// Package memory is a storage backend base on memory
package memory
import (
"fmt"
"gopkg.in/src-d/go-git.v4/config"
"gopkg.in/src-d/go-git.v4/core"
)
var ErrUnsupportedObjectType = fmt.Errorf("unsupported object type")
// Storage is an implementation of git.Storer that stores data on memory, being
// ephemeral. The use of this storage should be done in controlled envoriments,
// since the representation in memory of some repository can fill the machine
// memory. in the other hand this storage has the best performance.
type Storage struct {
ConfigStorage
ObjectStorage
ReferenceStorage
}
// NewStorage returns a new Storage base on memory
func NewStorage() *Storage {
return &Storage{
ReferenceStorage: make(ReferenceStorage, 0),
ConfigStorage: ConfigStorage{},
ObjectStorage: ObjectStorage{
Objects: make(map[core.Hash]core.Object, 0),
Commits: make(map[core.Hash]core.Object, 0),
Trees: make(map[core.Hash]core.Object, 0),
Blobs: make(map[core.Hash]core.Object, 0),
Tags: make(map[core.Hash]core.Object, 0),
},
}
}
type ConfigStorage struct {
config *config.Config
}
func (c *ConfigStorage) SetConfig(cfg *config.Config) error {
if err := cfg.Validate(); err != nil {
return err
}
c.config = cfg
return nil
}
func (c *ConfigStorage) Config() (*config.Config, error) {
if c.config == nil {
c.config = config.NewConfig()
}
return c.config, nil
}
type ObjectStorage struct {
Objects map[core.Hash]core.Object
Commits map[core.Hash]core.Object
Trees map[core.Hash]core.Object
Blobs map[core.Hash]core.Object
Tags map[core.Hash]core.Object
}
func (o *ObjectStorage) NewObject() core.Object {
return &core.MemoryObject{}
}
func (o *ObjectStorage) SetObject(obj core.Object) (core.Hash, error) {
h := obj.Hash()
o.Objects[h] = obj
switch obj.Type() {
case core.CommitObject:
o.Commits[h] = o.Objects[h]
case core.TreeObject:
o.Trees[h] = o.Objects[h]
case core.BlobObject:
o.Blobs[h] = o.Objects[h]
case core.TagObject:
o.Tags[h] = o.Objects[h]
default:
return h, ErrUnsupportedObjectType
}
return h, nil
}
func (o *ObjectStorage) Object(t core.ObjectType, h core.Hash) (core.Object, error) {
obj, ok := o.Objects[h]
if !ok || (core.AnyObject != t && obj.Type() != t) {
return nil, core.ErrObjectNotFound
}
return obj, nil
}
func (o *ObjectStorage) IterObjects(t core.ObjectType) (core.ObjectIter, error) {
var series []core.Object
switch t {
case core.AnyObject:
series = flattenObjectMap(o.Objects)
case core.CommitObject:
series = flattenObjectMap(o.Commits)
case core.TreeObject:
series = flattenObjectMap(o.Trees)
case core.BlobObject:
series = flattenObjectMap(o.Blobs)
case core.TagObject:
series = flattenObjectMap(o.Tags)
}
return core.NewObjectSliceIter(series), nil
}
func flattenObjectMap(m map[core.Hash]core.Object) []core.Object {
objects := make([]core.Object, 0, len(m))
for _, obj := range m {
objects = append(objects, obj)
}
return objects
}
func (o *ObjectStorage) Begin() core.Transaction {
return &TxObjectStorage{
Storage: o,
Objects: make(map[core.Hash]core.Object, 0),
}
}
type TxObjectStorage struct {
Storage *ObjectStorage
Objects map[core.Hash]core.Object
}
func (tx *TxObjectStorage) SetObject(obj core.Object) (core.Hash, error) {
h := obj.Hash()
tx.Objects[h] = obj
return h, nil
}
func (tx *TxObjectStorage) Object(t core.ObjectType, h core.Hash) (core.Object, error) {
obj, ok := tx.Objects[h]
if !ok || (core.AnyObject != t && obj.Type() != t) {
return nil, core.ErrObjectNotFound
}
return obj, nil
}
func (tx *TxObjectStorage) Commit() error {
for h, obj := range tx.Objects {
delete(tx.Objects, h)
if _, err := tx.Storage.SetObject(obj); err != nil {
return err
}
}
return nil
}
func (tx *TxObjectStorage) Rollback() error {
tx.Objects = make(map[core.Hash]core.Object, 0)
return nil
}
type ReferenceStorage map[core.ReferenceName]*core.Reference
func (r ReferenceStorage) SetReference(ref *core.Reference) error {
if ref != nil {
r[ref.Name()] = ref
}
return nil
}
func (r ReferenceStorage) Reference(n core.ReferenceName) (*core.Reference, error) {
ref, ok := r[n]
if !ok {
return nil, core.ErrReferenceNotFound
}
return ref, nil
}
func (r ReferenceStorage) IterReferences() (core.ReferenceIter, error) {
var refs []*core.Reference
for _, ref := range r {
refs = append(refs, ref)
}
return core.NewReferenceSliceIter(refs), nil
}
