Merge pull request #28 from mcuadros/memory-object

storages: memory object

Author: mcuadros

commit.go

@@ -51,6 +51,10 @@ func (c *Commit) File(path string) (file *File, err error) {
 
 // Decode transform an core.Object into a Blob struct
 func (c *Commit) Decode(o core.Object) error {
+	if o.Type() != core.CommitObject {
+		return ErrUnsupportedObject
+	}
+
 	c.Hash = o.Hash()
 	r := bufio.NewReader(o.Reader())
 

core/hash.go

@@ -9,6 +9,9 @@ import (
 // Hash SHA1 hased content
 type Hash [20]byte
 
+// ZeroHash is Hash with value zero
+var ZeroHash Hash
+
 // ComputeHash compute the hash for a given ObjectType and content
 func ComputeHash(t ObjectType, content []byte) Hash {
 	h := t.Bytes()

core/object.go

@@ -2,7 +2,6 @@
 package core
 
 import (
-	"bytes"
 	"errors"
 	"io"
 )
@@ -13,11 +12,11 @@ var (
 
 // Object is a generic representation of any git object
 type Object interface {
+	Hash() Hash
 	Type() ObjectType
 	SetType(ObjectType)
 	Size() int64
 	SetSize(int64)
-	Hash() Hash
 	Reader() io.Reader
 	Writer() io.Writer
 }
@@ -147,87 +146,3 @@ func (iter *ObjectSliceIter) Next() (Object, error) {
 func (iter *ObjectSliceIter) Close() {
 	iter.pos = len(iter.series)
 }
-
-type RAWObject struct {
-	b []byte
-	t ObjectType
-	s int64
-}
-
-func (o *RAWObject) Type() ObjectType     { return o.t }
-func (o *RAWObject) SetType(t ObjectType) { o.t = t }
-func (o *RAWObject) Size() int64          { return o.s }
-func (o *RAWObject) SetSize(s int64)      { o.s = s }
-func (o *RAWObject) Reader() io.Reader    { return bytes.NewBuffer(o.b) }
-func (o *RAWObject) Hash() Hash           { return ComputeHash(o.t, o.b) }
-func (o *RAWObject) Writer() io.Writer    { return o }
-func (o *RAWObject) Write(p []byte) (n int, err error) {
-	o.b = append(o.b, p...)
-	return len(p), nil
-}
-
-type RAWObjectStorage struct {
-	Objects map[Hash]Object
-	Commits map[Hash]Object
-	Trees   map[Hash]Object
-	Blobs   map[Hash]Object
-}
-
-func NewRAWObjectStorage() *RAWObjectStorage {
-	return &RAWObjectStorage{
-		Objects: make(map[Hash]Object, 0),
-		Commits: make(map[Hash]Object, 0),
-		Trees:   make(map[Hash]Object, 0),
-		Blobs:   make(map[Hash]Object, 0),
-	}
-}
-
-func (o *RAWObjectStorage) New() (Object, error) {
-	return &RAWObject{}, nil
-}
-
-func (o *RAWObjectStorage) Set(obj Object) (Hash, error) {
-	h := obj.Hash()
-	o.Objects[h] = obj
-
-	switch obj.Type() {
-	case CommitObject:
-		o.Commits[h] = o.Objects[h]
-	case TreeObject:
-		o.Trees[h] = o.Objects[h]
-	case BlobObject:
-		o.Blobs[h] = o.Objects[h]
-	}
-
-	return h, nil
-}
-
-func (o *RAWObjectStorage) Get(h Hash) (Object, error) {
-	obj, ok := o.Objects[h]
-	if !ok {
-		return nil, ObjectNotFoundErr
-	}
-
-	return obj, nil
-}
-
-func (o *RAWObjectStorage) Iter(t ObjectType) ObjectIter {
-	var series []Object
-	switch t {
-	case CommitObject:
-		series = flattenObjectMap(o.Commits)
-	case TreeObject:
-		series = flattenObjectMap(o.Trees)
-	case BlobObject:
-		series = flattenObjectMap(o.Blobs)
-	}
-	return NewObjectSliceIter(series)
-}
-
-func flattenObjectMap(m map[Hash]Object) []Object {
-	objects := make([]Object, 0, len(m))
-	for _, obj := range m {
-		objects = append(objects, obj)
-	}
-	return objects
-}

