如何获取命令的输出

Question

我正在从 Go 代码调用 python 脚本：

package main
import (
    "os/exec"
    "os"
    "fmt"
    "time"
    "encoding/json"
)

func main() {
    cmd := exec.Command("python","/home/devendra/Desktop/sync/blur_multithread.py","http://4.imimg.com/data4/TP/ED/NSDMERP-28759633/audiovideojocks.png")
    var logs=make(map[string]interface{})
    logs["tes"]=os.Stdout
    _ = cmd.Run()   
    WriteLogs(logs)//Writelog is my function which logs everything in a file
}

func WriteLogs(logs map[string]interface{}){
  currentTime := time.Now().Local()
  jsonLog, err := json.Marshal(logs)
  if err != nil {
    fmt.Println(err.Error())
  }

  jsonLogString := string(jsonLog[:len(jsonLog)])
  logfile := "/home/devendra/ImageServiceLogs/"+ "ImageServiceLogs_" + currentTime.Format("2006-01-02") + ".txt"
  if logfile == "" {
    fmt.Println("Could not find logfile in configuration ...!!!")
  } else {

    jsonLogFile, err := os.OpenFile(logfile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644)
    defer jsonLogFile.Close()
    if err != nil {
      fmt.Println(err.Error())
    }

    jsonLogFile.WriteString(jsonLogString + "\n")
  }
}

但是在我的 python 脚本给我输出时，tes 字段的日志值是空的。如何在我的代码中获取 python 脚本的输出？

Answer 1

根据官方文档示例，exec.Cmd.Ouput() ([]byte, error) 将在命令完成后为您提供命令的 sdout 运行。

https://golang.org/pkg/os/exec/#Cmd.Output

package main

import (
    "fmt"
    "log"
    "os/exec"
)

func main() {
    out, err := exec.Command("date").Output()
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("The date is %s\n", out)
}

要同时接收进程的 stdout 和 stderr，作者应该使用 exec.Cmd.CombinedOutput https://golang.org/pkg/os/exec/#Cmd.CombinedOutput

如果有人想实时接收命令输出到它的终端，那么编写者应该将exec.Cmd.Stdout和exec.Cmd.Stderr属性分别设置为os.Stdout和[=18] =] 并调用 exec.Cmd.Run() error 方法。

https://golang.org/pkg/os/exec/#Cmd https://golang.org/pkg/os/exec/#Cmd.Run

package main

import (
    "fmt"
    "log"
    "os"
    "os/exec"
)

func main() {
    cmd := exec.Command("date")
    cmd.Stdout = os.Stdout
    cmd.Stderr = os.Stderr
    err := cmd.Run()
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("The date is %s\n", out)
}

要转发输出并同时捕获它，作者应该寻求 io 包的帮助以使用 io.MultiWriter

https://golang.org/pkg/io/#MultiWriter

package main

import (
    "fmt"
    "io"
    "log"
    "os"
    "os/exec"
)

func main() {
    stdout := new(bytes.Bufer)
    stderr := new(bytes.Bufer)
    cmd := exec.Command("date")
    cmd.Stdout = io.MultiWriter(os.Stdout, stdout)
    cmd.Stderr = io.MultiWriter(os.Stderr, stderr)
    err := cmd.Run()
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("The date is %s\n", out)
}

或者，您可以使用 exec.Cmd.{Stdout,Stderr}Pipe() 查看官方文档示例 https://golang.org/pkg/os/exec/#Cmd.StdoutPipe

如何获取命令的输出

How to get the output of a command

exec

go