1 files changed, 104 insertions, 8 deletions
diff --git a/repository.go b/repository.go
index b159ff0..7cdc0d5 100644
--- a/repository.go
+++ b/repository.go
@@ -8,10 +8,12 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"gopkg.in/src-d/go-git.v4/config"
 	"gopkg.in/src-d/go-git.v4/internal/revision"
 	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
 	"gopkg.in/src-d/go-git.v4/plumbing/object"
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 	"gopkg.in/src-d/go-git.v4/storage"
@@ -23,14 +25,15 @@ import (
 )
 
 var (
-	ErrInvalidReference        = errors.New("invalid reference, should be a tag or a branch")
-	ErrRepositoryNotExists     = errors.New("repository does not exist")
-	ErrRepositoryAlreadyExists = errors.New("repository already exists")
-	ErrRemoteNotFound          = errors.New("remote not found")
-	ErrRemoteExists            = errors.New("remote already exists	")
-	ErrWorktreeNotProvided     = errors.New("worktree should be provided")
-	ErrIsBareRepository        = errors.New("worktree not available in a bare repository")
-	ErrUnableToResolveCommit   = errors.New("unable to resolve commit")
+	ErrInvalidReference          = errors.New("invalid reference, should be a tag or a branch")
+	ErrRepositoryNotExists       = errors.New("repository does not exist")
+	ErrRepositoryAlreadyExists   = errors.New("repository already exists")
+	ErrRemoteNotFound            = errors.New("remote not found")
+	ErrRemoteExists              = errors.New("remote already exists	")
+	ErrWorktreeNotProvided       = errors.New("worktree should be provided")
+	ErrIsBareRepository          = errors.New("worktree not available in a bare repository")
+	ErrUnableToResolveCommit     = errors.New("unable to resolve commit")
+	ErrPackedObjectsNotSupported = errors.New("Packed objects not supported")
 )
 
 // Repository represents a git repository
@@ -1011,3 +1014,96 @@ func (r *Repository) ResolveRevision(rev plumbing.Revision) (*plumbing.Hash, err
 
 	return &commit.Hash, nil
 }
+
+type RepackConfig struct {
+	// UseRefDeltas configures whether packfile encoder will use reference deltas.
+	// By default OFSDeltaObject is used.
+	UseRefDeltas bool
+	// OnlyDeletePacksOlderThan if set to non-zero value
+	// selects only objects older than the time provided.
+	OnlyDeletePacksOlderThan time.Time
+}
+
+func (r *Repository) RepackObjects(cfg *RepackConfig) (err error) {
+	pos, ok := r.Storer.(storer.PackedObjectStorer)
+	if !ok {
+		return ErrPackedObjectsNotSupported
+	}
+
+	// Get the existing object packs.
+	hs, err := pos.ObjectPacks()
+	if err != nil {
+		return err
+	}
+
+	// Create a new pack.
+	nh, err := r.createNewObjectPack(cfg)
+	if err != nil {
+		return err
+	}
+
+	// Delete old packs.
+	for _, h := range hs {
+		// Skip if new hash is the same as an old one.
+		if h == nh {
+			continue
+		}
+		err = pos.DeleteOldObjectPackAndIndex(h, cfg.OnlyDeletePacksOlderThan)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// createNewObjectPack is a helper for RepackObjects taking care
+// of creating a new pack. It is used so the the PackfileWriter
+// deferred close has the right scope.
+func (r *Repository) createNewObjectPack(cfg *RepackConfig) (h plumbing.Hash, err error) {
+	ow := newObjectWalker(r.Storer)
+	err = ow.walkAllRefs()
+	if err != nil {
+		return h, err
+	}
+	objs := make([]plumbing.Hash, 0, len(ow.seen))
+	for h := range ow.seen {
+		objs = append(objs, h)
+	}
+	pfw, ok := r.Storer.(storer.PackfileWriter)
+	if !ok {
+		return h, fmt.Errorf("Repository storer is not a storer.PackfileWriter")
+	}
+	wc, err := pfw.PackfileWriter()
+	if err != nil {
+		return h, err
+	}
+	defer ioutil.CheckClose(wc, &err)
+	scfg, err := r.Storer.Config()
+	if err != nil {
+		return h, err
+	}
+	enc := packfile.NewEncoder(wc, r.Storer, cfg.UseRefDeltas)
+	h, err = enc.Encode(objs, scfg.Pack.Window)
+	if err != nil {
+		return h, err
+	}
+
+	// Delete the packed, loose objects.
+	if los, ok := r.Storer.(storer.LooseObjectStorer); ok {
+		err = los.ForEachObjectHash(func(hash plumbing.Hash) error {
+			if ow.isSeen(hash) {
+				err := los.DeleteLooseObject(hash)
+				if err != nil {
+					return err
+				}
+			}
+			return nil
+		})
+		if err != nil {
+			return h, err
+		}
+	}
+
+	return h, err
+}