feat: Add archive capability

5 files changed, 190 insertions, 1 deletions

diff --git a/pkg/ext/mime.go b/pkg/ext/mime.go
index 6da66e3..c42d4de 100644
--- a/pkg/ext/mime.go
+++ b/pkg/ext/mime.go
@@ -5,7 +5,8 @@ import "net/http"
 type ContentType = string
 
 const (
-	TextHTML ContentType = "text/html"
+	TextHTML        ContentType = "text/html"
+	ApplicationGZip ContentType = "application/gzip"
 )
 
 func Html(next func(w http.ResponseWriter, r *http.Request)) func(w http.ResponseWriter, r *http.Request) {
@@ -14,9 +15,17 @@ func Html(next func(w http.ResponseWriter, r *http.Request)) func(w http.Respons
 	}
 }
 
+func SetFileName(w http.ResponseWriter, name string) {
+	h := "inline; filename=\"" + name + "\""
+	w.Header().Add("Content-Disposition", h)
+}
+
 func SetHTML(w http.ResponseWriter) {
 	SetMIME(w, TextHTML)
+}
 
+func SetGZip(w http.ResponseWriter) {
+	SetMIME(w, ApplicationGZip)
 }
 
 func SetMIME(w http.ResponseWriter, mime ContentType) {
diff --git a/pkg/git/git.go b/pkg/git/git.go
index b725cd8..591fafb 100644
--- a/pkg/git/git.go
+++ b/pkg/git/git.go
@@ -1,9 +1,13 @@
 package git
 
 import (
+	"archive/tar"
 	"errors"
 	"fmt"
 	"io"
+	"io/fs"
+	"path"
+	"time"
 
 	"github.com/go-git/go-git/v5"
 	"github.com/go-git/go-git/v5/plumbing"
@@ -26,6 +30,13 @@ type (
 		// this is setRef when ref is setRef
 		setRef bool
 	}
+	infoWrapper struct {
+		name    string
+		size    int64
+		mode    fs.FileMode
+		modTime time.Time
+		isDir   bool
+	}
 )
 
 func OpenRepository(dir string) (*GitRepository, error) {
@@ -213,3 +224,110 @@ func (g *GitRepository) FileContent(path string) (string, error) {
 		return "Binary file", nil
 	}
 }
+
+func (g *GitRepository) WriteTar(w io.Writer, prefix string) error {
+	tw := tar.NewWriter(w)
+	defer tw.Close()
+
+	tree, err := g.Tree("")
+	if err != nil {
+		return err
+	}
+
+	walker := object.NewTreeWalker(tree, true, nil)
+	defer walker.Close()
+
+	name, entry, err := walker.Next()
+	for ; err == nil; name, entry, err = walker.Next() {
+		info, err := newInfoWrapper(name, prefix, &entry, tree)
+		if err != nil {
+			return err
+		}
+
+		header, err := tar.FileInfoHeader(info, "")
+		if err != nil {
+			return err
+		}
+
+		err = tw.WriteHeader(header)
+		if err != nil {
+			return err
+		}
+
+		if !info.IsDir() {
+			c, err := g.FileContent(name)
+			if err != nil {
+				return err
+			}
+
+			_, err = tw.Write([]byte(c))
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func newInfoWrapper(
+	filename string,
+	prefix string,
+	entry *object.TreeEntry,
+	tree *object.Tree,
+) (*infoWrapper, error) {
+	var (
+		size  int64
+		mode  fs.FileMode
+		isDir bool
+	)
+
+	if entry.Mode.IsFile() {
+		file, err := tree.TreeEntryFile(entry)
+		if err != nil {
+			return nil, err
+		}
+		mode = fs.FileMode(file.Mode)
+
+		size, err = tree.Size(filename)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		isDir = true
+		mode = fs.ModeDir | fs.ModePerm
+	}
+
+	fullname := path.Join(prefix, filename)
+	return &infoWrapper{
+		name:    fullname,
+		size:    size,
+		mode:    mode,
+		modTime: time.Unix(0, 0),
+		isDir:   isDir,
+	}, nil
+}
+
+func (i *infoWrapper) Name() string {
+	return i.name
+}
+
+func (i *infoWrapper) Size() int64 {
+	return i.size
+}
+
+func (i *infoWrapper) Mode() fs.FileMode {
+	return i.mode
+}
+
+func (i *infoWrapper) ModTime() time.Time {
+	return i.modTime
+}
+
+func (i *infoWrapper) IsDir() bool {
+	return i.isDir
+}
+
+func (i *infoWrapper) Sys() any {
+	return nil
+}
diff --git a/pkg/handler/git/handler.go b/pkg/handler/git/handler.go
index 25505ba..aed9917 100644
--- a/pkg/handler/git/handler.go
+++ b/pkg/handler/git/handler.go
@@ -2,10 +2,13 @@ package git
 
