-
Notifications
You must be signed in to change notification settings - Fork 3
/
waitfor.go
92 lines (84 loc) · 2.16 KB
/
waitfor.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
// Copyright 2019 github.com/ucirello
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"net/http"
"os"
"os/exec"
"os/signal"
"strings"
"time"
cli "github.com/urfave/cli"
)
func waitfor() {
app := cli.NewApp()
app.Name = "waitfor"
app.Usage = "probes the service discovery before running the given command"
app.HideVersion = true
app.Flags = []cli.Flag{
cli.StringFlag{
Name: "service-discovery",
Value: "localhost:64000",
Usage: "service discovery address",
},
}
app.Action = func(c *cli.Context) error {
sigint := make(chan os.Signal, 1)
signal.Notify(sigint, os.Interrupt)
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
go func() {
<-sigint
log.Println("shutting down")
cancel()
}()
for {
time.Sleep(250 * time.Millisecond)
resp, err := http.Get("http://" + c.String("service-discovery") + "/discovery")
if err != nil {
continue
}
defer resp.Body.Close()
var procs map[string]string // map of procType to state
if err := json.NewDecoder(resp.Body).Decode(&procs); err != nil {
return fmt.Errorf("cannot parse state of service discovery endpoint: %v", err)
}
allBuilt := true
for k, v := range procs {
if !strings.HasPrefix(k, "BUILD_") || v == "done" {
continue
}
allBuilt = false
break
}
if allBuilt {
break
}
}
cmd := strings.Join(c.Args(), " ")
cmdExec := exec.CommandContext(ctx, "sh", "-c", cmd)
cmdExec.Stdin = os.Stdin
cmdExec.Stderr = os.Stderr
cmdExec.Stdout = os.Stdout
cmdExec.Run()
return nil
}
if err := app.Run(os.Args); err != nil {
log.Fatal(err)
}
}