Initial commit

vendor/github.com/hyperhq/hypercli/runconfig/streams.go

@@ -0,0 +1,107 @@
+package runconfig
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"strings"
+
+	"github.com/hyperhq/hypercli/pkg/broadcaster"
+	"github.com/hyperhq/hypercli/pkg/ioutils"
+)
+
+// 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(nil)
+	streamConfig.stdout.Add(bytesPipe)
+	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(nil)
+	streamConfig.stderr.Add(bytesPipe)
+	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
+}