clients and remote: fetch implementation

9 files changed, 145 insertions, 194 deletions

diff --git a/client.go b/client.go
deleted file mode 100644
index 8855989..0000000
--- a/client.go
+++ /dev/null
@@ -1,181 +0,0 @@
-package git
-
-import (
-	"fmt"
-	"io"
-	"net/http"
-	"net/url"
-	"strings"
-
-	"gopkg.in/src-d/go-git.v2/pktline"
-
-	"github.com/sourcegraph/go-vcsurl"
-)
-
-type Client struct {
-	url    string
-	client *http.Client
-}
-
-func NewClient(url string) *Client {
-	vcs, _ := vcsurl.Parse(url)
-
-	return &Client{url: vcs.Link(), client: &http.Client{}}
-}
-
-func (c *Client) Refs() (*Refs, error) {
-	req, _ := c.buildRequest(
-		"GET",
-		fmt.Sprintf("%s/info/refs?service=git-upload-pack", c.url),
-		nil,
-	)
-
-	res, err := c.client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-
-	if res.StatusCode >= 400 {
-		return nil, &ErrNotFound{c.url}
-	}
-
-	defer res.Body.Close()
-	d := pktline.NewDecoder(res.Body)
-
-	content, err := d.ReadAll()
-	if err != nil {
-		return nil, err
-	}
-
-	return c.buildRefsFromContent(content), nil
-}
-
-func (c *Client) buildRefsFromContent(content []string) *Refs {
-	refs := &Refs{branches: make(map[string]string, 0)}
-	for _, line := range content {
-		if line[0] == '#' {
-			continue
-		}
-
-		if refs.defaultBranch == "" {
-			refs.defaultBranch = c.getDefaultBranchFromLine(line)
-		} else {
-			commit, branch := c.getCommitAndBranch(line)
-			refs.branches[branch] = commit
-		}
-	}
-
-	return refs
-}
-
-func (c *Client) getDefaultBranchFromLine(line string) string {
-	args, _ := url.ParseQuery(strings.Replace(line, " ", "&", -1))
-
-	link, ok := args["symref"]
-	if !ok {
-		return ""
-	}
-
-	parts := strings.Split(link[0], ":")
-	if len(parts) != 2 || parts[0] != "HEAD" {
-		return ""
-	}
-
-	return parts[1]
-}
-
-func (c *Client) getCommitAndBranch(line string) (string, string) {
-	parts := strings.Split(strings.Trim(line, " \n"), " ")
-	if len(parts) != 2 {
-		return "", ""
-	}
-
-	return parts[0], parts[1]
-}
-
-func (c *Client) PackFile(want string) (io.ReadCloser, error) {
-	e := pktline.NewEncoder()
-	e.AddLine(fmt.Sprintf("want %s", want))
-	e.AddFlush()
-	e.AddLine("done")
-
-	req, err := c.buildRequest(
-		"POST",
-		fmt.Sprintf("%s/git-upload-pack", c.url),
-		e.GetReader(),
-	)
-	if err != nil {
-		return nil, err
-	}
-
-	res, err := c.client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-
-	h := make([]byte, 8)
-	if _, err := res.Body.Read(h); err != nil {
-		return nil, err
-	}
-
-	return res.Body, nil
-}
-
-func (c *Client) buildRequest(method, url string, content *strings.Reader) (*http.Request, error) {
-	var req *http.Request
-	var err error
-	if content == nil {
-		req, err = http.NewRequest(method, url, nil)
-	} else {
-		req, err = http.NewRequest(method, url, content)
-	}
-
-	if err != nil {
-		return nil, err
-	}
-
-	c.applyHeadersToRequest(req, content)
-	return req, nil
-}
-
-func (c *Client) applyHeadersToRequest(req *http.Request, content *strings.Reader) {
-	req.Header.Add("User-Agent", "git/1.0")
-	req.Header.Add("Host", "github.com")
-
-	if content == nil {
-		req.Header.Add("Accept", "*/*")
-	} else {
-		req.Header.Add("Accept", "application/x-git-upload-pack-result")
-		req.Header.Add("Content-Type", "application/x-git-upload-pack-request")
-		req.Header.Add("Content-Length", string(content.Len()))
-	}
-}
-
-type Refs struct {
-	defaultBranch string
-	branches      map[string]string
-}
-
-func (r *Refs) DefaultBranch() string {
-	return r.defaultBranch
-}
-
-func (r *Refs) DefaultBranchCommit() string {
-	return r.branches[r.defaultBranch]
-}
-
-func (r *Refs) Branches() map[string]string {
-	return r.branches
-}
-
-type ErrNotFound struct {
-	url string
-}
-
-func (e *ErrNotFound) Url() string {
-	return e.url
-}
-
-func (e *ErrNotFound) Error() string {
-	return fmt.Sprintf("Unable to find %q", e.url)
-}
diff --git a/clients/common.go b/clients/common.go
index 720de86..8003d07 100644
--- a/clients/common.go
+++ b/clients/common.go
@@ -1,6 +1,8 @@
 package clients
 
