git.go

  1// Package repository contains helper methods for working with the Git repo.
  2package repository
  3
  4import (
  5	"bytes"
  6	"fmt"
  7	"os"
  8	"path/filepath"
  9	"strings"
 10	"sync"
 11
 12	"github.com/blevesearch/bleve"
 13	"github.com/go-git/go-billy/v5"
 14	"github.com/go-git/go-billy/v5/osfs"
 15
 16	"github.com/MichaelMure/git-bug/util/lamport"
 17)
 18
 19const (
 20	clockPath = "git-bug"
 21)
 22
 23var _ ClockedRepo = &GitRepo{}
 24var _ TestedRepo = &GitRepo{}
 25
 26// GitRepo represents an instance of a (local) git repository.
 27type GitRepo struct {
 28	gitCli
 29	path string
 30
 31	clocksMutex sync.Mutex
 32	clocks      map[string]lamport.Clock
 33
 34	indexesMutex sync.Mutex
 35	indexes      map[string]bleve.Index
 36
 37	keyring Keyring
 38}
 39
 40// OpenGitRepo determines if the given working directory is inside of a git repository,
 41// and returns the corresponding GitRepo instance if it is.
 42func OpenGitRepo(path string, clockLoaders []ClockLoader) (*GitRepo, error) {
 43	k, err := defaultKeyring()
 44	if err != nil {
 45		return nil, err
 46	}
 47
 48	repo := &GitRepo{
 49		gitCli:  gitCli{path: path},
 50		path:    path,
 51		clocks:  make(map[string]lamport.Clock),
 52		indexes: make(map[string]bleve.Index),
 53		keyring: k,
 54	}
 55
 56	// Check the repo and retrieve the root path
 57	stdout, err := repo.runGitCommand("rev-parse", "--absolute-git-dir")
 58
 59	// Now dir is fetched with "git rev-parse --git-dir". May be it can
 60	// still return nothing in some cases. Then empty stdout check is
 61	// kept.
 62	if err != nil || stdout == "" {
 63		return nil, ErrNotARepo
 64	}
 65
 66	// Fix the path to be sure we are at the root
 67	repo.path = stdout
 68	repo.gitCli.path = stdout
 69
 70	for _, loader := range clockLoaders {
 71		allExist := true
 72		for _, name := range loader.Clocks {
 73			if _, err := repo.getClock(name); err != nil {
 74				allExist = false
 75			}
 76		}
 77
 78		if !allExist {
 79			err = loader.Witnesser(repo)
 80			if err != nil {
 81				return nil, err
 82			}
 83		}
 84	}
 85
 86	return repo, nil
 87}
 88
 89// InitGitRepo create a new empty git repo at the given path
 90func InitGitRepo(path string) (*GitRepo, error) {
 91	repo := &GitRepo{
 92		gitCli:  gitCli{path: path},
 93		path:    path + "/.git",
 94		clocks:  make(map[string]lamport.Clock),
 95		indexes: make(map[string]bleve.Index),
 96	}
 97
 98	_, err := repo.runGitCommand("init", path)
 99	if err != nil {
100		return nil, err
101	}
102
103	return repo, nil
104}
105
106// InitBareGitRepo create a new --bare empty git repo at the given path
107func InitBareGitRepo(path string) (*GitRepo, error) {
108	repo := &GitRepo{
109		gitCli:  gitCli{path: path},
110		path:    path,
111		clocks:  make(map[string]lamport.Clock),
112		indexes: make(map[string]bleve.Index),
113	}
114
115	_, err := repo.runGitCommand("init", "--bare", path)
116	if err != nil {
117		return nil, err
118	}
119
120	return repo, nil
121}
122
123func (repo *GitRepo) Close() error {
124	var firstErr error
125	for _, index := range repo.indexes {
126		err := index.Close()
127		if err != nil && firstErr == nil {
128			firstErr = err
129		}
130	}
131	return firstErr
132}
133
134// LocalConfig give access to the repository scoped configuration
135func (repo *GitRepo) LocalConfig() Config {
136	return newGitConfig(repo.gitCli, false)
137}
138
139// GlobalConfig give access to the global scoped configuration
140func (repo *GitRepo) GlobalConfig() Config {
141	return newGitConfig(repo.gitCli, true)
142}
143
144// AnyConfig give access to a merged local/global configuration
145func (repo *GitRepo) AnyConfig() ConfigRead {
146	return mergeConfig(repo.LocalConfig(), repo.GlobalConfig())
147}
148
149// Keyring give access to a user-wide storage for secrets
150func (repo *GitRepo) Keyring() Keyring {
151	return repo.keyring
152}
153
154// GetPath returns the path to the repo.
