Use a build flag to disable resumable digests.

Signed-off-by: Andy Goldstein <agoldste@redhat.com>
This commit is contained in:
Andy Goldstein 2015-04-16 01:12:45 +00:00
parent 9898552656
commit 480d864fc4
4 changed files with 65 additions and 19 deletions

View file

@ -138,13 +138,16 @@ func (ls *layerStore) newLayerUpload(uuid, path string, startedAt time.Time) (di
return nil, err
}
return &layerWriter{
lw := &layerWriter{
layerStore: ls,
uuid: uuid,
startedAt: startedAt,
resumableDigester: digest.NewCanonicalResumableDigester(),
bufferedFileWriter: *fw,
}, nil
}
lw.setupResumableDigester()
return lw, nil
}
func (ls *layerStore) path(dgst digest.Digest) (string, error) {

View file

@ -87,6 +87,10 @@ func (lw *layerWriter) Cancel() error {
}
func (lw *layerWriter) Write(p []byte) (int, error) {
if lw.resumableDigester == nil {
return lw.bufferedFileWriter.Write(p)
}
// Ensure that the current write offset matches how many bytes have been
// written to the digester. If not, we need to update the digest state to
// match the current write position.
@ -98,6 +102,10 @@ func (lw *layerWriter) Write(p []byte) (int, error) {
}
func (lw *layerWriter) ReadFrom(r io.Reader) (n int64, err error) {
if lw.resumableDigester == nil {
return lw.bufferedFileWriter.ReadFrom(r)
}
// Ensure that the current write offset matches how many bytes have been
// written to the digester. If not, we need to update the digest state to
// match the current write position.
@ -113,8 +121,10 @@ func (lw *layerWriter) Close() error {
return lw.err
}
if err := lw.storeHashState(); err != nil {
return err
if lw.resumableDigester != nil {
if err := lw.storeHashState(); err != nil {
return err
}
}
return lw.bufferedFileWriter.Close()
@ -261,22 +271,37 @@ func (lw *layerWriter) storeHashState() error {
// validateLayer checks the layer data against the digest, returning an error
// if it does not match. The canonical digest is returned.
func (lw *layerWriter) validateLayer(dgst digest.Digest) (digest.Digest, error) {
// Restore the hasher state to the end of the upload.
if err := lw.resumeHashAt(lw.size); err != nil {
return "", err
var (
verified, fullHash bool
canonical digest.Digest
)
if lw.resumableDigester != nil {
// Restore the hasher state to the end of the upload.
if err := lw.resumeHashAt(lw.size); err != nil {
return "", err
}
canonical = lw.resumableDigester.Digest()
if canonical.Algorithm() == dgst.Algorithm() {
// Common case: client and server prefer the same canonical digest
// algorithm - currently SHA256.
verified = dgst == canonical
} else {
// The client wants to use a different digest algorithm. They'll just
// have to be patient and wait for us to download and re-hash the
// uploaded content using that digest algorithm.
fullHash = true
}
} else {
// Not using resumable digests, so we need to hash the entire layer.
fullHash = true
}
var verified bool
canonical := lw.resumableDigester.Digest()
if fullHash {
digester := digest.NewCanonicalDigester()
if canonical.Algorithm() == dgst.Algorithm() {
// Common case: client and server prefer the same canonical digest
// algorithm - currently SHA256.
verified = dgst == canonical
} else {
// The client wants to use a different digest algorithm. They'll just
// have to be patient and wait for us to download and re-hash the
// uploaded content using that digest algorithm.
digestVerifier, err := digest.NewDigestVerifier(dgst)
if err != nil {
return "", err
@ -288,10 +313,13 @@ func (lw *layerWriter) validateLayer(dgst digest.Digest) (digest.Digest, error)
return "", err
}
if _, err = io.Copy(digestVerifier, fr); err != nil {
tr := io.TeeReader(fr, digester)
if _, err = io.Copy(digestVerifier, tr); err != nil {
return "", err
}
canonical = digester.Digest()
verified = digestVerifier.Verified()
}

View file

@ -0,0 +1,6 @@
// +build noresumabledigest
package storage
func (lw *layerWriter) setupResumableDigester() {
}

View file

@ -0,0 +1,9 @@
// +build !noresumabledigest
package storage
import "github.com/docker/distribution/digest"
func (lw *layerWriter) setupResumableDigester() {
lw.resumableDigester = digest.NewCanonicalResumableDigester()
}