global storage interface refactor (#112)

* core: ObjectStorage, ReferenceStorage renamed to ObjectStorer and
ReferenceStorer

* rebase

* general, changes request by @alcortes

* general, changes request by @alcortes

Author: mcuadros

blobs.go

@@ -60,7 +60,7 @@ func (b *Blob) Encode(o core.Object) error {
 }
 
 // Reader returns a reader allow the access to the content of the blob
-func (b *Blob) Reader() (core.ObjectReader, error) {
+func (b *Blob) Reader() (io.ReadCloser, error) {
 	return b.obj.Reader()
 }
 

clients/common/common.go

@@ -110,10 +110,9 @@ func (i *GitUploadPackInfo) Decode(r io.Reader) error {
 }
 
 func (i *GitUploadPackInfo) addRefs(ar *advrefs.AdvRefs) error {
-	i.Refs = make(memory.ReferenceStorage, 0)
 	for name, hash := range ar.References {
 		ref := core.NewReferenceFromStrings(name, hash.String())
-		i.Refs.Set(ref)
+		i.Refs.SetReference(ref)
 	}
 
 	return i.addSymbolicRefs(ar)
@@ -133,7 +132,7 @@ func (i *GitUploadPackInfo) addSymbolicRefs(ar *advrefs.AdvRefs) error {
 		name := core.ReferenceName(chunks[0])
 		target := core.ReferenceName(chunks[1])
 		ref := core.NewSymbolicReference(name, target)
-		i.Refs.Set(ref)
+		i.Refs.SetReference(ref)
 	}
 
 	return nil

commit.go

@@ -37,11 +37,9 @@ func (c *Commit) Tree() (*Tree, error) {
 
 // Parents return a CommitIter to the parent Commits
 func (c *Commit) Parents() *CommitIter {
-	return NewCommitIter(c.r, core.NewObjectLookupIter(
-		c.r.s.ObjectStorage(),
-		core.CommitObject,
-		c.parents,
-	))
+	return NewCommitIter(c.r,
+		core.NewObjectLookupIter(c.r.s, core.CommitObject, c.parents),
+	)
 }
 
 // NumParents returns the number of parents in a commit.

commit_test.go

@@ -29,7 +29,7 @@ func (s *SuiteCommit) SetUpSuite(c *C) {
 
 func (s *SuiteCommit) TestDecodeNonCommit(c *C) {
 	hash := core.NewHash("9a48f23120e880dfbe41f7c9b7b708e9ee62a492")
-	blob, err := s.Repository.s.ObjectStorage().Get(core.AnyObject, hash)
+	blob, err := s.Repository.s.Object(core.AnyObject, hash)
 	c.Assert(err, IsNil)
 
 	commit := &Commit{}

common.go

@@ -8,11 +8,14 @@ import (
 	"gopkg.in/src-d/go-git.v4/core"
 )
 
-// Storage storage of objects and references
-type Storage interface {
-	ConfigStorage() config.ConfigStorage
-	ObjectStorage() core.ObjectStorage
-	ReferenceStorage() core.ReferenceStorage
+// Storer is a generic storage of objects, references and any information
+// related to a particular repository. Some Storer implementations persist the
+// information in an system directory (such as `.git`) and others
+// implementations are in memmory being ephemeral
+type Storer interface {
+	core.ObjectStorer
+	core.ReferenceStorer
+	config.ConfigStorer
 }
 
 // countLines returns the number of lines in a string à la git, this is
@@ -52,4 +55,5 @@ func checkClose(c io.Closer, err *error) {
 	}
 }
 
+// DateFormat is the format being use in the orignal git implementation
 const DateFormat = "Mon Jan 02 15:04:05 2006 -0700"

common_test.go

@@ -57,7 +57,7 @@ func (s *BaseSuite) buildRepositories(c *C, f fixtures.Fixtures) {
 		defer f.Close()
 
 		n := packfile.NewScanner(f)
-		d, err := packfile.NewDecoder(n, r.s.ObjectStorage())
+		d, err := packfile.NewDecoder(n, r.s)
 		c.Assert(err, IsNil)
 		_, err = d.Decode()
 		c.Assert(err, IsNil)
@@ -155,7 +155,7 @@ func unpackFixtures(c *C, fixtures ...[]packedFixture) map[string]*Repository {
 			c.Assert(err, IsNil, comment)
 
