packer-cn/builder/lxd/command.go

44 lines
1.1 KiB
Go

package lxd
import (
"bytes"
"fmt"
"log"
"os/exec"
"strings"
)
// CommandWrapper is a type that given a command, will possibly modify that
// command in-flight. This might return an error.
type CommandWrapper func(string) (string, error)
// ShellCommand takes a command string and returns an *exec.Cmd to execute
// it within the context of a shell (/bin/sh).
func ShellCommand(command string) *exec.Cmd {
return exec.Command("/bin/sh", "-c", command)
}
// Yeah...LXD calls `lxc` because the command line is different between the
// packages. This should also avoid a naming collision between the LXC builder.
func LXDCommand(args ...string) (string, error) {
var stdout, stderr bytes.Buffer
log.Printf("Executing lxc command: %#v", args)
cmd := exec.Command("lxc", args...)
cmd.Stdout = &stdout
cmd.Stderr = &stderr
err := cmd.Run()
stdoutString := strings.TrimSpace(stdout.String())
stderrString := strings.TrimSpace(stderr.String())
if _, ok := err.(*exec.ExitError); ok {
err = fmt.Errorf("LXD command error: %s", stderrString)
}
log.Printf("stdout: %s", stdoutString)
log.Printf("stderr: %s", stderrString)
return stdoutString, err
}