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, 105 insertions, 0 deletions

diff --git a/plumbing/transport/file/server_test.go b/plumbing/transport/file/server_test.go
new file mode 100644
index 0000000..ff462e2
--- /dev/null
+++ b/plumbing/transport/file/server_test.go
@@ -0,0 +1,105 @@
+package file
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+
+	"gopkg.in/src-d/go-git.v4/fixtures"
+
+	. "gopkg.in/check.v1"
+)
+
+type ServerSuite struct {
+	CommonSuite
+	RemoteName string
+	SrcPath    string
+	DstPath    string
+	DstURL     string
+}
+
+var _ = Suite(&ServerSuite{})
+
+func (s *ServerSuite) SetUpSuite(c *C) {
+	s.CommonSuite.SetUpSuite(c)
+
+	s.RemoteName = "test"
+
+	fixture := fixtures.Basic().One()
+	s.SrcPath = fixture.DotGit().Base()
+
+	fixture = fixtures.ByTag("empty").One()
+	s.DstPath = fixture.DotGit().Base()
+	s.DstURL = fmt.Sprintf("file://%s", s.DstPath)
+
+	cmd := exec.Command("git", "remote", "add", s.RemoteName, s.DstURL)
+	cmd.Dir = s.SrcPath
+	c.Assert(cmd.Run(), IsNil)
+}
+
+func (s *ServerSuite) TestPush(c *C) {
+	// git <2.0 cannot push to an empty repository without a refspec.
+	cmd := exec.Command("git", "push",
+		"--receive-pack", s.ReceivePackBin,
+		s.RemoteName, "refs/heads/*:refs/heads/*",
+	)
+	cmd.Dir = s.SrcPath
+	cmd.Env = os.Environ()
+	cmd.Env = append(cmd.Env, "GIT_TRACE=true", "GIT_TRACE_PACKET=true")
+	stdout, stderr, err := execAndGetOutput(c, cmd)
+	c.Assert(err, IsNil, Commentf("STDOUT:\n%s\nSTDERR:\n%s\n", stdout, stderr))
+}
+
+func (s *ServerSuite) TestClone(c *C) {
+	pathToClone := c.MkDir()
+
+	cmd := exec.Command("git", "clone",
+		"--upload-pack", s.UploadPackBin,
+		s.SrcPath, pathToClone,
+	)
+	cmd.Env = os.Environ()
+	cmd.Env = append(cmd.Env, "GIT_TRACE=true", "GIT_TRACE_PACKET=true")
+	stdout, stderr, err := execAndGetOutput(c, cmd)
+	c.Assert(err, IsNil, Commentf("STDOUT:\n%s\nSTDERR:\n%s\n", stdout, stderr))
+}
+
+func execAndGetOutput(c *C, cmd *exec.Cmd) (stdout, stderr string, err error) {
+	sout, err := cmd.StdoutPipe()
+	c.Assert(err, IsNil)
+	serr, err := cmd.StderrPipe()
+	c.Assert(err, IsNil)
+
+	outChan, outErr := readAllAsync(sout)
+	errChan, errErr := readAllAsync(serr)
+
+	c.Assert(cmd.Start(), IsNil)
+
+	if err = cmd.Wait(); err != nil {
+		return <-outChan, <-errChan, err
+	}
+
+	if err := <-outErr; err != nil {
+		return <-outChan, <-errChan, err
+	}
+
+	return <-outChan, <-errChan, <-errErr
+}
+
+func readAllAsync(r io.Reader) (out chan string, err chan error) {
+	out = make(chan string, 1)
+	err = make(chan error, 1)
+	go func() {
+		b, e := ioutil.ReadAll(r)
+		if e != nil {
+			err <- e
+		} else {
+			err <- nil
+		}
+
+		out <- string(b)
+	}()
+
+	return out, err
+}