 			r := packfile.NewScanner(f)
-			d, err := packfile.NewDecoder(r, repos[fixture.url].s.ObjectStorage())
+			d, err := packfile.NewDecoder(r, repos[fixture.url].s)
 			c.Assert(err, IsNil, comment)
 			_, err = d.Decode()
 			c.Assert(err, IsNil, comment)

config/config.go

@@ -7,22 +7,51 @@ import (
 )
 
 const (
+	// DefaultRefSpec is the default refspec used, when none is given
 	DefaultRefSpec = "+refs/heads/*:refs/remotes/%s/*"
 )
 
+// ConfigStorer interface to persist Config objects
+type ConfigStorer interface {
+	Config() (*Config, error)
+	SetConfig(*Config) error
+}
+
 var (
+	ErrInvalid               = errors.New("config invalid remote")
 	ErrRemoteConfigNotFound  = errors.New("remote config not found")
 	ErrRemoteConfigEmptyURL  = errors.New("remote config: empty URL")
 	ErrRemoteConfigEmptyName = errors.New("remote config: empty name")
 )
 
-type ConfigStorage interface {
-	Remote(name string) (*RemoteConfig, error)
-	Remotes() ([]*RemoteConfig, error)
-	SetRemote(*RemoteConfig) error
-	DeleteRemote(name string) error
+// Config contains the repository configuration
+type Config struct {
+	Remotes map[string]*RemoteConfig
+}
+
+// NewConfig returns a new empty Config
+func NewConfig() *Config {
+	return &Config{
+		Remotes: make(map[string]*RemoteConfig, 0),
+	}
+}
+
+// Validate validate the fields and set the default values
+func (c *Config) Validate() error {
+	for name, r := range c.Remotes {
+		if r.Name != name {
+			return ErrInvalid
+		}
+
+		if err := r.Validate(); err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
+// RemoteConfig contains the configuration for a given repository
 type RemoteConfig struct {
 	Name  string
 	URL   string

config/config_test.go

@@ -6,6 +6,26 @@ type ConfigSuite struct{}
 
 var _ = Suite(&ConfigSuite{})
 
+func (s *ConfigSuite) TestConfigValidateInvalidRemote(c *C) {
+	config := &Config{
+		Remotes: map[string]*RemoteConfig{
+			"foo": {Name: "foo"},
+		},
+	}
+
+	c.Assert(config.Validate(), Equals, ErrRemoteConfigEmptyURL)
+}
+
+func (s *ConfigSuite) TestConfigValidateInvalidKey(c *C) {
+	config := &Config{
+		Remotes: map[string]*RemoteConfig{
+			"bar": {Name: "foo"},
+		},
+	}
+
+	c.Assert(config.Validate(), Equals, ErrInvalid)
+}
+
 func (s *ConfigSuite) TestRemoteConfigValidateMissingURL(c *C) {
 	config := &RemoteConfig{Name: "foo"}
 	c.Assert(config.Validate(), Equals, ErrRemoteConfigEmptyURL)

core/memory.go

@@ -1,7 +1,8 @@
-package core 
+package core
 
 import (
 	"bytes"
+	"io"
 	"io/ioutil"
 )
 
@@ -39,12 +40,12 @@ func (o *MemoryObject) Size() int64 { return o.sz }
 func (o *MemoryObject) SetSize(s int64) { o.sz = s }
 
 // Reader returns a ObjectReader used to read the object's content.
-func (o *MemoryObject) Reader() (ObjectReader, error) {
+func (o *MemoryObject) Reader() (io.ReadCloser, error) {
 	return ioutil.NopCloser(bytes.NewBuffer(o.cont)), nil
 }
 
 // Writer returns a ObjectWriter used to write the object's content.
-func (o *MemoryObject) Writer() (ObjectWriter, error) {
+func (o *MemoryObject) Writer() (io.WriteCloser, error) {
 	return o, nil
 }
 

core/object.go

@@ -12,30 +12,15 @@ var (
 	ErrInvalidType = errors.New("invalid object type")
 )
 
