Merge pull request #3476 from bhcleek/ansible-with-docker

fix docker builder with ansible provisioner
This commit is contained in:
Rickard von Essen 2016-09-12 13:56:28 +02:00 committed by GitHub
commit 10cba9795f
1 changed files with 47 additions and 148 deletions

View File

@ -2,7 +2,6 @@ package docker
import (
"archive/tar"
"bytes"
"fmt"
"io"
"io/ioutil"
@ -10,12 +9,10 @@ import (
"os"
"os/exec"
"path/filepath"
"strconv"
"strings"
"sync"
"syscall"
"time"
"github.com/ActiveState/tail"
"github.com/hashicorp/go-version"
"github.com/mitchellh/packer/packer"
)
@ -30,42 +27,35 @@ type Communicator struct {
}
func (c *Communicator) Start(remote *packer.RemoteCmd) error {
// Create a temporary file to store the output. Because of a bug in
// Docker, sometimes all the output doesn't properly show up. This
// file will capture ALL of the output, and we'll read that.
//
// https://github.com/dotcloud/docker/issues/2625
outputFile, err := ioutil.TempFile(c.HostDir, "cmd")
var cmd *exec.Cmd
if c.Config.Pty {
cmd = exec.Command("docker", "exec", "-i", "-t", c.ContainerId, "/bin/sh", "-c", fmt.Sprintf("(%s)", remote.Command))
} else {
cmd = exec.Command("docker", "exec", "-i", c.ContainerId, "/bin/sh", "-c", fmt.Sprintf("(%s)", remote.Command))
}
var (
stdin_w io.WriteCloser
err error
)
stdin_w, err = cmd.StdinPipe()
if err != nil {
return err
}
outputFile.Close()
// This file will store the exit code of the command once it is complete.
exitCodePath := outputFile.Name() + "-exit"
var cmd *exec.Cmd
if c.canExec() {
if c.Config.Pty {
cmd = exec.Command("docker", "exec", "-i", "-t", c.ContainerId, "/bin/sh")
} else {
cmd = exec.Command("docker", "exec", "-i", c.ContainerId, "/bin/sh")
}
} else {
cmd = exec.Command("docker", "attach", c.ContainerId)
}
stdin_w, err := cmd.StdinPipe()
stderr_r, err := cmd.StderrPipe()
if err != nil {
// We have to do some cleanup since run was never called
os.Remove(outputFile.Name())
os.Remove(exitCodePath)
return err
}
stdout_r, err := cmd.StdoutPipe()
if err != nil {
return err
}
// Run the actual command in a goroutine so that Start doesn't block
go c.run(cmd, remote, stdin_w, outputFile, exitCodePath)
go c.run(cmd, remote, stdin_w, stdout_r, stderr_r)
return nil
}
@ -237,105 +227,51 @@ func (c *Communicator) DownloadDir(src string, dst string, exclude []string) err
return fmt.Errorf("DownloadDir is not implemented for docker")
}
// canExec tells us whether `docker exec` is supported
func (c *Communicator) canExec() bool {
execConstraint, err := version.NewConstraint(">= 1.4.0")
if err != nil {
panic(err)
}
return execConstraint.Check(c.Version)
}
// Runs the given command and blocks until completion
func (c *Communicator) run(cmd *exec.Cmd, remote *packer.RemoteCmd, stdin_w io.WriteCloser, outputFile *os.File, exitCodePath string) {
func (c *Communicator) run(cmd *exec.Cmd, remote *packer.RemoteCmd, stdin io.WriteCloser, stdout, stderr io.ReadCloser) {
// For Docker, remote communication must be serialized since it
// only supports single execution.
c.lock.Lock()
defer c.lock.Unlock()
// Clean up after ourselves by removing our temporary files
defer os.Remove(outputFile.Name())
defer os.Remove(exitCodePath)
// Tail the output file and send the data to the stdout listener
tail, err := tail.TailFile(outputFile.Name(), tail.Config{
Poll: true,
ReOpen: true,
Follow: true,
})
if err != nil {
log.Printf("Error tailing output file: %s", err)
remote.SetExited(254)
return
wg := sync.WaitGroup{}
repeat := func(w io.Writer, r io.ReadCloser) {
