func (a *aggregator) attach(name string, ret libswarm.Sender) error {
if name != "" {
// TODO: implement this?
return fmt.Errorf("attaching to a child is not implemented")
}
if _, err := ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: a.server}); err != nil {
return err
}
var copies sync.WaitGroup
for _, b := range a.backends {
r, _, err := b.Attach("")
if err != nil {
return err
}
copies.Add(1)
go func() {
log.Printf("copying output from %#v\n", b)
libswarm.Copy(ret, r)
log.Printf("finished output from %#v\n", b)
copies.Done()
}()
}
copies.Wait()
return nil
}
func EncodeStream(sender libswarm.Sender, reader io.Reader, tag string) {
chunk := make([]byte, 4096)
for {
n, err := reader.Read(chunk)
if n > 0 {
sender.Send(&libswarm.Message{Verb: libswarm.Log, Args: []string{tag, string(chunk[0:n])}})
}
if err != nil {
message := fmt.Sprintf("Error reading from stream: %v", err)
sender.Send(&libswarm.Message{Verb: libswarm.Error, Args: []string{message}})
break
}
}
}
func (c *container) attach(name string, ret libswarm.Sender) error {
if _, err := ret.Send(&libswarm.Message{Verb: libswarm.Ack}); err != nil {
return err
}
path := fmt.Sprintf("/containers/%s/attach?stdout=1&stderr=1&stream=1", c.id)
stdoutR, stdoutW := io.Pipe()
stderrR, stderrW := io.Pipe()
go utils.EncodeStream(ret, stdoutR, "stdout")
go utils.EncodeStream(ret, stderrR, "stderr")
c.backend.client.hijack("POST", path, nil, stdoutW, stderrW)
return nil
}
func (b *dockerClientBackend) attach(name string, ret libswarm.Sender) error {
if name == "" {
ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: b.Server})
<-make(chan struct{})
} else {
path := fmt.Sprintf("/containers/%s/json", name)
resp, err := b.client.call("GET", path, "")
if err != nil {
return err
}
respBody, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
if resp.StatusCode != 200 {
return fmt.Errorf("%s", respBody)
}
c := b.newContainer(name)
ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: c})
}
return nil
}