aboutsummaryrefslogtreecommitdiffstats
path: root/storage/memory/storage.go
blob: 3d4e84a1ce1d3dba5ffd32328aef000dfd18eb24 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
// 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/plumbing"
	"gopkg.in/src-d/go-git.v4/plumbing/format/index"
	"gopkg.in/src-d/go-git.v4/plumbing/storer"
	"gopkg.in/src-d/go-git.v4/storage"
)

var ErrUnsupportedObjectType = fmt.Errorf("unsupported object type")
var ErrRefHasChanged = fmt.Errorf("reference has changed concurrently")

// 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
	ShallowStorage
	IndexStorage
	ReferenceStorage
	ModuleStorage
}

// NewStorage returns a new Storage base on memory
func NewStorage() *Storage {
	return &Storage{
		ReferenceStorage: make(ReferenceStorage),
		ConfigStorage:    ConfigStorage{},
		ShallowStorage:   ShallowStorage{},
		ObjectStorage: ObjectStorage{
			Objects: make(map[plumbing.Hash]plumbing.EncodedObject),
			Commits: make(map[plumbing.Hash]plumbing.EncodedObject),
			Trees:   make(map[plumbing.Hash]plumbing.EncodedObject),
			Blobs:   make(map[plumbing.Hash]plumbing.EncodedObject),
			Tags:    make(map[plumbing.Hash]plumbing.EncodedObject),
		},
		ModuleStorage: make(ModuleStorage),
	}
}

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 IndexStorage struct {
	index *index.Index
}

func (c *IndexStorage) SetIndex(idx *index.Index) error {
	c.index = idx
	return nil
}

func (c *IndexStorage) Index() (*index.Index, error) {
	if c.index == nil {
		c.index = &index.Index{Version: 2}
	}

	return c.index, nil
}

type ObjectStorage struct {
	Objects map[plumbing.Hash]plumbing.EncodedObject
	Commits map[plumbing.Hash]plumbing.EncodedObject
	Trees   map[plumbing.Hash]plumbing.EncodedObject
	Blobs   map[plumbing.Hash]plumbing.EncodedObject
	Tags    map[plumbing.Hash]plumbing.EncodedObject
}

func (o *ObjectStorage) NewEncodedObject() plumbing.EncodedObject {
	return &plumbing.MemoryObject{}
}

func (o *ObjectStorage) SetEncodedObject(obj plumbing.EncodedObject) (plumbing.Hash, error) {
	h := obj.Hash()
	o.Objects[h] = obj

	switch obj.Type() {
	case plumbing.CommitObject:
		o.Commits[h] = o.Objects[h]
	case plumbing.TreeObject:
		o.Trees[h] = o.Objects[h]
	case plumbing.BlobObject:
		o.Blobs[h] = o.Objects[h]
	case plumbing.TagObject:
		o.Tags[h] = o.Objects[h]
	default:
		return h, ErrUnsupportedObjectType
	}

	return h, nil
}

func (o *ObjectStorage) EncodedObject(t plumbing.ObjectType, h plumbing.Hash) (plumbing.EncodedObject, error) {
	obj, ok := o.Objects[h]
	if !ok || (plumbing.AnyObject != t && obj.Type() != t) {
		return nil, plumbing.ErrObjectNotFound
	}

	return obj, nil
}

func (o *ObjectStorage) IterEncodedObjects(t plumbing.ObjectType) (storer.EncodedObjectIter, error) {
	var series []plumbing.EncodedObject
	switch t {
	case plumbing.AnyObject:
		series = flattenObjectMap(o.Objects)
	case plumbing.CommitObject:
		series = flattenObjectMap(o.Commits)
	case plumbing.TreeObject:
		series = flattenObjectMap(o.Trees)
	case plumbing.BlobObject:
		series = flattenObjectMap(o.Blobs)
	case plumbing.TagObject:
		series = flattenObjectMap(o.Tags)
	}

	return storer.NewEncodedObjectSliceIter(series), nil
}

func flattenObjectMap(m map[plumbing.Hash]plumbing.EncodedObject) []plumbing.EncodedObject {
	objects := make([]plumbing.EncodedObject, 0, len(m))
	for _, obj := range m {
		objects = append(objects, obj)
	}
	return objects
}

func (o *ObjectStorage) Begin() storer.Transaction {
	return &TxObjectStorage{
		Storage: o,
		Objects: make(map[plumbing.Hash]plumbing.EncodedObject),
	}
}

type TxObjectStorage struct {
	Storage *ObjectStorage
	Objects map[plumbing.Hash]plumbing.EncodedObject
}

func (tx *TxObjectStorage) SetEncodedObject(obj plumbing.EncodedObject) (plumbing.Hash, error) {
	h := obj.Hash()
	tx.Objects[h] = obj

	return h, nil
}

func (tx *TxObjectStorage) EncodedObject(t plumbing.ObjectType, h plumbing.Hash) (plumbing.EncodedObject, error) {
	obj, ok := tx.Objects[h]
	if !ok || (plumbing.AnyObject != t && obj.Type() != t) {
		return nil, plumbing.ErrObjectNotFound
	}

	return obj, nil
}

func (tx *TxObjectStorage) Commit() error {
	for h, obj := range tx.Objects {
		delete(tx.Objects, h)
		if _, err := tx.Storage.SetEncodedObject(obj); err != nil {
			return err
		}
	}

	return nil
}

func (tx *TxObjectStorage) Rollback() error {
	tx.Objects = make(map[plumbing.Hash]plumbing.EncodedObject)
	return nil
}

type ReferenceStorage map[plumbing.ReferenceName]*plumbing.Reference

func (r ReferenceStorage) SetReference(ref *plumbing.Reference) error {
	if ref != nil {
		r[ref.Name()] = ref
	}

	return nil
}

func (r ReferenceStorage) CheckAndSetReference(ref, old *plumbing.Reference) error {
	if ref == nil {
		return nil
	}

	if old != nil {
		tmp := r[ref.Name()]
		if tmp != nil && tmp.Hash() != old.Hash() {
			return ErrRefHasChanged
		}
	}
	r[ref.Name()] = ref
	return nil
}

func (r ReferenceStorage) Reference(n plumbing.ReferenceName) (*plumbing.Reference, error) {
	ref, ok := r[n]
	if !ok {
		return nil, plumbing.ErrReferenceNotFound
	}

	return ref, nil
}

func (r ReferenceStorage) IterReferences() (storer.ReferenceIter, error) {
	var refs []*plumbing.Reference
	for _, ref := range r {
		refs = append(refs, ref)
	}

	return storer.NewReferenceSliceIter(refs), nil
}

func (r ReferenceStorage) CountLooseRefs() (int, error) {
	return len(r), nil
}

func (r ReferenceStorage) PackRefs() error {
	return nil
}

func (r ReferenceStorage) RemoveReference(n plumbing.ReferenceName) error {
	delete(r, n)
	return nil
}

type ShallowStorage []plumbing.Hash

func (s *ShallowStorage) SetShallow(commits []plumbing.Hash) error {
	*s = commits
	return nil
}

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 m, ok := s[name]; ok {
		return m, nil
	}

	m := NewStorage()
	s[name] = m

	return m, nil
}