'docker push' shows an additional progress bar while it buffers the archive to disk. Fixes #451.

commands.go

@@ -475,7 +475,7 @@ func (srv *Server) CmdImport(stdin io.ReadCloser, stdout rcli.DockerConn, args .
 		if err != nil {
 			return err
 		}
-		archive = ProgressReader(resp.Body, int(resp.ContentLength), stdout)
+		archive = ProgressReader(resp.Body, int(resp.ContentLength), stdout, "Importing %v/%v (%v)")
 	}
 	img, err := srv.runtime.graph.Create(archive, nil, "Imported from "+src, "")
 	if err != nil {

graph.go

@@ -2,6 +2,7 @@ package docker
 
 import (
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"path"
@@ -131,7 +132,9 @@ func (graph *Graph) Register(layerData Archive, img *Image) error {
 
 // TempLayerArchive creates a temporary archive of the given image's filesystem layer.
 //   The archive is stored on disk and will be automatically deleted as soon as has been read.
-func (graph *Graph) TempLayerArchive(id string, compression Compression) (*TempArchive, error) {
+//   If output is not nil, a human-readable progress bar will be written to it.
+//   FIXME: does this belong in Graph? How about MktempFile, let the caller use it for archives?
+func (graph *Graph) TempLayerArchive(id string, compression Compression, output io.Writer) (*TempArchive, error) {
 	image, err := graph.Get(id)
 	if err != nil {
 		return nil, err
@@ -144,7 +147,7 @@ func (graph *Graph) TempLayerArchive(id string, compression Compression) (*TempA
 	if err != nil {
 		return nil, err
 	}
-	return NewTempArchive(archive, tmp.Root)
+	return NewTempArchive(ProgressReader(ioutil.NopCloser(archive), 0, output, "Buffering to disk %v/%v (%v)"), tmp.Root)
 }
 
 // Mktemp creates a temporary sub-directory inside the graph's filesystem.

registry.go

@@ -136,7 +136,7 @@ func (graph *Graph) getRemoteImage(stdout io.Writer, imgId string, authConfig *a
 	if err != nil {
 		return nil, nil, err
 	}
-	return img, ProgressReader(res.Body, int(res.ContentLength), stdout), nil
+	return img, ProgressReader(res.Body, int(res.ContentLength), stdout, "Downloading %v/%v (%v)"), nil
 }
 
 func (graph *Graph) PullImage(stdout io.Writer, imgId string, authConfig *auth.AuthConfig) error {
@@ -274,12 +274,12 @@ func (graph *Graph) PushImage(stdout io.Writer, imgOrig *Image, authConfig *auth
 		//	a) Implementing S3's proprietary streaming logic, or
 		//	b) Stream directly to the registry instead of S3.
 		// I prefer option b. because it doesn't lock us into a proprietary cloud service.
-		tmpLayer, err := graph.TempLayerArchive(img.Id, Xz)
+		tmpLayer, err := graph.TempLayerArchive(img.Id, Xz, stdout)
 		if err != nil {
 			return err
 		}
 		defer os.Remove(tmpLayer.Name())
-		req3, err := http.NewRequest("PUT", url.String(), ProgressReader(tmpLayer, int(tmpLayer.Size), stdout))
+		req3, err := http.NewRequest("PUT", url.String(), ProgressReader(tmpLayer, int(tmpLayer.Size), stdout, "Uploading %v/%v (%v)"))
 		if err != nil {
 			return err
 		}

utils.go

@@ -72,23 +72,30 @@ type progressReader struct {
 	readTotal    int           // Expected stream length (bytes)
 	readProgress int           // How much has been read so far (bytes)
 	lastUpdate   int           // How many bytes read at least update
+	template     string        // Template to print. Default "%v/%v (%v)"
 }
 
 func (r *progressReader) Read(p []byte) (n int, err error) {
 	read, err := io.ReadCloser(r.reader).Read(p)
 	r.readProgress += read
 
-	// Only update progress for every 1% read
-	updateEvery := int(0.01 * float64(r.readTotal))
-	if r.readProgress-r.lastUpdate > updateEvery || r.readProgress == r.readTotal {
-		fmt.Fprintf(r.output, "%d/%d (%.0f%%)\r",
-			r.readProgress,
-			r.readTotal,
-			float64(r.readProgress)/float64(r.readTotal)*100)
+	updateEvery := 4096
+	if r.readTotal > 0 {
+		// Only update progress for every 1% read
+		if increment := int(0.01 * float64(r.readTotal)); increment > updateEvery {
+			updateEvery = increment
+		}
+	}
+	if r.readProgress-r.lastUpdate > updateEvery || err != nil {
+		if r.readTotal > 0 {
+			fmt.Fprintf(r.output, r.template+"\r", r.readProgress, r.readTotal, fmt.Sprintf("%.0f%%", float64(r.readProgress)/float64(r.readTotal)*100))
+		} else {
+			fmt.Fprintf(r.output, r.template+"\r", r.readProgress, "?", "n/a")
+		}
 		r.lastUpdate = r.readProgress
 	}
 	// Send newline when complete
-	if err == io.EOF {
+	if err != nil {
 		fmt.Fprintf(r.output, "\n")
 	}
 
@@ -97,8 +104,11 @@ func (r *progressReader) Read(p []byte) (n int, err error) {
 func (r *progressReader) Close() error {
 	return io.ReadCloser(r.reader).Close()
 }
-func ProgressReader(r io.ReadCloser, size int, output io.Writer) *progressReader {
-	return &progressReader{r, output, size, 0, 0}
+func ProgressReader(r io.ReadCloser, size int, output io.Writer, template string) *progressReader {
+	if template == "" {
+		template = "%v/%v (%v)"
+	}
+	return &progressReader{r, output, size, 0, 0, template}
 }
 
 // HumanDuration returns a human-readable approximation of a duration
@@ -395,6 +405,7 @@ type KernelVersionInfo struct {
 	Specific int
 }
 
+// FIXME: this doens't build on Darwin
 func GetKernelVersion() (*KernelVersionInfo, error) {
 	var uts syscall.Utsname