SSH to Vagrant instance with Golang

testssh.go

package main

import (
	"bytes"
	"fmt"
	"golang.org/x/crypto/ssh"
	"io/ioutil"
	"log"
	"os"
	"time"
)

func loadPrivateKey() (ssh.Signer, error) {
	pemBytes, err := ioutil.ReadFile(os.Getenv("HOME") + "/.vagrant.d/insecure_private_key")
	if err != nil {
		return nil, err
	}

	signer, err := ssh.ParsePrivateKey(pemBytes)
	if err != nil {
		return nil, err
	}

	return signer, nil
}

func executeCmd(cmd string, hostname string, config *ssh.ClientConfig) string {
	conn, err := ssh.Dial("tcp", hostname, config)
	if err != nil {
		log.Fatalf("dial failed:%v", err)
	}
	defer conn.Close()

	session, err := conn.NewSession()
	if err != nil {
		log.Fatalf("session failed:%v", err)
	}
	defer session.Close()

	var stdoutBuf bytes.Buffer
	session.Stdout = &stdoutBuf
	session.Run(cmd)

	return hostname + ": " + stdoutBuf.String()
}

func main() {
	hosts := []string{"localhost:2222", "localhost:2222"}

	signer, err := loadPrivateKey()
	if err != nil {
		log.Fatal(err)
	}

	config := &ssh.ClientConfig{
		User: "vagrant",
		Auth: []ssh.AuthMethod{ssh.PublicKeys(signer)},
	}

	results := make(chan string, 10)
	timeout := time.After(5 * time.Second)

	for _, hostname := range hosts {
		go func(hostname string) {
			results <- executeCmd("ls -l /projects", hostname, config)
		}(hostname)
	}

	for i := 0; i < len(hosts); i++ {
		select {
		case res := <-results:
			fmt.Print(res)
		case <-timeout:
			fmt.Println("Timed out!")
		}
	}
}