コマンドの実行結果を JSON で返す郷

cmdRunner.go

package main

import (
    "fmt"
    "log"
    "os"
    "os/exec"
    "time"
    "flag"
    "encoding/json"
    "strings"
)

var (
    argCommand = flag.String("command", "", "Specify a Command.")
    argTimes = flag.Int("times", 1, "Specify a Loop Counts Number.")
    argInterval = flag.Int("interval", 3, "Specify a Wait Interval Times.")
)

type OutputMessages struct {
    Outputs []string    `json:"outputs"`
}

func runCommand(command string) (output string){
    cmd := exec.Command("sh", "-c", command)
    result, err := cmd.CombinedOutput()
    output = strings.TrimRight(string(result), "\n")
    if err != nil {
        // fmt.Println(err)
        errMessage := err.Error() + ": " + output
        log.Printf(string(errMessage))
        return output
    }
    return output
}

func main() {
    flag.Parse()
    if *argCommand == "" {
        fmt.Println("Please specify `-command` option.")
        os.Exit(1)
    }

    var stdout string
    var stdouts []string

    for i := 1; i <= *argTimes; i++ {
        stdout = runCommand(*argCommand)
        time.Sleep(time.Duration(*argInterval) * time.Second)
        stdouts = append(stdouts, stdout)
    }
    outputMessage := OutputMessages{Outputs: []string(stdouts)}
    jsonBytes, err := json.Marshal(outputMessage)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }
    fmt.Println(string(jsonBytes))
}