 import (
+	"io"
+
 	"gopkg.in/src-d/go-git.v2/clients/common"
 	"gopkg.in/src-d/go-git.v2/clients/http"
 )
@@ -8,6 +10,7 @@ import (
 type GitUploadPackService interface {
 	Connect(url common.Endpoint) error
 	Info() (*common.GitUploadPackInfo, error)
+	Fetch(r *common.GitUploadPackRequest) (io.ReadCloser, error)
 }
 
 func NewGitUploadPackService() GitUploadPackService {
diff --git a/clients/common/common.go b/clients/common/common.go
index 3527d7c..c3d15c1 100644
--- a/clients/common/common.go
+++ b/clients/common/common.go
@@ -2,6 +2,7 @@ package common
 
 import (
 	"fmt"
+	"io/ioutil"
 	"net/url"
 	"strings"
 
@@ -72,9 +73,14 @@ func (r Capabilities) SymbolicReference(sym string) string {
 	return ""
 }
 
+type RemoteHead struct {
+	Id   string
+	Name string
+}
+
 type GitUploadPackInfo struct {
 	Capabilities Capabilities
-	Branches     map[string]string
+	Refs         map[string]*RemoteHead
 }
 
 func NewGitUploadPackInfo(d *pktline.Decoder) (*GitUploadPackInfo, error) {
@@ -92,7 +98,7 @@ func (r *GitUploadPackInfo) read(d *pktline.Decoder) error {
 		return err
 	}
 
-	r.Branches = map[string]string{}
+	r.Refs = map[string]*RemoteHead{}
 	for _, line := range lines {
 		if !r.isValidLine(line) {
 			continue
@@ -118,15 +124,41 @@ func (r *GitUploadPackInfo) isValidLine(line string) bool {
 }
 
 func (r *GitUploadPackInfo) readLine(line string) {
-	commit, branch := r.getCommitAndBranch(line)
-	r.Branches[branch] = commit
+	rh := r.getRemoteHead(line)
+	r.Refs[rh.Name] = rh
 }
 
-func (r *GitUploadPackInfo) getCommitAndBranch(line string) (string, string) {
+func (r *GitUploadPackInfo) getRemoteHead(line string) *RemoteHead {
 	parts := strings.Split(strings.Trim(line, " \n"), " ")
 	if len(parts) != 2 {
-		return "", ""
+		return nil
 	}
 
-	return parts[0], parts[1]
+	return &RemoteHead{parts[0], parts[1]}
+}
+
+type GitUploadPackRequest struct {
+	Want []string
+	Have []string
+}
+
+func (r *GitUploadPackRequest) String() string {
+	b, _ := ioutil.ReadAll(r.Reader())
+	return string(b)
+}
+
+func (r *GitUploadPackRequest) Reader() *strings.Reader {
+	e := pktline.NewEncoder()
+	for _, want := range r.Want {
+		e.AddLine(fmt.Sprintf("want %s", want))
+	}
+
+	for _, have := range r.Have {
+		e.AddLine(fmt.Sprintf("have %s", have))
+	}
+
+	e.AddFlush()
+	e.AddLine("done")
+
+	return e.GetReader()
 }
diff --git a/clients/common/common_test.go b/clients/common/common_test.go
index 0b9b60a..37d4ff9 100644
--- a/clients/common/common_test.go
+++ b/clients/common/common_test.go
@@ -1,9 +1,12 @@
 package common
 
 import (
+	"bytes"
+	"encoding/base64"
 	"testing"
 
