使用golang
调用阻塞式shell
命令(如ping
、tail -f
等),按普通的调用方法是无法拿到实时输出结果的,这里可以通过异步读取管道输出数据的方式实现,关键代码如下:
// command.go
package command
import (
"bufio"
"io"
"log"
"os/exec"
"runtime/debug"
"sync"
)
func readLine(wg *sync.WaitGroup, out chan string, reader io.ReadCloser) {
defer func() {
if r := recover(); r != nil {
log.Println(r, string(debug.Stack()))
}
}()
defer wg.Done()
r := bufio.NewReader(reader)
for {
line, _, err := r.ReadLine()
if err == io.EOF || err != nil {
return
}
out <- string(line)
}
}
// ExecCommandRealTimeOutput 读取命令行实时输出
// Exec command and read real time output
func ExecCommandRealTimeOutput(out chan string, name string, arg ...string) error {
cmd := exec.Command(name, arg...)
stdout, _ := cmd.StdoutPipe()
stderr, _ := cmd.StderrPipe()
if err := cmd.Start(); err != nil {
return err
}
wg := sync.WaitGroup{}
defer wg.Wait()
wg.Add(2)
go readLine(&wg, out, stdout)
go readLine(&wg, out, stderr)
if err := cmd.Wait(); err != nil {
return err
}
return nil
}
测试用例:
// command_test.go
package command
import (
"log"
"testing"
)
func TestExecCommandRealTimeOutput(t *testing.T) {
out := make(chan string)
defer close(out)
go func() {
for {
str, ok := <-out
if !ok {
break
}
log.Println(str)
}
}()
args := []string{"-c", "ping www.trumanwl.com"}
if err := ExecCommandRealTimeOutput(out, "bash", args...); err != nil {
t.Error(err)
}
}
测试:
$ go test -v command_test.go command.go
=== RUN TestExecCommandRealTimeOutput
2023/06/14 14:54:51 PING cname.vercel-dns.com (76.76.21.22) 56(84) bytes of data.
2023/06/14 14:54:51 64 bytes from 76.76.21.22 (76.76.21.22): icmp_seq=1 ttl=128 time=55.7 ms
2023/06/14 14:54:52 64 bytes from 76.76.21.22 (76.76.21.22): icmp_seq=2 ttl=128 time=74.6 ms
2023/06/14 14:54:53 64 bytes from 76.76.21.22 (76.76.21.22): icmp_seq=3 ttl=128 time=63.1 ms
2023/06/14 14:54:54 64 bytes from 76.76.21.22 (76.76.21.22): icmp_seq=4 ttl=128 time=63.8 ms
2023/06/14 14:54:55 64 bytes from 76.76.21.22 (76.76.21.22): icmp_seq=5 ttl=128 time=56.6 ms
文中代码已推送至github