Submodules init and update

storage/filesystem/internal/dotgit/dotgit.go

@@ -20,10 +20,10 @@ const (
 	configPath     = "config"
 	indexPath      = "index"
 	shallowPath    = "shallow"
-
-	objectsPath = "objects"
-	packPath    = "pack"
-	refsPath    = "refs"
+	modulePath     = "module"
+	objectsPath    = "objects"
+	packPath       = "pack"
+	refsPath       = "refs"
 
 	packExt = ".pack"
 	idxExt  = ".idx"
@@ -390,6 +390,11 @@ func (d *DotGit) readReferenceFile(refsPath, refFile string) (ref *plumbing.Refe
 	return plumbing.NewReferenceFromStrings(refFile, line), nil
 }
 
+// Module return a billy.Filesystem poiting to the module folder
+func (d *DotGit) Module(name string) billy.Filesystem {
+	return d.fs.Dir(d.fs.Join(modulePath, name))
+}
+
 func isHex(s string) bool {
 	for _, b := range []byte(s) {
 		if isNum(b) {

storage/filesystem/module.go

@@ -0,0 +1,14 @@
+package filesystem
+
+import (
+	"srcd.works/go-git.v4/storage"
+	"srcd.works/go-git.v4/storage/filesystem/internal/dotgit"
+)
+
+type ModuleStorage struct {
+	dir *dotgit.DotGit
+}
+
+func (s *ModuleStorage) Module(name string) (storage.Storer, error) {
+	return NewStorage(s.dir.Module(name))
+}

storage/filesystem/storage.go

@@ -16,6 +16,7 @@ type Storage struct {
 	IndexStorage
 	ShallowStorage
 	ConfigStorage
+	ModuleStorage
 }
 
 // NewStorage returns a new Storage backed by a given `fs.Filesystem`
@@ -32,5 +33,6 @@ func NewStorage(fs billy.Filesystem) (*Storage, error) {
 		IndexStorage:     IndexStorage{dir: dir},
 		ShallowStorage:   ShallowStorage{dir: dir},
 		ConfigStorage:    ConfigStorage{dir: dir},
+		ModuleStorage:    ModuleStorage{dir: dir},
 	}, nil
 }

storage/memory/storage.go

@@ -8,6 +8,7 @@ import (
 	"srcd.works/go-git.v4/plumbing"
 	"srcd.works/go-git.v4/plumbing/format/index"
 	"srcd.works/go-git.v4/plumbing/storer"
+	"srcd.works/go-git.v4/storage"
 )
 
 var ErrUnsupportedObjectType = fmt.Errorf("unsupported object type")
@@ -22,6 +23,7 @@ type Storage struct {
 	ShallowStorage
 	IndexStorage
 	ReferenceStorage
+	ModuleStorage
 }
 
 // NewStorage returns a new Storage base on memory
@@ -37,6 +39,7 @@ func NewStorage() *Storage {
 			Blobs:   make(map[plumbing.Hash]plumbing.EncodedObject, 0),
 			Tags:    make(map[plumbing.Hash]plumbing.EncodedObject, 0),
 		},
+		ModuleStorage: make(ModuleStorage, 0),
 	}
 }
 
@@ -227,3 +230,13 @@ func (s *ShallowStorage) SetShallow(commits []plumbing.Hash) error {
 func (s ShallowStorage) Shallow() ([]plumbing.Hash, error) {
 	return s, nil
 }
+
+type ModuleStorage map[string]*Storage
+
+func (s ModuleStorage) Module(name string) (storage.Storer, error) {
+	if _, ok := s[name]; !ok {
+		s[name] = NewStorage()
+	}
+
+	return s[name], nil
+}

storage/storer.go

@@ -0,0 +1,23 @@
+package storage
+
+import (
+	"srcd.works/go-git.v4/config"
+	"srcd.works/go-git.v4/plumbing/storer"
+)
+
+// Storer is a generic storage of objects, references and any information
+// related to a particular repository. The package srcd.works/go-git.v4/storage
+// contains two implementation a filesystem base implementation (such as `.git`)
+// and a memory implementations being ephemeral
+type Storer interface {
+	storer.EncodedObjectStorer
+	storer.ReferenceStorer
+	storer.ShallowStorer
+	storer.IndexStorer
+	config.ConfigStorer
+	ModuleStorer
+}
+
+type ModuleStorer interface {
+	Module(name string) (Storer, error)
+}

storage/test/storage_suite.go

@@ -11,6 +11,7 @@ import (
 	"srcd.works/go-git.v4/plumbing"
 	"srcd.works/go-git.v4/plumbing/format/index"
 	"srcd.works/go-git.v4/plumbing/storer"
+	"srcd.works/go-git.v4/storage"
 
 	. "gopkg.in/check.v1"
 )
@@ -21,6 +22,8 @@ type Storer interface {
 	storer.ShallowStorer
 	storer.IndexStorer
 	config.ConfigStorer
+
+	storage.ModuleStorer
 }
 
 type TestObject struct {
@@ -326,6 +329,16 @@ func (s *BaseStorageSuite) TestSetConfigInvalid(c *C) {
 	c.Assert(err, NotNil)
 }
 
+func (s *BaseStorageSuite) TestModule(c *C) {
+	storer, err := s.Storer.Module("foo")
+	c.Assert(err, IsNil)
+	c.Assert(storer, NotNil)
+
+	storer, err = s.Storer.Module("foo")
+	c.Assert(err, IsNil)
+	c.Assert(storer, NotNil)
+}
+
 func objectEquals(a plumbing.EncodedObject, b plumbing.EncodedObject) error {
 	ha := a.Hash()
 	hb := b.Hash()