formats/packfile/reader.go

@@ -125,7 +125,7 @@ func (r *Reader) readObjects(count uint32) error {
 	// of which 12-20 % is _not_ zlib inflation (ie. is our code).
 	for i := 0; i < int(count); i++ {
 		start := r.r.position
-		obj, err := r.newRAWObject()
+		obj, err := r.newObject()
 		if err != nil && err != io.EOF {
 			return err
 		}
@@ -143,7 +143,7 @@ func (r *Reader) readObjects(count uint32) error {
 	return nil
 }
 
-func (r *Reader) newRAWObject() (core.Object, error) {
+func (r *Reader) newObject() (core.Object, error) {
 	raw, err := r.s.New()
 	if err != nil {
 		return nil, err

formats/packfile/reader_test.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"gopkg.in/src-d/go-git.v2/core"
+	"gopkg.in/src-d/go-git.v2/storages/memory"
 
 	"github.com/dustin/go-humanize"
 	. "gopkg.in/check.v1"
@@ -29,7 +30,7 @@ func (s *ReaderSuite) TestReadPackfile(c *C) {
 
 	r := NewReader(d)
 
-	storage := core.NewRAWObjectStorage()
+	storage := memory.NewObjectStorage()
 	_, err := r.Read(storage)
 	c.Assert(err, IsNil)
 
@@ -63,7 +64,7 @@ func (s *ReaderSuite) testReadPackfileGitFixture(c *C, file string, f Format) {
 	r := NewReader(d)
 	r.Format = f
 
-	storage := core.NewRAWObjectStorage()
+	storage := memory.NewObjectStorage()
 	_, err = r.Read(storage)
 	c.Assert(err, IsNil)
 
@@ -99,7 +100,7 @@ func (s *ReaderSuite) testReadPackfileGitFixture(c *C, file string, f Format) {
 	})
 }
 
-func AssertObjects(c *C, s *core.RAWObjectStorage, expects []string) {
+func AssertObjects(c *C, s *memory.ObjectStorage, expects []string) {
 	c.Assert(len(expects), Equals, len(s.Objects))
 	for _, expected := range expects {
 		obtained, err := s.Get(core.NewHash(expected))
@@ -174,14 +175,14 @@ func (s *ReaderSuite) _TestMemoryREF(c *C) {
 	fmt.Println("time", time.Since(start))
 }
 
-func readFromFile(c *C, file string, f Format) *core.RAWObjectStorage {
+func readFromFile(c *C, file string, f Format) *memory.ObjectStorage {
 	d, err := os.Open(file)
 	c.Assert(err, IsNil)
 
 	r := NewReader(d)
 	r.Format = f
 
-	storage := core.NewRAWObjectStorage()
+	storage := memory.NewObjectStorage()
 	_, err = r.Read(storage)
 	c.Assert(err, IsNil)
 

objects.go

@@ -1,6 +1,7 @@
 package git
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"strconv"
@@ -17,8 +18,14 @@ type Blob struct {
 	obj core.Object
 }
 
