Merge pull request #34929 from stevvooe/remove-promise-package

pkg/package: remove promise package

container/stream/attach.go

@@ -7,7 +7,6 @@ import (
 	"golang.org/x/net/context"
 
 	"github.com/docker/docker/pkg/pools"
-	"github.com/docker/docker/pkg/promise"
 	"github.com/docker/docker/pkg/term"
 	"github.com/sirupsen/logrus"
 )
@@ -58,7 +57,7 @@ func (c *Config) AttachStreams(cfg *AttachConfig) {
 }
 
 // CopyStreams starts goroutines to copy data in and out to/from the container
-func (c *Config) CopyStreams(ctx context.Context, cfg *AttachConfig) chan error {
+func (c *Config) CopyStreams(ctx context.Context, cfg *AttachConfig) <-chan error {
 	var (
 		wg     sync.WaitGroup
 		errors = make(chan error, 3)
@@ -137,35 +136,42 @@ func (c *Config) CopyStreams(ctx context.Context, cfg *AttachConfig) chan error
 	go attachStream("stdout", cfg.Stdout, cfg.CStdout)
 	go attachStream("stderr", cfg.Stderr, cfg.CStderr)
 
-	return promise.Go(func() error {
-		done := make(chan struct{})
-		go func() {
-			wg.Wait()
-			close(done)
+	errs := make(chan error, 1)
+
+	go func() {
+		defer close(errs)
+		errs <- func() error {
+			done := make(chan struct{})
+			go func() {
+				wg.Wait()
+				close(done)
+			}()
+			select {
+			case <-done:
+			case <-ctx.Done():
+				// close all pipes
+				if cfg.CStdin != nil {
+					cfg.CStdin.Close()
+				}
+				if cfg.CStdout != nil {
+					cfg.CStdout.Close()
+				}
+				if cfg.CStderr != nil {
+					cfg.CStderr.Close()
+				}
+				<-done
+			}
+			close(errors)
+			for err := range errors {
+				if err != nil {
+					return err
+				}
+			}
+			return nil
 		}()
-		select {
-		case <-done:
-		case <-ctx.Done():
-			// close all pipes
-			if cfg.CStdin != nil {
-				cfg.CStdin.Close()
-			}
-			if cfg.CStdout != nil {
-				cfg.CStdout.Close()
-			}
-			if cfg.CStderr != nil {
-				cfg.CStderr.Close()
-			}
-			<-done
-		}
-		close(errors)
-		for err := range errors {
-			if err != nil {
-				return err
-			}
-		}
-		return nil
-	})
+	}()
+
+	return errs
 }
 
 func copyEscapable(dst io.Writer, src io.ReadCloser, keys []byte) (written int64, err error) {

pkg/archive/archive.go

@@ -20,7 +20,6 @@ import (
 	"github.com/docker/docker/pkg/idtools"
 	"github.com/docker/docker/pkg/ioutils"
 	"github.com/docker/docker/pkg/pools"
-	"github.com/docker/docker/pkg/promise"
 	"github.com/docker/docker/pkg/system"
 	"github.com/sirupsen/logrus"
 )
@@ -1095,36 +1094,42 @@ func (archiver *Archiver) CopyFileWithTar(src, dst string) (err error) {
 	}
 
 	r, w := io.Pipe()
-	errC := promise.Go(func() error {
-		defer w.Close()
+	errC := make(chan error, 1)
 
-		srcF, err := os.Open(src)
-		if err != nil {
-			return err
-		}
-		defer srcF.Close()
+	go func() {
+		defer close(errC)
 
-		hdr, err := tar.FileInfoHeader(srcSt, "")
-		if err != nil {
-			return err
-		}
-		hdr.Name = filepath.Base(dst)
-		hdr.Mode = int64(chmodTarEntry(os.FileMode(hdr.Mode)))
+		errC <- func() error {
+			defer w.Close()
 
-		if err := remapIDs(archiver.IDMappingsVar, hdr); err != nil {
-			return err
-		}
+			srcF, err := os.Open(src)
+			if err != nil {
+				return err
+			}
+			defer srcF.Close()
 