-// TODO: Consider adding a Hash function to the ObjectReader and ObjectWriter
-//       interfaces that returns the hash calculated for the reader or writer.
-
-// ObjectReader is a generic representation of an object reader.
-//
-// ObjectReader implements io.ReadCloser. Close should be called when finished
-// with it.
-type ObjectReader io.ReadCloser
-
-// ObjectWriter is a generic representation of an object writer.
-//
-// ObjectWriter implements io.WriterCloser. Close should be called when finished
-// with it.
-type ObjectWriter io.WriteCloser
-
 // Object is a generic representation of any git object
 type Object interface {
 	Hash() Hash
 	Type() ObjectType
 	SetType(ObjectType)
 	Size() int64
 	SetSize(int64)
-	Reader() (ObjectReader, error)
-	Writer() (ObjectWriter, error)
+	Reader() (io.ReadCloser, error)
+	Writer() (io.WriteCloser, error)
 }
 
 // ObjectType internal object type
@@ -116,15 +101,15 @@ func ParseObjectType(value string) (typ ObjectType, err error) {
 // The ObjectLookupIter must be closed with a call to Close() when it is no
 // longer needed.
 type ObjectLookupIter struct {
-	storage ObjectStorage
+	storage ObjectStorer
 	series  []Hash
 	t       ObjectType
 	pos     int
 }
 
 // NewObjectLookupIter returns an object iterator given an object storage and
 // a slice of object hashes.
-func NewObjectLookupIter(storage ObjectStorage, t ObjectType, series []Hash) *ObjectLookupIter {
+func NewObjectLookupIter(storage ObjectStorer, t ObjectType, series []Hash) *ObjectLookupIter {
 	return &ObjectLookupIter{
 		storage: storage,
 		series:  series,
@@ -142,7 +127,7 @@ func (iter *ObjectLookupIter) Next() (Object, error) {
 	}
 
 	hash := iter.series[iter.pos]
-	obj, err := iter.storage.Get(iter.t, hash)
+	obj, err := iter.storage.Object(iter.t, hash)
 	if err == nil {
 		iter.pos++
 	}

core/object_test.go

@@ -159,18 +159,18 @@ func (o *MockObjectStorage) NewObject() Object {
 	return nil
 }
 
-func (o *MockObjectStorage) Set(obj Object) (Hash, error) {
+func (o *MockObjectStorage) SetObject(obj Object) (Hash, error) {
 	return ZeroHash, nil
 }
 
-func (o *MockObjectStorage) Get(t ObjectType, h Hash) (Object, error) {
+func (o *MockObjectStorage) Object(t ObjectType, h Hash) (Object, error) {
 	return &MemoryObject{h: h}, nil
 }
 
-func (o *MockObjectStorage) Iter(t ObjectType) (ObjectIter, error) {
+func (o *MockObjectStorage) IterObjects(t ObjectType) (ObjectIter, error) {
 	return nil, nil
 }
 
-func (o *MockObjectStorage) Begin() TxObjectStorage {
+func (o *MockObjectStorage) Begin() Transaction {
 	return nil
 }

core/reference.go

@@ -203,15 +203,15 @@ func (iter *ReferenceSliceIter) Close() {
 	iter.pos = len(iter.series)
 }
 
-func ResolveReference(s ReferenceStorage, n ReferenceName) (*Reference, error) {
-	r, err := s.Get(n)
+func ResolveReference(s ReferenceStorer, n ReferenceName) (*Reference, error) {
+	r, err := s.Reference(n)
 	if err != nil || r == nil {
 		return r, err
 	}
 	return resolveReference(s, r, 0)
 }
 
-func resolveReference(s ReferenceStorage, r *Reference, recursion int) (*Reference, error) {
+func resolveReference(s ReferenceStorer, r *Reference, recursion int) (*Reference, error) {
 	if r.Type() != SymbolicReference {
 		return r, nil
 	}
@@ -220,7 +220,7 @@ func resolveReference(s ReferenceStorage, r *Reference, recursion int) (*Referen
 		return nil, ErrMaxResolveRecursion
 	}
 
-	t, err := s.Get(r.Target())
+	t, err := s.Reference(r.Target())
 	if err != nil {
 		return nil, err
 	}