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
|
package wray
import (
"fmt"
"path/filepath"
"strings"
"time"
)
const (
UNCONNECTED = 1
CONNECTING = 2
CONNECTED = 3
DISCONNECTED = 4
HANDSHAKE = "handshake"
RETRY = "retry"
NONE = "none"
CONNECTION_TIMEOUT = 60.0
DEFAULT_RETRY = 5.0
MAX_REQUEST_SIZE = 2048
)
var (
MANDATORY_CONNECTION_TYPES = []string{"long-polling"}
registeredTransports = []Transport{}
)
type FayeClient struct {
state int
url string
subscriptions []Subscription
transport Transport
clientId string
schedular Schedular
}
type Subscription struct {
channel string
callback func(Message)
}
type SubscriptionPromise struct {
subscription Subscription
}
func NewFayeClient(url string) *FayeClient {
schedular := ChannelSchedular{}
client := &FayeClient{url: url, state: UNCONNECTED, schedular: schedular}
return client
}
func (self *FayeClient) handshake() {
t, err := SelectTransport(self, MANDATORY_CONNECTION_TYPES, []string{})
if err != nil {
panic("No usable transports available")
}
self.transport = t
self.transport.setUrl(self.url)
self.state = CONNECTING
handshakeParams := map[string]interface{}{"channel": "/meta/handshake",
"version": "1.0",
"supportedConnectionTypes": []string{"long-polling"}}
response, err := self.transport.send(handshakeParams)
if err != nil {
fmt.Println("Handshake failed. Retry in 10 seconds")
self.state = UNCONNECTED
self.schedular.wait(10*time.Second, func() {
fmt.Println("retying handshake")
self.handshake()
})
return
}
self.clientId = response.clientId
self.state = CONNECTED
self.transport, err = SelectTransport(self, response.supportedConnectionTypes, []string{})
if err != nil {
panic("Server does not support any available transports. Supported transports: " + strings.Join(response.supportedConnectionTypes, ","))
}
}
func (self *FayeClient) Subscribe(channel string, force bool, callback func(Message)) SubscriptionPromise {
if self.state == UNCONNECTED {
self.handshake()
}
subscriptionParams := map[string]interface{}{"channel": "/meta/subscribe", "clientId": self.clientId, "subscription": channel, "id": "1"}
subscription := Subscription{channel: channel, callback: callback}
//TODO: deal with subscription failures
self.transport.send(subscriptionParams)
self.subscriptions = append(self.subscriptions, subscription)
return SubscriptionPromise{subscription}
}
func (self *FayeClient) handleResponse(response Response) {
for _, message := range response.messages {
for _, subscription := range self.subscriptions {
matched, _ := filepath.Match(subscription.channel, message.Channel)
if matched {
go subscription.callback(message)
}
}
}
}
func (self *FayeClient) connect() {
connectParams := map[string]interface{}{"channel": "/meta/connect", "clientId": self.clientId, "connectionType": self.transport.connectionType()}
responseChannel := make(chan Response)
go func() {
response, _ := self.transport.send(connectParams)
responseChannel <- response
}()
self.listen(responseChannel)
}
func (self *FayeClient) listen(responseChannel chan Response) {
response := <-responseChannel
if response.successful == true {
go self.handleResponse(response)
} else {
}
}
func (self *FayeClient) Listen() {
for {
self.connect()
}
}
func (self *FayeClient) Publish(channel string, data map[string]interface{}) {
if self.state != CONNECTED {
self.handshake()
}
publishParams := map[string]interface{}{"channel": channel, "data": data, "clientId": self.clientId}
self.transport.send(publishParams)
}
func RegisterTransports(transports []Transport) {
registeredTransports = transports
}
|