155func (repo *GitRepo) GetPath() string {
156	return repo.path
157}
158
159// GetUserName returns the name the the user has used to configure git
160func (repo *GitRepo) GetUserName() (string, error) {
161	return repo.runGitCommand("config", "user.name")
162}
163
164// GetUserEmail returns the email address that the user has used to configure git.
165func (repo *GitRepo) GetUserEmail() (string, error) {
166	return repo.runGitCommand("config", "user.email")
167}
168
169// GetCoreEditor returns the name of the editor that the user has used to configure git.
170func (repo *GitRepo) GetCoreEditor() (string, error) {
171	return repo.runGitCommand("var", "GIT_EDITOR")
172}
173
174// GetRemotes returns the configured remotes repositories.
175func (repo *GitRepo) GetRemotes() (map[string]string, error) {
176	stdout, err := repo.runGitCommand("remote", "--verbose")
177	if err != nil {
178		return nil, err
179	}
180
181	lines := strings.Split(stdout, "\n")
182	remotes := make(map[string]string, len(lines))
183
184	for _, line := range lines {
185		if strings.TrimSpace(line) == "" {
186			continue
187		}
188		elements := strings.Fields(line)
189		if len(elements) != 3 {
190			return nil, fmt.Errorf("git remote: unexpected output format: %s", line)
191		}
192
193		remotes[elements[0]] = elements[1]
194	}
195
196	return remotes, nil
197}
198
199// LocalStorage return a billy.Filesystem giving access to $RepoPath/.git/git-bug
200func (repo *GitRepo) LocalStorage() billy.Filesystem {
201	return osfs.New(repo.path)
202}
203
204// GetBleveIndex return a bleve.Index that can be used to index documents
205func (repo *GitRepo) GetBleveIndex(name string) (bleve.Index, error) {
206	repo.indexesMutex.Lock()
207	defer repo.indexesMutex.Unlock()
208
209	if index, ok := repo.indexes[name]; ok {
210		return index, nil
211	}
212
213	path := filepath.Join(repo.path, "indexes", name)
214
215	index, err := bleve.Open(path)
216	if err == nil {
217		repo.indexes[name] = index
218		return index, nil
219	}
220
221	err = os.MkdirAll(path, os.ModeDir)
222	if err != nil {
223		return nil, err
224	}
225
226	mapping := bleve.NewIndexMapping()
227	mapping.DefaultAnalyzer = "en"
228
229	index, err = bleve.New(path, mapping)
230	if err != nil {
231		return nil, err
232	}
233
234	repo.indexes[name] = index
235
236	return index, nil
237}
238
239// ClearBleveIndex will wipe the given index
240func (repo *GitRepo) ClearBleveIndex(name string) error {
241	repo.indexesMutex.Lock()
242	defer repo.indexesMutex.Unlock()
243
244	path := filepath.Join(repo.path, "indexes", name)
245
246	err := os.RemoveAll(path)
247	if err != nil {
248		return err
249	}
250
251	delete(repo.indexes, name)
252
253	return nil
254}
255
256// FetchRefs fetch git refs from a remote
257func (repo *GitRepo) FetchRefs(remote, refSpec string) (string, error) {
258	stdout, err := repo.runGitCommand("fetch", remote, refSpec)
259
260	if err != nil {
261		return stdout, fmt.Errorf("failed to fetch from the remote '%s': %v", remote, err)
262	}
263
264	return stdout, err
265}
266
267// PushRefs push git refs to a remote
268func (repo *GitRepo) PushRefs(remote string, refSpec string) (string, error) {
269	stdout, stderr, err := repo.runGitCommandRaw(nil, "push", remote, refSpec)
270
271	if err != nil {
272		return stdout + stderr, fmt.Errorf("failed to push to the remote '%s': %v", remote, stderr)
273	}
274	return stdout + stderr, nil
275}
276
277// StoreData will store arbitrary data and return the corresponding hash
278func (repo *GitRepo) StoreData(data []byte) (Hash, error) {
279	var stdin = bytes.NewReader(data)
280
281	stdout, err := repo.runGitCommandWithStdin(stdin, "hash-object", "--stdin", "-w")
282
283	return Hash(stdout), err
284}
285
286// ReadData will attempt to read arbitrary data from the given hash
287func (repo *GitRepo) ReadData(hash Hash) ([]byte, error) {
288	var stdout bytes.Buffer
289	var stderr bytes.Buffer
290
291	err := repo.runGitCommandWithIO(nil, &stdout, &stderr, "cat-file", "-p", string(hash))
292
293	if err != nil {
294		return []byte{}, err
295	}
296
297	return stdout.Bytes(), nil
298}
299
300// StoreTree will store a mapping key-->Hash as a Git tree
