git: pure go git clone

2 files changed, 117 insertions, 27 deletions

diff --git a/routes/git.go b/routes/git.go
new file mode 100644
index 0000000..1a5e035
--- /dev/null
+++ b/routes/git.go
@@ -0,0 +1,108 @@
+package routes
+
+import (
+	"errors"
+	"log"
+	"net/http"
+	"path/filepath"
+
+	"github.com/alexedwards/flow"
+	"github.com/go-git/go-billy/v5/osfs"
+	"github.com/go-git/go-git/v5/plumbing/format/pktline"
+	"github.com/go-git/go-git/v5/plumbing/protocol/packp"
+	"github.com/go-git/go-git/v5/plumbing/transport"
+	"github.com/go-git/go-git/v5/plumbing/transport/server"
+)
+
+func (d *deps) InfoRefs(w http.ResponseWriter, r *http.Request) {
+	name := flow.Param(r.Context(), "name")
+	name = filepath.Clean(name)
+
+	repo := filepath.Join(d.c.Repo.ScanPath, name)
+
+	w.Header().Set("content-type", "application/x-git-upload-pack-advertisement")
+
+	ep, err := transport.NewEndpoint("/")
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	billyfs := osfs.New(repo)
+	loader := server.NewFilesystemLoader(billyfs)
+	srv := server.NewServer(loader)
+	session, err := srv.NewUploadPackSession(ep, nil)
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	ar, err := session.AdvertisedReferencesContext(r.Context())
+	if errors.Is(err, transport.ErrRepositoryNotFound) {
+		http.Error(w, err.Error(), 404)
+		return
+	} else if err != nil {
+		http.Error(w, err.Error(), 500)
+		return
+	}
+
+	ar.Prefix = [][]byte{
+		[]byte("# service=git-upload-pack"),
+		pktline.Flush,
+	}
+
+	if err = ar.Encode(w); err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+}
+
+func (d *deps) UploadPack(w http.ResponseWriter, r *http.Request) {
+	name := flow.Param(r.Context(), "name")
+	name = filepath.Clean(name)
+
+	repo := filepath.Join(d.c.Repo.ScanPath, name)
+
+	w.Header().Set("content-type", "application/x-git-upload-pack-result")
+
+	upr := packp.NewUploadPackRequest()
+	err := upr.Decode(r.Body)
+	if err != nil {
+		http.Error(w, err.Error(), 400)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	ep, err := transport.NewEndpoint("/")
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	billyfs := osfs.New(repo)
+	loader := server.NewFilesystemLoader(billyfs)
+	svr := server.NewServer(loader)
+	session, err := svr.NewUploadPackSession(ep, nil)
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	res, err := session.UploadPack(r.Context(), upr)
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+
+	if err = res.Encode(w); err != nil {
+		http.Error(w, err.Error(), 500)
+		log.Printf("git: %s", err)
+		return
+	}
+}
diff --git a/routes/handler.go b/routes/handler.go
index c0b146c..a0e7832 100644
--- a/routes/handler.go
+++ b/routes/handler.go
@@ -1,26 +1,16 @@
 package routes
 
 import (
-	"log"
 	"net/http"
-	"path/filepath"
 
 	"git.icyphox.sh/legit/config"
 	"github.com/alexedwards/flow"
-	"github.com/sosedoff/gitkit"
 )
 
-type depsWrapper struct {
-	actualDeps deps
-	gitsvc     *gitkit.Server
-}
-
 // Checks for gitprotocol-http(5) specific smells; if found, passes
 // the request on to the git http service, else render the web frontend.
-func (dw *depsWrapper) Multiplex(w http.ResponseWriter, r *http.Request) {
+func (d *deps) Multiplex(w http.ResponseWriter, r *http.Request) {
 	path := flow.Param(r.Context(), "...")
-	name := flow.Param(r.Context(), "name")
-	name = filepath.Clean(name)
 
 	if r.URL.RawQuery == "service=git-receive-pack" {
 		w.WriteHeader(http.StatusBadRequest)
@@ -28,12 +18,14 @@ func (dw *depsWrapper) Multiplex(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if path == "info/refs" && r.URL.RawQuery == "service=git-upload-pack" && r.Method == "GET" {
-		dw.gitsvc.ServeHTTP(w, r)
+	if path == "info/refs" &&
+		r.URL.RawQuery == "service=git-upload-pack" &&
+		r.Method == "GET" {
+		d.InfoRefs(w, r)
 	} else if path == "git-upload-pack" && r.Method == "POST" {
-		dw.gitsvc.ServeHTTP(w, r)
+		d.UploadPack(w, r)
 	} else if r.Method == "GET" {
-		dw.actualDeps.RepoIndex(w, r)
+		d.RepoIndex(w, r)
 	}
 }
 
@@ -41,29 +33,19 @@ func Handlers(c *config.Config) *flow.Mux {
 	mux := flow.New()
 	d := deps{c}
 
-	gitsvc := gitkit.New(gitkit.Config{
-		Dir:        c.Repo.ScanPath,
-		AutoCreate: false,
-	})
-	if err := gitsvc.Setup(); err != nil {
-		log.Fatalf("git server: %s", err)
-	}
-
-	dw := depsWrapper{actualDeps: d, gitsvc: gitsvc}
-
 	mux.NotFound = http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 		d.Write404(w)
 	})
 
 	mux.HandleFunc("/", d.Index, "GET")
 	mux.HandleFunc("/static/:file", d.ServeStatic, "GET")
-	mux.HandleFunc("/:name", dw.Multiplex, "GET", "POST")
+	mux.HandleFunc("/:name", d.Multiplex, "GET", "POST")
 	mux.HandleFunc("/:name/tree/:ref/...", d.RepoTree, "GET")
 	mux.HandleFunc("/:name/blob/:ref/...", d.FileContent, "GET")
 	mux.HandleFunc("/:name/log/:ref", d.Log, "GET")
 	mux.HandleFunc("/:name/commit/:ref", d.Diff, "GET")
 	mux.HandleFunc("/:name/refs", d.Refs, "GET")
-	mux.HandleFunc("/:name/...", dw.Multiplex, "GET", "POST")
+	mux.HandleFunc("/:name/...", d.Multiplex, "GET", "POST")
 
 	return mux
 }