package docker import ( "fmt" "io" "log" "os/exec" "regexp" "strings" "sync" "syscall" "github.com/hashicorp/packer/packer" "github.com/mitchellh/iochan" ) func runAndStream(cmd *exec.Cmd, ui packer.Ui) error { stdout_r, stdout_w := io.Pipe() stderr_r, stderr_w := io.Pipe() defer stdout_w.Close() defer stderr_w.Close() args := make([]string, len(cmd.Args)-1) copy(args, cmd.Args[1:]) // Scrub password from the log output. for i, v := range args { if v == "-p" || v == "--password" { args[i+1] = "" break } } log.Printf("Executing: %s %v", cmd.Path, args) cmd.Stdout = stdout_w cmd.Stderr = stderr_w if err := cmd.Start(); err != nil { return err } // Create the channels we'll use for data exitCh := make(chan int, 1) stdoutCh := iochan.DelimReader(stdout_r, '\n') stderrCh := iochan.DelimReader(stderr_r, '\n') // Start the goroutine to watch for the exit go func() { defer stdout_w.Close() defer stderr_w.Close() exitStatus := 0 err := cmd.Wait() if exitErr, ok := err.(*exec.ExitError); ok { exitStatus = 1 // There is no process-independent way to get the REAL // exit status so we just try to go deeper. if status, ok := exitErr.Sys().(syscall.WaitStatus); ok { exitStatus = status.ExitStatus() } } exitCh <- exitStatus }() // This waitgroup waits for the streaming to end var streamWg sync.WaitGroup streamWg.Add(2) streamFunc := func(ch <-chan string) { defer streamWg.Done() for data := range ch { data = cleanOutputLine(data) if data != "" { ui.Message(data) } } } // Stream stderr/stdout go streamFunc(stderrCh) go streamFunc(stdoutCh) // Wait for the process to end and then wait for the streaming to end exitStatus := <-exitCh streamWg.Wait() if exitStatus != 0 { return fmt.Errorf("Bad exit status: %d", exitStatus) } return nil } // cleanOutputLine cleans up a line so that '\r' don't muck up the // UI output when we're reading from a remote command. func cleanOutputLine(line string) string { // Build a regular expression that will get rid of shell codes re := regexp.MustCompile("(?i)\x1b\\[([0-9]{1,2}(;[0-9]{1,2})?)?[a|b|m|k]") line = re.ReplaceAllString(line, "") // Trim surrounding whitespace line = strings.TrimSpace(line) // Trim up to the first carriage return, since that text would be // lost anyways. idx := strings.LastIndex(line, "\r") if idx > -1 { line = line[idx+1:] } return line }