 import (
 	"bytes"
+	"fmt"
 	"io"
+	"log/slog"
 	"net/http"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"git.gabrielgio.me/cerrado/pkg/ext"
 	"git.gabrielgio.me/cerrado/pkg/service"
@@ -36,6 +39,7 @@ type (
 		GetAbout(name string) (string, error)
 		ListTags(name string) ([]*plumbing.Reference, error)
 		ListBranches(name string) ([]*plumbing.Reference, error)
+		WriteTarGZip(w io.Writer, name, ref, filename string) error
 	}
 
 	configurationRepository interface {
@@ -84,6 +88,38 @@ func (g *GitHandler) List(w http.ResponseWriter, _ *http.Request) error {
 	return nil
 }
 
+func (g *GitHandler) Archive(w http.ResponseWriter, r *http.Request) error {
+	ext.SetGZip(w)
+	name := r.PathValue("name")
+	refs := r.PathValue("refs")
+	ref := strings.TrimSuffix(refs, ".tar.gz")
+
+	// TODO: remove it once we can support more than gzip
+	if !strings.HasSuffix(refs, ".tar.gz") {
+		ext.NotFound(w)
+		return nil
+	}
+
+	filenameWithExt := fmt.Sprintf("%s-%s.tar.gz", name, ref)
+	ext.SetFileName(w, filenameWithExt)
+	filename := fmt.Sprintf("%s-%s", name, ref)
+
+	// writing to a buffer so we can run all the process before writing error
+	var buf bytes.Buffer
+	err := g.gitService.WriteTarGZip(&buf, name, ref, filename)
+	if err != nil {
+		return err
+	}
+
+	// since that has write to w it cannot return a error.
+	_, err = io.Copy(w, &buf)
+	if err != nil {
+		slog.Error("Error copying buffer", "error", err)
+	}
+
+	return nil
+}
+
 func (g *GitHandler) Summary(w http.ResponseWriter, r *http.Request) error {
 	ext.SetHTML(w)
 	name := r.PathValue("name")
diff --git a/pkg/handler/router.go b/pkg/handler/router.go
index c8f8984..2293ab6 100644
--- a/pkg/handler/router.go
+++ b/pkg/handler/router.go
@@ -41,6 +41,7 @@ func MountHandler(
 	mux.HandleFunc("/{name}/tree/{ref}/{rest...}", gitHandler.Tree)
 	mux.HandleFunc("/{name}/blob/{ref}/{rest...}", gitHandler.Blob)
 	mux.HandleFunc("/{name}/log/{ref}/", gitHandler.Log)
+	mux.HandleFunc("/{name}/archive/{refs...}", gitHandler.Archive)
 	mux.HandleFunc("/config", configHandler)
 	mux.HandleFunc("/about", aboutHandler.About)
 	mux.HandleFunc("/", gitHandler.List)
diff --git a/pkg/service/git.go b/pkg/service/git.go
index 6bb6e9e..cbee90a 100644
--- a/pkg/service/git.go
+++ b/pkg/service/git.go
@@ -1,7 +1,9 @@
 package service
 
 import (
+	"compress/gzip"
 	"errors"
+	"io"
 	"log/slog"
 
 	"git.gabrielgio.me/cerrado/pkg/config"
@@ -92,6 +94,29 @@ func (g *GitService) ListCommits(name, ref string, count int) ([]*object.Commit,
 	return repo.Commits(count)
 }
 
+func (g *GitService) WriteTarGZip(w io.Writer, name, ref string, filename string) error {
+	r := g.configRepo.GetByName(name)
+	if r == nil {
+		return RepositoryNotFoundErr
+	}
+
+	repo, err := git.OpenRepository(r.Path)
+	if err != nil {
+		return err
+	}
+
+	err = repo.SetRef(ref)
+	if err != nil {
+		return err
+	}
+
+	gw := gzip.NewWriter(w)
+	defer gw.Close()
+
+	return repo.WriteTar(gw, filename)
+
+}
+
 func (g *GitService) GetTree(name, ref, path string) (*object.Tree, error) {
 	r := g.configRepo.GetByName(name)
 	if r == nil {