 	. "gopkg.in/check.v1"
+	"gopkg.in/src-d/go-git.v2/pktline"
 )
 
 func Test(t *testing.T) { TestingT(t) }
@@ -35,3 +38,25 @@ func (s *SuiteCommon) TestCapabilitiesSymbolicReference(c *C) {
 	cap := parseCapabilities(CapabilitiesFixture)
 	c.Assert(cap.SymbolicReference("HEAD"), Equals, "refs/heads/master")
 }
+
+const GitUploadPackInfoFixture = "MDAxZSMgc2VydmljZT1naXQtdXBsb2FkLXBhY2sKMDAwMDAxMGM2ZWNmMGVmMmMyZGZmYjc5NjAzM2U1YTAyMjE5YWY4NmVjNjU4NGU1IEhFQUQAbXVsdGlfYWNrIHRoaW4tcGFjayBzaWRlLWJhbmQgc2lkZS1iYW5kLTY0ayBvZnMtZGVsdGEgc2hhbGxvdyBuby1wcm9ncmVzcyBpbmNsdWRlLXRhZyBtdWx0aV9hY2tfZGV0YWlsZWQgbm8tZG9uZSBzeW1yZWY9SEVBRDpyZWZzL2hlYWRzL21hc3RlciBhZ2VudD1naXQvMjoyLjQuOH5kYnVzc2luay1maXgtZW50ZXJwcmlzZS10b2tlbnMtY29tcGlsYXRpb24tMTE2Ny1nYzcwMDZjZgowMDNmZThkM2ZmYWI1NTI4OTVjMTliOWZjZjdhYTI2NGQyNzdjZGUzMzg4MSByZWZzL2hlYWRzL2JyYW5jaAowMDNmNmVjZjBlZjJjMmRmZmI3OTYwMzNlNWEwMjIxOWFmODZlYzY1ODRlNSByZWZzL2hlYWRzL21hc3RlcgowMDNlYjhlNDcxZjU4YmNiY2E2M2IwN2JkYTIwZTQyODE5MDQwOWMyZGI0NyByZWZzL3B1bGwvMS9oZWFkCjAwMDA="
+
+func (s *SuiteCommon) TestGitUploadPackInfo(c *C) {
+	b, _ := base64.StdEncoding.DecodeString(GitUploadPackInfoFixture)
+	info, err := NewGitUploadPackInfo(pktline.NewDecoder(bytes.NewBuffer(b)))
+	c.Assert(err, IsNil)
+
+	ref := info.Capabilities.SymbolicReference("HEAD")
+	c.Assert(ref, Equals, "refs/heads/master")
+	c.Assert(info.Refs[ref].Id, Equals, "6ecf0ef2c2dffb796033e5a02219af86ec6584e5")
+	c.Assert(info.Refs[ref].Name, Equals, "refs/heads/master")
+}
+
+func (s *SuiteCommon) TestGitUploadPackRequest(c *C) {
+	r := &GitUploadPackRequest{
+		Want: []string{"foo", "qux"},
+		Have: []string{"bar"},
+	}
+
+	c.Assert(r.String(), Equals, "000dwant foo\n000dwant qux\n000dhave bar\n00000009done\n")
+}
diff --git a/clients/http/git_upload_pack.go b/clients/http/git_upload_pack.go
index 96dbdce..b128c1c 100644
--- a/clients/http/git_upload_pack.go
+++ b/clients/http/git_upload_pack.go
@@ -1,6 +1,7 @@
 package http
 
 import (
+	"fmt"
 	"io"
 	"net/http"
 	"strings"
@@ -28,7 +29,8 @@ func (s *GitUploadPackService) Connect(url common.Endpoint) error {
 }
 
 func (s *GitUploadPackService) Info() (*common.GitUploadPackInfo, error) {
-	res, err := s.doRequest("GET", common.GitUploadPackServiceName, nil)
+	url := fmt.Sprintf("%s/info/refs?service=%s", s.endpoint, common.GitUploadPackServiceName)
+	res, err := s.doRequest("GET", url, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -39,13 +41,28 @@ func (s *GitUploadPackService) Info() (*common.GitUploadPackInfo, error) {
 	return common.NewGitUploadPackInfo(dec)
 }
 
-func (s *GitUploadPackService) doRequest(method, service string, content *strings.Reader) (*http.Response, error) {
+func (s *GitUploadPackService) Fetch(r *common.GitUploadPackRequest) (io.ReadCloser, error) {
+	url := fmt.Sprintf("%s/%s", s.endpoint, common.GitUploadPackServiceName)
+	res, err := s.doRequest("POST", url, r.Reader())
+	if err != nil {
+		return nil, err
+	}
+
+	h := make([]byte, 8)
+	if _, err := res.Body.Read(h); err != nil {
+		return nil, err
+	}
+
+	return res.Body, nil
+}
+
+func (s *GitUploadPackService) doRequest(method, url string, content *strings.Reader) (*http.Response, error) {
 	var body io.Reader
 	if content != nil {
 		body = content
 	}
 
