transport: create Client interface (#132)

* plumbing: move plumbing/client package to plumbing/transport.

* transport: create Client interface.

* A Client can instantiate any client transport service.
* InstallProtocol installs a Client for a given protocol,
  instead of just a UploadPackService.
* A Client can open a session for fetch-pack or send-pack
  for a specific Endpoint.
* Adapt ssh and http clients to the new client interface.

* updated doc

1 files changed, 96 insertions, 0 deletions

diff --git a/plumbing/transport/fetch_pack_test.go b/plumbing/transport/fetch_pack_test.go
new file mode 100644
index 0000000..7a7f86f
--- /dev/null
+++ b/plumbing/transport/fetch_pack_test.go
@@ -0,0 +1,96 @@
+package transport
+
+import (
+	"bytes"
+	"encoding/base64"
+
+	"gopkg.in/src-d/go-git.v4/plumbing"
+
+	. "gopkg.in/check.v1"
+)
+
+type UploadPackSuite struct{}
+
+var _ = Suite(&UploadPackSuite{})
+
+const UploadPackInfoFixture = "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"
+
+func (s *UploadPackSuite) TestUploadPackInfo(c *C) {
+	b, _ := base64.StdEncoding.DecodeString(UploadPackInfoFixture)
+
+	i := NewUploadPackInfo()
+	err := i.Decode(bytes.NewBuffer(b))
+	c.Assert(err, IsNil)
+
+	name := i.Capabilities.SymbolicReference("HEAD")
+	c.Assert(name, Equals, "refs/heads/master")
+	c.Assert(i.Refs, HasLen, 4)
+
+	ref := i.Refs[plumbing.ReferenceName(name)]
+	c.Assert(ref, NotNil)
+	c.Assert(ref.Hash().String(), Equals, "6ecf0ef2c2dffb796033e5a02219af86ec6584e5")
+
+	ref = i.Refs[plumbing.HEAD]
+	c.Assert(ref, NotNil)
+	c.Assert(ref.Target(), Equals, plumbing.ReferenceName(name))
+}
+
+const UploadPackInfoNoHEADFixture = "MDAxZSMgc2VydmljZT1naXQtdXBsb2FkLXBhY2sKMDAwMDAwYmNkN2UxZmVlMjYxMjM0YmIzYTQzYzA5NmY1NTg3NDhhNTY5ZDc5ZWZmIHJlZnMvaGVhZHMvdjQAbXVsdGlfYWNrIHRoaW4tcGFjayBzaWRlLWJhbmQgc2lkZS1iYW5kLTY0ayBvZnMtZGVsdGEgc2hhbGxvdyBuby1wcm9ncmVzcyBpbmNsdWRlLXRhZyBtdWx0aV9hY2tfZGV0YWlsZWQgbm8tZG9uZSBhZ2VudD1naXQvMS45LjEKMDAwMA=="
+
+func (s *UploadPackSuite) TestUploadPackInfoNoHEAD(c *C) {
+	b, _ := base64.StdEncoding.DecodeString(UploadPackInfoNoHEADFixture)
+
+	i := NewUploadPackInfo()
+	err := i.Decode(bytes.NewBuffer(b))
+	c.Assert(err, IsNil)
+
+	name := i.Capabilities.SymbolicReference("HEAD")
+	c.Assert(name, Equals, "")
+	c.Assert(i.Refs, HasLen, 1)
+
+	ref := i.Refs["refs/heads/v4"]
+	c.Assert(ref, NotNil)
+	c.Assert(ref.Hash().String(), Equals, "d7e1fee261234bb3a43c096f558748a569d79eff")
+}
+
+func (s *UploadPackSuite) TestUploadPackInfoEmpty(c *C) {
+	b := bytes.NewBuffer(nil)
+
+	i := NewUploadPackInfo()
+	err := i.Decode(b)
+	c.Assert(err, ErrorMatches, "permanent.*empty.*")
+}
+
+func (s *UploadPackSuite) TestUploadPackEncode(c *C) {
+	info := NewUploadPackInfo()
+	info.Capabilities.Add("symref", "HEAD:refs/heads/master")
+
+	ref := plumbing.ReferenceName("refs/heads/master")
+	hash := plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5")
+	info.Refs = map[plumbing.ReferenceName]*plumbing.Reference{
+		plumbing.HEAD: plumbing.NewSymbolicReference(plumbing.HEAD, ref),
+		ref:           plumbing.NewHashReference(ref, hash),
+	}
+
+	c.Assert(info.Head(), NotNil)
+	c.Assert(info.String(), Equals,
+		"001e# service=git-upload-pack\n"+
+			"000000506ecf0ef2c2dffb796033e5a02219af86ec6584e5 HEAD\x00symref=HEAD:refs/heads/master\n"+
+			"003f6ecf0ef2c2dffb796033e5a02219af86ec6584e5 refs/heads/master\n"+
+			"0000",
+	)
+}
+
+func (s *UploadPackSuite) TestUploadPackRequest(c *C) {
+	r := &UploadPackRequest{}
+	r.Want(plumbing.NewHash("d82f291cde9987322c8a0c81a325e1ba6159684c"))
+	r.Want(plumbing.NewHash("2b41ef280fdb67a9b250678686a0c3e03b0a9989"))
+	r.Have(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+
+	c.Assert(r.String(), Equals,
+		"0032want d82f291cde9987322c8a0c81a325e1ba6159684c\n"+
+			"0032want 2b41ef280fdb67a9b250678686a0c3e03b0a9989\n"+
+			"0032have 6ecf0ef2c2dffb796033e5a02219af86ec6584e5\n0000"+
+			"0009done\n",
+	)
+}