// smartFetch the things that blobs point to, not just blobs.
func smartFetch(cl *client.Client, targ string, br *blobref.BlobRef) error {
if *flagVerbose {
log.Printf("Fetching %v into %q", br, targ)
}
rc, err := fetch(cl, br)
if err != nil {
return err
}
defer rc.Close()
sniffer := new(index.BlobSniffer)
_, err = io.CopyN(sniffer, rc, sniffSize)
if err != nil && err != io.EOF {
return err
}
sniffer.Parse()
sc, ok := sniffer.Superset()
if !ok {
// opaque data - put it in a file
f, err := os.Create(targ)
if err != nil {
return fmt.Errorf("opaque: %v", err)
}
defer f.Close()
body, _ := sniffer.Body()
r := io.MultiReader(bytes.NewBuffer(body), rc)
_, err = io.Copy(f, r)
return err
}
sc.BlobRef = br
switch sc.Type {
case "directory":
dir := filepath.Join(targ, sc.FileName)
if err := os.MkdirAll(dir, sc.FileMode()); err != nil {
return err
}
if err := setFileMeta(dir, sc); err != nil {
log.Print(err)
}
entries := blobref.Parse(sc.Entries)
if entries == nil {
return fmt.Errorf("bad entries blobref: %v", sc.Entries)
}
return smartFetch(cl, dir, entries)
case "static-set":
// directory entries
for _, m := range sc.Members {
dref := blobref.Parse(m)
if dref == nil {
return fmt.Errorf("bad member blobref: %v", m)
}
if err := smartFetch(cl, targ, dref); err != nil {
return err
}
}
return nil
case "file":
name := filepath.Join(targ, sc.FileName)
f, err := os.Create(name)
if err != nil {
return fmt.Errorf("file type: %v", err)
}
defer f.Close()
seekFetcher := blobref.SeekerFromStreamingFetcher(cl)
fr, err := schema.NewFileReader(seekFetcher, br)
if err != nil {
return fmt.Errorf("NewFileReader: %v", err)
}
defer fr.Close()
if err := setFileMeta(name, sc); err != nil {
log.Print(err)
}
return nil
default:
return errors.New("unknown blob type: " + sc.Type)
}
panic("unreachable")
}
// smartFetch the things that blobs point to, not just blobs.
func smartFetch(src blobref.StreamingFetcher, targ string, br *blobref.BlobRef) error {
rc, err := fetch(src, br)
if err != nil {
return err
}
defer rc.Close()
sniffer := new(index.BlobSniffer)
_, err = io.CopyN(sniffer, rc, sniffSize)
if err != nil && err != io.EOF {
return err
}
sniffer.Parse()
sc, ok := sniffer.Superset()
if !ok {
if *flagVerbose {
log.Printf("Fetching opaque data %v into %q", br, targ)
}
// opaque data - put it in a file
f, err := os.Create(targ)
if err != nil {
return fmt.Errorf("opaque: %v", err)
}
defer f.Close()
body, _ := sniffer.Body()
r := io.MultiReader(bytes.NewReader(body), rc)
_, err = io.Copy(f, r)
return err
}
sc.BlobRef = br
switch sc.Type {
case "directory":
dir := filepath.Join(targ, sc.FileName)
if *flagVerbose {
log.Printf("Fetching directory %v into %s", br, dir)
}
if err := os.MkdirAll(dir, sc.FileMode()); err != nil {
return err
}
if err := setFileMeta(dir, sc); err != nil {
log.Print(err)
}
entries := blobref.Parse(sc.Entries)
if entries == nil {
return fmt.Errorf("bad entries blobref: %v", sc.Entries)
}
return smartFetch(src, dir, entries)
case "static-set":
if *flagVerbose {
log.Printf("Fetching directory entries %v into %s", br, targ)
}
// directory entries
const numWorkers = 10
type work struct {
br *blobref.BlobRef
errc chan<- error
}
workc := make(chan work, len(sc.Members))
defer close(workc)
for i := 0; i < numWorkers; i++ {
go func() {
for wi := range workc {
wi.errc <- smartFetch(src, targ, wi.br)
}
}()
}
var errcs []<-chan error
for _, m := range sc.Members {
dref := blobref.Parse(m)
if dref == nil {
return fmt.Errorf("bad member blobref: %v", m)
}
errc := make(chan error, 1)
errcs = append(errcs, errc)
workc <- work{dref, errc}
}
for _, errc := range errcs {
if err := <-errc; err != nil {
return err
}
}
return nil
case "file":
seekFetcher := blobref.SeekerFromStreamingFetcher(src)
fr, err := schema.NewFileReader(seekFetcher, br)
if err != nil {
return fmt.Errorf("NewFileReader: %v", err)
}
fr.LoadAllChunks()
defer fr.Close()
name := filepath.Join(targ, sc.FileName)
if fi, err := os.Stat(name); err == nil && fi.Size() == fi.Size() {
if *flagVerbose {
log.Printf("Skipping %s; already exists.", name)
return nil
}
}
if *flagVerbose {
log.Printf("Writing %s to %s ...", br, name)
}
f, err := os.Create(name)
if err != nil {
return fmt.Errorf("file type: %v", err)
}
defer f.Close()
if _, err := io.Copy(f, fr); err != nil {
return fmt.Errorf("Copying %s to %s: %v", br, name, err)
}
if err := setFileMeta(name, sc); err != nil {
log.Print(err)
}
return nil
default:
return errors.New("unknown blob type: " + sc.Type)
}
panic("unreachable")
}