func CommandAsm(c *cli.Context) {
if len(c.Args()) > 0 {
logrus.Warnf("%d additional arguments passed are ignored", len(c.Args()))
}
if len(c.String("input")) == 0 {
logrus.Fatalf("--input filename must be set")
}
if len(c.String("output")) == 0 {
logrus.Fatalf("--output filename must be set ([FILENAME|-])")
}
if len(c.String("path")) == 0 {
logrus.Fatalf("--path must be set")
}
var outputStream io.Writer
if c.String("output") == "-" {
outputStream = os.Stdout
} else {
fh, err := os.Create(c.String("output"))
if err != nil {
logrus.Fatal(err)
}
defer fh.Close()
outputStream = fh
}
// Get the tar metadata reader
mf, err := os.Open(c.String("input"))
if err != nil {
logrus.Fatal(err)
}
defer mf.Close()
mfz, err := gzip.NewReader(mf)
if err != nil {
logrus.Fatal(err)
}
defer mfz.Close()
metaUnpacker := storage.NewJSONUnpacker(mfz)
// XXX maybe get the absolute path here
fileGetter := storage.NewPathFileGetter(c.String("path"))
ots := asm.NewOutputTarStream(fileGetter, metaUnpacker)
defer ots.Close()
i, err := io.Copy(outputStream, ots)
if err != nil {
logrus.Fatal(err)
}
logrus.Infof("created %s from %s and %s (wrote %d bytes)", c.String("output"), c.String("path"), c.String("input"), i)
}
func (graph *Graph) assembleTarLayer(img *image.Image) (io.ReadCloser, error) {
root := graph.imageRoot(img.ID)
mFileName := filepath.Join(root, tarDataFileName)
mf, err := os.Open(mFileName)
if err != nil {
if !os.IsNotExist(err) {
logrus.Errorf("failed to open %q: %s", mFileName, err)
}
return nil, err
}
pR, pW := io.Pipe()
// this will need to be in a goroutine, as we are returning the stream of a
// tar archive, but can not close the metadata reader early (when this
// function returns)...
go func() {
defer mf.Close()
// let's reassemble!
logrus.Debugf("[graph] TarLayer with reassembly: %s", img.ID)
mfz, err := gzip.NewReader(mf)
if err != nil {
pW.CloseWithError(fmt.Errorf("[graph] error with %s: %s", mFileName, err))
return
}
defer mfz.Close()
// get our relative path to the container
fsLayer, err := graph.driver.Get(img.ID, "")
if err != nil {
pW.CloseWithError(err)
return
}
defer graph.driver.Put(img.ID)
metaUnpacker := storage.NewJSONUnpacker(mfz)
fileGetter := storage.NewPathFileGetter(fsLayer)
logrus.Debugf("[graph] %s is at %q", img.ID, fsLayer)
ots := asm.NewOutputTarStream(fileGetter, metaUnpacker)
defer ots.Close()
if _, err := io.Copy(pW, ots); err != nil {
pW.CloseWithError(err)
return
}
pW.Close()
}()
return pR, nil
}
func (ls *layerStore) assembleTar(graphID string, metadata io.ReadCloser, size *int64) (io.ReadCloser, error) {
type diffPathDriver interface {
DiffPath(string) (string, func() error, error)
}
diffDriver, ok := ls.driver.(diffPathDriver)
if !ok {
diffDriver = &naiveDiffPathDriver{ls.driver}
}
// get our relative path to the container
fsPath, releasePath, err := diffDriver.DiffPath(graphID)
if err != nil {
metadata.Close()
return nil, err
}
pR, pW := io.Pipe()
// this will need to be in a goroutine, as we are returning the stream of a
// tar archive, but can not close the metadata reader early (when this
// function returns)...
go func() {
defer releasePath()
defer metadata.Close()
metaUnpacker := storage.NewJSONUnpacker(metadata)
upackerCounter := &unpackSizeCounter{metaUnpacker, size}
fileGetter := storage.NewPathFileGetter(fsPath)
logrus.Debugf("Assembling tar data for %s from %s", graphID, fsPath)
ots := asm.NewOutputTarStream(fileGetter, upackerCounter)
defer ots.Close()
if _, err := io.Copy(pW, ots); err != nil {
pW.CloseWithError(err)
return
}
pW.Close()
}()
return pR, nil
}