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, 35 insertions, 31 deletions

diff --git a/common_test.go b/common_test.go
index 95282ea..fed5301 100644
--- a/common_test.go
+++ b/common_test.go
@@ -1,17 +1,17 @@
 package git
 
 import (
-	"errors"
+	"fmt"
 	"io"
 	"os"
 	"testing"
 
 	"gopkg.in/src-d/go-git.v4/fixtures"
 	"gopkg.in/src-d/go-git.v4/plumbing"
-	"gopkg.in/src-d/go-git.v4/plumbing/client"
-	"gopkg.in/src-d/go-git.v4/plumbing/client/common"
 	"gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
 	"gopkg.in/src-d/go-git.v4/plumbing/format/packp"
+	"gopkg.in/src-d/go-git.v4/plumbing/transport"
+	"gopkg.in/src-d/go-git.v4/plumbing/transport/client"
 	"gopkg.in/src-d/go-git.v4/storage/filesystem"
 
 	. "gopkg.in/check.v1"
@@ -36,9 +36,7 @@ func (s *BaseSuite) SetUpSuite(c *C) {
 }
 
 func (s *BaseSuite) installMockProtocol(c *C) {
-	clients.InstallProtocol("https", func(end common.Endpoint) common.GitUploadPackService {
-		return &MockGitUploadPackService{endpoint: end}
-	})
+	client.InstallProtocol("https", &MockClient{})
 }
 
 func (s *BaseSuite) buildRepository(c *C) {
@@ -68,38 +66,47 @@ func (s *BaseSuite) buildRepositories(c *C, f fixtures.Fixtures) {
 
 const RepositoryFixture = "https://github.com/git-fixtures/basic.git"
 
-type MockGitUploadPackService struct {
-	connected bool
-	endpoint  common.Endpoint
-	auth      common.AuthMethod
+type MockClient struct{}
+
+type MockFetchPackSession struct {
+	endpoint transport.Endpoint
+	auth     transport.AuthMethod
 }
 
-func (p *MockGitUploadPackService) Connect() error {
-	p.connected = true
-	return nil
+func (c *MockClient) NewFetchPackSession(ep transport.Endpoint) (
+	transport.FetchPackSession, error) {
+
+	return &MockFetchPackSession{
+		endpoint: ep,
+		auth:     nil,
+	}, nil
 }
 
-func (p *MockGitUploadPackService) SetAuth(auth common.AuthMethod) error {
-	p.auth = auth
+func (c *MockClient) NewSendPackSession(ep transport.Endpoint) (
+	transport.SendPackSession, error) {
+
+	return nil, fmt.Errorf("not supported")
+}
+
+func (c *MockFetchPackSession) SetAuth(auth transport.AuthMethod) error {
+	c.auth = auth
 	return nil
 }
 
-func (p *MockGitUploadPackService) Info() (*common.GitUploadPackInfo, error) {
-	if !p.connected {
-		return nil, errors.New("not connected")
-	}
+func (c *MockFetchPackSession) AdvertisedReferences() (
+	*transport.UploadPackInfo, error) {
 
-	h := fixtures.ByURL(p.endpoint.String()).One().Head
+	h := fixtures.ByURL(c.endpoint.String()).One().Head
 
-	c := packp.NewCapabilities()
-	c.Decode("6ecf0ef2c2dffb796033e5a02219af86ec6584e5 HEADmulti_ack thin-pack side-band side-band-64k ofs-delta shallow no-progress include-tag multi_ack_detailed no-done symref=HEAD:refs/heads/master agent=git/2:2.4.8~dbussink-fix-enterprise-tokens-compilation-1167-gc7006cf")
+	cap := packp.NewCapabilities()
+	cap.Decode("6ecf0ef2c2dffb796033e5a02219af86ec6584e5 HEADmulti_ack thin-pack side-band side-band-64k ofs-delta shallow no-progress include-tag multi_ack_detailed no-done symref=HEAD:refs/heads/master agent=git/2:2.4.8~dbussink-fix-enterprise-tokens-compilation-1167-gc7006cf")
 
 	ref := plumbing.ReferenceName("refs/heads/master")
 	branch := plumbing.ReferenceName("refs/heads/branch")
 	tag := plumbing.ReferenceName("refs/tags/v1.0.0")
 
-	return &common.GitUploadPackInfo{
-		Capabilities: c,
+	return &transport.UploadPackInfo{
+		Capabilities: cap,
 		Refs: map[plumbing.ReferenceName]*plumbing.Reference{
 			plumbing.HEAD: plumbing.NewSymbolicReference(plumbing.HEAD, ref),
 			ref:           plumbing.NewHashReference(ref, h),
@@ -109,12 +116,10 @@ func (p *MockGitUploadPackService) Info() (*common.GitUploadPackInfo, error) {
 	}, nil
 }
 
-func (p *MockGitUploadPackService) Fetch(r *common.GitUploadPackRequest) (io.ReadCloser, error) {
-	if !p.connected {
-		return nil, errors.New("not connected")
-	}
+func (c *MockFetchPackSession) FetchPack(
+	r *transport.UploadPackRequest) (io.ReadCloser, error) {
 
-	f := fixtures.ByURL(p.endpoint.String())
+	f := fixtures.ByURL(c.endpoint.String())
 
 	if len(r.Wants) == 1 {
 		return f.Exclude("single-branch").One().Packfile(), nil
@@ -123,8 +128,7 @@ func (p *MockGitUploadPackService) Fetch(r *common.GitUploadPackRequest) (io.Rea
 	return f.One().Packfile(), nil
 }
 
-func (p *MockGitUploadPackService) Disconnect() error {
-	p.connected = false
+func (c *MockFetchPackSession) Close() error {
 	return nil
 }