-		tw := tar.NewWriter(w)
-		defer tw.Close()
-		if err := tw.WriteHeader(hdr); err != nil {
-			return err
-		}
-		if _, err := io.Copy(tw, srcF); err != nil {
-			return err
-		}
-		return nil
-	})
+			hdr, err := tar.FileInfoHeader(srcSt, "")
+			if err != nil {
+				return err
+			}
+			hdr.Name = filepath.Base(dst)
+			hdr.Mode = int64(chmodTarEntry(os.FileMode(hdr.Mode)))
+
+			if err := remapIDs(archiver.IDMappingsVar, hdr); err != nil {
+				return err
+			}
+
+			tw := tar.NewWriter(w)
+			defer tw.Close()
+			if err := tw.WriteHeader(hdr); err != nil {
+				return err
+			}
+			if _, err := io.Copy(tw, srcF); err != nil {
+				return err
+			}
+			return nil
+		}()
+	}()
 	defer func() {
 		if er := <-errC; err == nil && er != nil {
 			err = er

pkg/containerfs/archiver.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/idtools"
-	"github.com/docker/docker/pkg/promise"
 	"github.com/docker/docker/pkg/system"
 	"github.com/sirupsen/logrus"
 )
@@ -122,40 +121,45 @@ func (archiver *Archiver) CopyFileWithTar(src, dst string) (err error) {
 	}
 
 	r, w := io.Pipe()
-	errC := promise.Go(func() error {
-		defer w.Close()
+	errC := make(chan error, 1)
 
-		srcF, err := srcDriver.Open(src)
-		if err != nil {
-			return err
-		}
-		defer srcF.Close()
+	go func() {
+		defer close(errC)
+		errC <- func() error {
+			defer w.Close()
 
-		hdr, err := tar.FileInfoHeader(srcSt, "")
-		if err != nil {
-			return err
-		}
-		hdr.Name = dstDriver.Base(dst)
-		if dstDriver.OS() == "windows" {
-			hdr.Mode = int64(chmodTarEntry(os.FileMode(hdr.Mode)))
-		} else {
-			hdr.Mode = int64(os.FileMode(hdr.Mode))
-		}
+			srcF, err := srcDriver.Open(src)
+			if err != nil {
+				return err
+			}
+			defer srcF.Close()
 
-		if err := remapIDs(archiver.IDMappingsVar, hdr); err != nil {
-			return err
-		}
+			hdr, err := tar.FileInfoHeader(srcSt, "")
+			if err != nil {
+				return err
+			}
+			hdr.Name = dstDriver.Base(dst)
+			if dstDriver.OS() == "windows" {
+				hdr.Mode = int64(chmodTarEntry(os.FileMode(hdr.Mode)))
+			} else {
+				hdr.Mode = int64(os.FileMode(hdr.Mode))
+			}
 
-		tw := tar.NewWriter(w)
-		defer tw.Close()
-		if err := tw.WriteHeader(hdr); err != nil {
-			return err
-		}
-		if _, err := io.Copy(tw, srcF); err != nil {
-			return err
-		}
-		return nil
-	})
+			if err := remapIDs(archiver.IDMappingsVar, hdr); err != nil {
+				return err
+			}
+
+			tw := tar.NewWriter(w)
+			defer tw.Close()
+			if err := tw.WriteHeader(hdr); err != nil {
+				return err
+			}
+			if _, err := io.Copy(tw, srcF); err != nil {
+				return err
+			}
+			return nil
+		}()
+	}()
 	defer func() {
 		if er := <-errC; err == nil && er != nil {
 			err = er

pkg/promise/promise.go

@@ -1,11 +0,0 @@
-package promise
-
-// Go is a basic promise implementation: it wraps calls a function in a goroutine,
-// and returns a channel which will later return the function's return value.
-func Go(f func() error) chan error {
-	ch := make(chan error, 1)
-	go func() {
-		ch <- f()
-	}()
-	return ch
-}

pkg/promise/promise_test.go

@@ -1,25 +0,0 @@
-package promise
-
-import (
-	"errors"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-func TestGo(t *testing.T) {
-	errCh := Go(functionWithError)
-	er := <-errCh
-	require.EqualValues(t, "Error Occurred", er.Error())
-
-	noErrCh := Go(functionWithNoError)
-	er = <-noErrCh
-	require.Nil(t, er)
-}
-
-func functionWithError() (err error) {
-	return errors.New("Error Occurred")
-}
-func functionWithNoError() (err error) {
-	return nil
-}