io.Copy(w, r)
r.Close()
wg.Done()
}
defer tail.Stop()
// Modify the remote command so that all the output of the commands
// go to a single file and so that the exit code is redirected to
// a single file. This lets us determine both when the command
// is truly complete (because the file will have data), what the
// exit status is (because Docker loses it because of the pty, not
// Docker's fault), and get the output (Docker bug).
remoteCmd := fmt.Sprintf("(%s) >%s 2>&1; echo $? >%s",
remote.Command,
filepath.Join(c.ContainerDir, filepath.Base(outputFile.Name())),
filepath.Join(c.ContainerDir, filepath.Base(exitCodePath)))
if remote.Stdout != nil {
wg.Add(1)
go repeat(remote.Stdout, stdout)
}
if remote.Stderr != nil {
wg.Add(1)
go repeat(remote.Stderr, stderr)
}
// Start the command
log.Printf("Executing in container %s: %#v", c.ContainerId, remoteCmd)
log.Printf("Executing %s:", strings.Join(cmd.Args, " "))
if err := cmd.Start(); err != nil {
log.Printf("Error executing: %s", err)
remote.SetExited(254)
return
}
go func() {
defer stdin_w.Close()
// This sleep needs to be here because of the issue linked to below.
// Basically, without it, Docker will hang on reading stdin forever,
// and won't see what we write, for some reason.
//
// https://github.com/dotcloud/docker/issues/2628
time.Sleep(2 * time.Second)
stdin_w.Write([]byte(remoteCmd + "\n"))
}()
// Start a goroutine to read all the lines out of the logs. These channels
// allow us to stop the go-routine and wait for it to be stopped.
stopTailCh := make(chan struct{})
doneCh := make(chan struct{})
go func() {
defer close(doneCh)
for {
select {
case <-tail.Dead():
return
case line := <-tail.Lines:
if remote.Stdout != nil {
remote.Stdout.Write([]byte(line.Text + "\n"))
} else {
log.Printf("Command stdout: %#v", line.Text)
}
case <-time.After(2 * time.Second):
// If we're done, then return. Otherwise, keep grabbing
// data. This gives us a chance to flush all the lines
// out of the tailed file.
select {
case <-stopTailCh:
return
default:
}
}
}
}()
var exitRaw []byte
var exitStatus int
var exitStatusRaw int64
err = cmd.Wait()
if remote.Stdin != nil {
go func() {
io.Copy(stdin, remote.Stdin)
// close stdin to support commands that wait for stdin to be closed before exiting.
stdin.Close()
}()
}
wg.Wait()
err := cmd.Wait()
if exitErr, ok := err.(*exec.ExitError); ok {
exitStatus = 1
@ -344,45 +280,8 @@ func (c *Communicator) run(cmd *exec.Cmd, remote *packer.RemoteCmd, stdin_w io.W
if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
exitStatus = status.ExitStatus()
}
// Say that we ended, since if Docker itself failed, then
// the command must've not run, or so we assume
goto REMOTE_EXIT
}
// Wait for the exit code to appear in our file...
log.Println("Waiting for exit code to appear for remote command...")
for {
fi, err := os.Stat(exitCodePath)
if err == nil && fi.Size() > 0 {
break
}
time.Sleep(1 * time.Second)
}
// Read the exit code
exitRaw, err = ioutil.ReadFile(exitCodePath)
if err != nil {
log.Printf("Error executing: %s", err)
exitStatus = 254
goto REMOTE_EXIT
}
exitStatusRaw, err = strconv.ParseInt(string(bytes.TrimSpace(exitRaw)), 10, 0)
if err != nil {
log.Printf("Error executing: %s", err)
exitStatus = 254
goto REMOTE_EXIT
}
exitStatus = int(exitStatusRaw)
log.Printf("Executed command exit status: %d", exitStatus)
REMOTE_EXIT:
// Wait for the tail to finish
close(stopTailCh)
<-doneCh
// Set the exit status which triggers waiters
remote.SetExited(exitStatus)
}