blob: 117fd89aee784066d69a9a9fa664d6d057fea264 [file] [log] [blame]
package runconfig
import (
// StreamConfig holds information about I/O streams managed together.
// streamConfig.StdinPipe returns a WriteCloser which can be used to feed data
// to the standard input of the streamConfig's active process.
// streamConfig.StdoutPipe and streamConfig.StderrPipe each return a ReadCloser
// which can be used to retrieve the standard output (and error) generated
// by the container's active process. The output (and error) are actually
// copied and delivered to all StdoutPipe and StderrPipe consumers, using
// a kind of "broadcaster".
type StreamConfig struct {
stdout *broadcaster.Unbuffered
stderr *broadcaster.Unbuffered
stdin io.ReadCloser
stdinPipe io.WriteCloser
// NewStreamConfig creates a stream config and initializes
// the standard err and standard out to new unbuffered broadcasters.
func NewStreamConfig() *StreamConfig {
return &StreamConfig{
stderr: new(broadcaster.Unbuffered),
stdout: new(broadcaster.Unbuffered),
// Stdout returns the standard output in the configuration.
func (streamConfig *StreamConfig) Stdout() *broadcaster.Unbuffered {
return streamConfig.stdout
// Stderr returns the standard error in the configuration.
func (streamConfig *StreamConfig) Stderr() *broadcaster.Unbuffered {
return streamConfig.stderr
// Stdin returns the standard input in the configuration.
func (streamConfig *StreamConfig) Stdin() io.ReadCloser {
return streamConfig.stdin
// StdinPipe returns an input writer pipe as an io.WriteCloser.
func (streamConfig *StreamConfig) StdinPipe() io.WriteCloser {
return streamConfig.stdinPipe
// StdoutPipe creates a new io.ReadCloser with an empty bytes pipe.
// It adds this new out pipe to the Stdout broadcaster.
func (streamConfig *StreamConfig) StdoutPipe() io.ReadCloser {
bytesPipe := ioutils.NewBytesPipe()
return bytesPipe
// StderrPipe creates a new io.ReadCloser with an empty bytes pipe.
// It adds this new err pipe to the Stderr broadcaster.
func (streamConfig *StreamConfig) StderrPipe() io.ReadCloser {
bytesPipe := ioutils.NewBytesPipe()
return bytesPipe
// NewInputPipes creates new pipes for both standard inputs, Stdin and StdinPipe.
func (streamConfig *StreamConfig) NewInputPipes() {
streamConfig.stdin, streamConfig.stdinPipe = io.Pipe()
// NewNopInputPipe creates a new input pipe that will silently drop all messages in the input.
func (streamConfig *StreamConfig) NewNopInputPipe() {
streamConfig.stdinPipe = ioutils.NopWriteCloser(ioutil.Discard)
// CloseStreams ensures that the configured streams are properly closed.
func (streamConfig *StreamConfig) CloseStreams() error {
var errors []string
if streamConfig.stdin != nil {
if err := streamConfig.stdin.Close(); err != nil {
errors = append(errors, fmt.Sprintf("error close stdin: %s", err))
if err := streamConfig.stdout.Clean(); err != nil {
errors = append(errors, fmt.Sprintf("error close stdout: %s", err))
if err := streamConfig.stderr.Clean(); err != nil {
errors = append(errors, fmt.Sprintf("error close stderr: %s", err))
if len(errors) > 0 {
return fmt.Errorf(strings.Join(errors, "\n"))
return nil