server: add git server implementation (#190)

* server: add generic server implementation (transport-independent),
  both for git-upload-pack and git-receive-pack.
* server: move internal functions to internal/common.
* cli: add git-receive-pack and git-upload-pack implementations.
* format/packfile: add UpdateObjectStorage function, extracted from
  Remote.
* transport: implement tranport RPC-like, only with git-upload-pack and
  git-receive-pack methods. Client renamed to Transport.
* storer: add storer.Storer interface.
* protocol/packp: add UploadPackResponse constructor with packfile.
* protocol/packp: fix UploadPackResponse encoding, add tests.
* protocol/packp/capability: implement All.

1 files changed, 11 insertions, 33 deletions

diff --git a/remote.go b/remote.go
index 102a764..e8d56fc 100644
--- a/remote.go
+++ b/remote.go
@@ -130,7 +130,7 @@ func (r *Remote) fetch(o *FetchOptions) (refs storer.ReferenceStorer, err error)
 		o.RefSpecs = r.c.Fetch
 	}
 
-	s, err := newFetchPackSession(r.c.URL)
+	s, err := newUploadPackSession(r.c.URL)
 	if err != nil {
 		return nil, err
 	}
@@ -173,25 +173,25 @@ func (r *Remote) fetch(o *FetchOptions) (refs storer.ReferenceStorer, err error)
 	return remoteRefs, err
 }
 
-func newFetchPackSession(url string) (transport.FetchPackSession, error) {
+func newUploadPackSession(url string) (transport.UploadPackSession, error) {
 	c, ep, err := newClient(url)
 	if err != nil {
 		return nil, err
 	}
 
-	return c.NewFetchPackSession(ep)
+	return c.NewUploadPackSession(ep)
 }
 
-func newSendPackSession(url string) (transport.SendPackSession, error) {
+func newSendPackSession(url string) (transport.ReceivePackSession, error) {
 	c, ep, err := newClient(url)
 	if err != nil {
 		return nil, err
 	}
 
-	return c.NewSendPackSession(ep)
+	return c.NewReceivePackSession(ep)
 }
 
-func newClient(url string) (transport.Client, transport.Endpoint, error) {
+func newClient(url string) (transport.Transport, transport.Endpoint, error) {
 	ep, err := transport.NewEndpoint(url)
 	if err != nil {
 		return nil, transport.Endpoint{}, err
@@ -205,10 +205,10 @@ func newClient(url string) (transport.Client, transport.Endpoint, error) {
 	return c, ep, err
 }
 
-func (r *Remote) fetchPack(o *FetchOptions, s transport.FetchPackSession,
+func (r *Remote) fetchPack(o *FetchOptions, s transport.UploadPackSession,
 	req *packp.UploadPackRequest) (err error) {
 
-	reader, err := s.FetchPack(req)
+	reader, err := s.UploadPack(req)
 	if err != nil {
 		return err
 	}
@@ -219,7 +219,7 @@ func (r *Remote) fetchPack(o *FetchOptions, s transport.FetchPackSession,
 		return err
 	}
 
-	if err = r.updateObjectStorage(
+	if err = packfile.UpdateObjectStorage(r.s,
 		buildSidebandIfSupported(req.Capabilities, reader, r.p),
 	); err != nil {
 		return err
@@ -406,28 +406,6 @@ func (r *Remote) newUploadPackRequest(o *FetchOptions,
 	return req, nil
 }
 
-func (r *Remote) updateObjectStorage(reader io.Reader) error {
-	if sw, ok := r.s.(storer.PackfileWriter); ok {
-		w, err := sw.PackfileWriter()
-		if err != nil {
-			return err
-		}
-
-		defer w.Close()
-		_, err = io.Copy(w, reader)
-		return err
-	}
-
-	stream := packfile.NewScanner(reader)
-	d, err := packfile.NewDecoder(stream, r.s)
-	if err != nil {
-		return err
-	}
-
-	_, err = d.Decode()
-	return err
-}
-
 func buildSidebandIfSupported(l *capability.List, reader io.Reader, p sideband.Progress) io.Reader {
 	var t sideband.Type
 
@@ -532,7 +510,7 @@ func referencesToHashes(refs storer.ReferenceStorer) ([]plumbing.Hash, error) {
 	return hs, nil
 }
 
-func pushHashes(sess transport.SendPackSession, sto storer.EncodedObjectStorer,
+func pushHashes(sess transport.ReceivePackSession, sto storer.EncodedObjectStorer,
 	req *packp.ReferenceUpdateRequest, hs []plumbing.Hash) (*packp.ReportStatus, error) {
 
 	rd, wr := io.Pipe()
@@ -548,7 +526,7 @@ func pushHashes(sess transport.SendPackSession, sto storer.EncodedObjectStorer,
 		done <- wr.Close()
 	}()
 
-	rs, err := sess.SendPack(req)
+	rs, err := sess.ReceivePack(req)
 	if err != nil {
 		return nil, err
 	}