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
|
package roadrunner
import (
"fmt"
"github.com/pkg/errors"
"github.com/spiral/goridge"
"net"
"os/exec"
"sync"
"time"
)
// SocketFactory connects to external workers using socket server.
type SocketFactory struct {
// listens for incoming connections from underlying processes
ls net.Listener
// relay connection timeout
tout time.Duration
// protects socket mapping
mu sync.Mutex
// sockets which are waiting for process association
relays map[int]chan *goridge.SocketRelay
}
// NewSocketFactory returns SocketFactory attached to a given socket listener.
// tout specifies for how long factory should serve for incoming relay connection
func NewSocketFactory(ls net.Listener, tout time.Duration) *SocketFactory {
f := &SocketFactory{
ls: ls,
tout: tout,
relays: make(map[int]chan *goridge.SocketRelay),
}
go f.listen()
return f
}
// SpawnWorker creates worker and connects it to appropriate relay or returns error
func (f *SocketFactory) SpawnWorker(cmd *exec.Cmd) (w *Worker, err error) {
if w, err = newWorker(cmd); err != nil {
return nil, err
}
if err := w.Start(); err != nil {
return nil, errors.Wrap(err, "process error")
}
rl, err := f.findRelay(w, f.tout)
if err != nil {
go func(w *Worker) { w.Kill() }(w)
if wErr := w.Wait(); wErr != nil {
err = errors.Wrap(wErr, err.Error())
}
return nil, errors.Wrap(err, "unable to connect to worker")
}
w.rl = rl
w.state.set(StateReady)
return w, nil
}
// listens for incoming socket connections
func (f *SocketFactory) listen() {
for {
conn, err := f.ls.Accept()
if err != nil {
return
}
rl := goridge.NewSocketRelay(conn)
if pid, err := fetchPID(rl); err == nil {
f.relayChan(pid) <- rl
}
}
}
// waits for worker to connect over socket and returns associated relay of timeout
func (f *SocketFactory) findRelay(w *Worker, tout time.Duration) (*goridge.SocketRelay, error) {
timer := time.NewTimer(tout)
for {
select {
case rl := <-f.relayChan(*w.Pid):
timer.Stop()
f.cleanChan(*w.Pid)
return rl, nil
case <-timer.C:
return nil, fmt.Errorf("relay timeout")
case <-w.waitDone:
timer.Stop()
f.cleanChan(*w.Pid)
return nil, fmt.Errorf("worker is gone")
}
}
}
// chan to store relay associated with specific Pid
func (f *SocketFactory) relayChan(pid int) chan *goridge.SocketRelay {
f.mu.Lock()
defer f.mu.Unlock()
rl, ok := f.relays[pid]
if !ok {
f.relays[pid] = make(chan *goridge.SocketRelay)
return f.relays[pid]
}
return rl
}
// deletes relay chan associated with specific Pid
func (f *SocketFactory) cleanChan(pid int) {
f.mu.Lock()
defer f.mu.Unlock()
delete(f.relays, pid)
}
|