-	req, err := http.NewRequest(method, s.endpoint.Service(service), body)
+	req, err := http.NewRequest(method, url, body)
 	if err != nil {
 		return nil, err
 	}
diff --git a/clients/http/git_upload_pack_test.go b/clients/http/git_upload_pack_test.go
index b478445..603cd1b 100644
--- a/clients/http/git_upload_pack_test.go
+++ b/clients/http/git_upload_pack_test.go
@@ -1,6 +1,11 @@
 package http
 
-import . "gopkg.in/check.v1"
+import (
+	"io/ioutil"
+
+	. "gopkg.in/check.v1"
+	"gopkg.in/src-d/go-git.v2/clients/common"
+)
 
 type SuiteRemote struct{}
 
@@ -30,3 +35,18 @@ func (s *SuiteRemote) TestCapabilities(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(info.Capabilities.Get("agent"), HasLen, 1)
 }
+
+func (s *SuiteRemote) TestFetch(c *C) {
+	r := NewGitUploadPackService()
+	c.Assert(r.Connect(RepositoryFixture), IsNil)
+
+	reader, err := r.Fetch(&common.GitUploadPackRequest{
+		Want: []string{"6ecf0ef2c2dffb796033e5a02219af86ec6584e5"},
+	})
+
+	c.Assert(err, IsNil)
+
+	b, err := ioutil.ReadAll(reader)
+	c.Assert(err, IsNil)
+	c.Assert(b, HasLen, 85374)
+}
diff --git a/pktline/decoder.go b/pktline/decoder.go
index db3fd72..76be108 100644
--- a/pktline/decoder.go
+++ b/pktline/decoder.go
@@ -2,6 +2,7 @@ package pktline
 
 import (
 	"errors"
+	"fmt"
 	"io"
 	"strconv"
 )
@@ -25,9 +26,10 @@ func (d *Decoder) readLine() (string, error) {
 	if _, err := d.r.Read(raw); err != nil {
 		return "", err
 	}
-
 	header, err := strconv.ParseInt(string(raw), 16, 16)
 	if err != nil {
+		fmt.Println(err)
+
 		return "", ErrInvalidHeader
 	}
 
diff --git a/remote.go b/remote.go
index 100bc5c..715d71e 100644
--- a/remote.go
+++ b/remote.go
@@ -1,6 +1,8 @@
 package git
 
 import (
+	"io"
+
 	"gopkg.in/src-d/go-git.v2/clients"
 	"gopkg.in/src-d/go-git.v2/clients/common"
 )
@@ -48,3 +50,15 @@ func (r *Remote) Capabilities() common.Capabilities {
 func (r *Remote) DefaultBranch() string {
 	return r.upInfo.Capabilities.SymbolicReference("HEAD")
 }
+
+// Fetch returns a reader using the request
+func (r *Remote) Fetch(req *common.GitUploadPackRequest) (io.ReadCloser, error) {
+	return r.upSrv.Fetch(req)
+}
+
+// FetchDefaultBranch returns a reader for the default branch
+func (r *Remote) FetchDefaultBranch() (io.ReadCloser, error) {
+	return r.Fetch(&common.GitUploadPackRequest{
+		Want: []string{r.upInfo.Refs[r.DefaultBranch()].Id},
+	})
+}
diff --git a/remote_test.go b/remote_test.go
index 511b690..3426fce 100644
--- a/remote_test.go
+++ b/remote_test.go
@@ -1,6 +1,9 @@
 package git
 
-import . "gopkg.in/check.v1"
+import (
+	. "gopkg.in/check.v1"
+	"gopkg.in/src-d/go-git.v2/packfile"
+)
 
 type SuiteRemote struct{}
 
@@ -27,3 +30,19 @@ func (s *SuiteRemote) TestCapabilities(c *C) {
 	c.Assert(r.Connect(), IsNil)
 	c.Assert(r.Capabilities().Get("agent"), HasLen, 1)
 }
+
+func (s *SuiteRemote) TestFetchDefaultBranch(c *C) {
+	r, err := NewRemote(RepositoryFixture)
+	c.Assert(err, IsNil)
+	c.Assert(r.Connect(), IsNil)
+
+	reader, err := r.FetchDefaultBranch()
+	c.Assert(err, IsNil)
+
+	pr, err := packfile.NewPackfileReader(reader, 8<<20, nil)
+	c.Assert(err, IsNil)
+
+	pf, err := pr.Read()
+	c.Assert(err, IsNil)
+	c.Assert(pf.ObjectCount, Equals, 28)
+}