+var ErrUnsupportedObject = errors.New("unsupported object type")
+
 // Decode transform an core.Object into a Blob struct
 func (b *Blob) Decode(o core.Object) error {
+	if o.Type() != core.BlobObject {
+		return ErrUnsupportedObject
+	}
+
 	b.Hash = o.Hash()
 	b.Size = o.Size()
 	b.obj = o

objects_test.go

@@ -6,6 +6,7 @@ import (
 
 	. "gopkg.in/check.v1"
 	"gopkg.in/src-d/go-git.v2/core"
+	"gopkg.in/src-d/go-git.v2/storages/memory"
 )
 
 type ObjectsSuite struct {
@@ -71,7 +72,7 @@ func (s *ObjectsSuite) TestParseTree(c *C) {
 }
 
 func (s *ObjectsSuite) TestBlobHash(c *C) {
-	o := &core.RAWObject{}
+	o := &memory.Object{}
 	o.SetType(core.BlobObject)
 	o.SetSize(3)
 	o.Writer().Write([]byte{'F', 'O', 'O'})

remote_test.go

@@ -2,8 +2,8 @@ package git
 
 import (
 	"gopkg.in/src-d/go-git.v2/clients/http"
-	"gopkg.in/src-d/go-git.v2/core"
 	"gopkg.in/src-d/go-git.v2/formats/packfile"
+	"gopkg.in/src-d/go-git.v2/storages/memory"
 
 	. "gopkg.in/check.v1"
 )
@@ -57,7 +57,7 @@ func (s *SuiteRemote) TestFetchDefaultBranch(c *C) {
 
 	pr := packfile.NewReader(reader)
 
-	storage := core.NewRAWObjectStorage()
+	storage := memory.NewObjectStorage()
 	_, err = pr.Read(storage)
 	c.Assert(err, IsNil)
 	c.Assert(storage.Objects, HasLen, 28)

repository.go

@@ -7,6 +7,7 @@ import (
 	"gopkg.in/src-d/go-git.v2/clients/common"
 	"gopkg.in/src-d/go-git.v2/core"
 	"gopkg.in/src-d/go-git.v2/formats/packfile"
+	"gopkg.in/src-d/go-git.v2/storages/memory"
 )
 
 var (
@@ -49,7 +50,7 @@ func NewRepository(url string, auth common.AuthMethod) (*Repository, error) {
 func NewPlainRepository() *Repository {
 	return &Repository{
 		Remotes: map[string]*Remote{},
-		Storage: core.NewRAWObjectStorage(),
+		Storage: memory.NewObjectStorage(),
 	}
 }
 

storage/memory/object.go

@@ -0,0 +1,55 @@
+package memory
+
+import (
+	"bytes"
+	"io"
+
+	"gopkg.in/src-d/go-git.v2/core"
+)
+
+// Object on memory core.Object implementation
+type Object struct {
+	t       core.ObjectType
+	h       core.Hash
+	content []byte
+	size    int64
+}
+
+// Hash return the object Hash, the hash is calculated on-the-fly the first
+// time is called, the subsequent calls the same Hash is returned even in the
+// type or the content has changed. The Hash is only generated if the size of
+// the content is exactly the Object.Size
+func (o *Object) Hash() core.Hash {
+	if o.h == core.ZeroHash && int64(len(o.content)) == o.size {
+		o.h = core.ComputeHash(o.t, o.content)
+	}
+
+	return o.h
+}
+
+// Type return the core.ObjectType
+func (o *Object) Type() core.ObjectType { return o.t }
+
+// SetType sets the core.ObjectType
+func (o *Object) SetType(t core.ObjectType) { o.t = t }
+
+// Size return the size of the object
+func (o *Object) Size() int64 { return o.size }
+
+// SetSize set the object size, the given size should be written afterwards
+func (o *Object) SetSize(s int64) { o.size = s }
+
+// Reader returns a io.Reader used to read the object content
+func (o *Object) Reader() io.Reader {
+	return bytes.NewBuffer(o.content)
+}
+
+// Writer returns a io.Writed used to write the object content
+func (o *Object) Writer() io.Writer {
+	return o
+}
+
+func (o *Object) Write(p []byte) (n int, err error) {
+	o.content = append(o.content, p...)
+	return len(p), nil
+}