func (c *connection) writePump() {
ticker := time.NewTicker(pingPeriod)
defer func() {
ticker.Stop()
c.ws.Close()
}()
for {
select {
case message, ok := <-c.send:
if !ok {
c.write(websocket.OpClose, []byte{})
return
}
if err := c.write(websocket.OpText, message); err != nil {
return
}
case <-ticker.C:
if err := c.write(websocket.OpPing, []byte{}); err != nil {
return
}
}
}
}
func ServeRequest(w http.ResponseWriter, r *http.Request){
if r.Method != "GET" {
http.Error(w,"Method not allowed",405)
return
}
if r.Header.Get("Origin") != "http://" + r.Host {
http.Error(w,"Origin not allowed",403)
return
}
ws,err := websocket.Upgrade(w,r.Header,nil,1024,1024)
if _,ok := err.(websocket.HandshakeError); ok {
http.Error(w,"Not a websocket handshake",400)
return
} else if err != nil {
log.Println(err)
return
}
tid,err := uuid.NewV4()
if err != nil {
log.Error("could not create sessionid")
return
}
id := tid.String()
c := &connection{SessionId:id,send:make(chan []byte,256),ws:ws}
h.register <- c
go c.writePump()
c.readPump()
}