301func (repo *GitRepo) StoreTree(entries []TreeEntry) (Hash, error) {
302	buffer := prepareTreeEntries(entries)
303
304	stdout, err := repo.runGitCommandWithStdin(&buffer, "mktree")
305
306	if err != nil {
307		return "", err
308	}
309
310	return Hash(stdout), nil
311}
312
313// StoreCommit will store a Git commit with the given Git tree
314func (repo *GitRepo) StoreCommit(treeHash Hash) (Hash, error) {
315	stdout, err := repo.runGitCommand("commit-tree", string(treeHash))
316
317	if err != nil {
318		return "", err
319	}
320
321	return Hash(stdout), nil
322}
323
324// StoreCommitWithParent will store a Git commit with the given Git tree
325func (repo *GitRepo) StoreCommitWithParent(treeHash Hash, parent Hash) (Hash, error) {
326	stdout, err := repo.runGitCommand("commit-tree", string(treeHash),
327		"-p", string(parent))
328
329	if err != nil {
330		return "", err
331	}
332
333	return Hash(stdout), nil
334}
335
336// UpdateRef will create or update a Git reference
337func (repo *GitRepo) UpdateRef(ref string, hash Hash) error {
338	_, err := repo.runGitCommand("update-ref", ref, string(hash))
339
340	return err
341}
342
343// RemoveRef will remove a Git reference
344func (repo *GitRepo) RemoveRef(ref string) error {
345	_, err := repo.runGitCommand("update-ref", "-d", ref)
346
347	return err
348}
349
350// ListRefs will return a list of Git ref matching the given refspec
351func (repo *GitRepo) ListRefs(refPrefix string) ([]string, error) {
352	stdout, err := repo.runGitCommand("for-each-ref", "--format=%(refname)", refPrefix)
353
354	if err != nil {
355		return nil, err
356	}
357
358	split := strings.Split(stdout, "\n")
359
360	if len(split) == 1 && split[0] == "" {
361		return []string{}, nil
362	}
363
364	return split, nil
365}
366
367// RefExist will check if a reference exist in Git
368func (repo *GitRepo) RefExist(ref string) (bool, error) {
369	stdout, err := repo.runGitCommand("for-each-ref", ref)
370
371	if err != nil {
372		return false, err
373	}
374
375	return stdout != "", nil
376}
377
378// CopyRef will create a new reference with the same value as another one
379func (repo *GitRepo) CopyRef(source string, dest string) error {
380	_, err := repo.runGitCommand("update-ref", dest, source)
381
382	return err
383}
384
385// ListCommits will return the list of commit hashes of a ref, in chronological order
386func (repo *GitRepo) ListCommits(ref string) ([]Hash, error) {
387	stdout, err := repo.runGitCommand("rev-list", "--first-parent", "--reverse", ref)
388
389	if err != nil {
390		return nil, err
391	}
392
393	split := strings.Split(stdout, "\n")
394
395	casted := make([]Hash, len(split))
396	for i, line := range split {
397		casted[i] = Hash(line)
398	}
399
400	return casted, nil
401
402}
403
404// ReadTree will return the list of entries in a Git tree
405func (repo *GitRepo) ReadTree(hash Hash) ([]TreeEntry, error) {
406	stdout, err := repo.runGitCommand("ls-tree", string(hash))
407
408	if err != nil {
409		return nil, err
410	}
411
412	return readTreeEntries(stdout)
413}
414
415// FindCommonAncestor will return the last common ancestor of two chain of commit
416func (repo *GitRepo) FindCommonAncestor(hash1 Hash, hash2 Hash) (Hash, error) {
417	stdout, err := repo.runGitCommand("merge-base", string(hash1), string(hash2))
418
419	if err != nil {
420		return "", err
421	}
422
423	return Hash(stdout), nil
424}
425
426// GetTreeHash return the git tree hash referenced in a commit
427func (repo *GitRepo) GetTreeHash(commit Hash) (Hash, error) {
428	stdout, err := repo.runGitCommand("rev-parse", string(commit)+"^{tree}")
429
430	if err != nil {
431		return "", err
432	}
433
434	return Hash(stdout), nil
435}
436
437// GetOrCreateClock return a Lamport clock stored in the Repo.
438// If the clock doesn't exist, it's created.
439func (repo *GitRepo) GetOrCreateClock(name string) (lamport.Clock, error) {
440	repo.clocksMutex.Lock()
441	defer repo.clocksMutex.Unlock()
442
443	c, err := repo.getClock(name)
444	if err == nil {
445		return c, nil
446	}
447	if err != ErrClockNotExist {
448		return nil, err
449	}
450
451	c, err = lamport.NewPersistedClock(repo.LocalStorage(), name+"-clock")
452	if err != nil {
453		return nil, err
454	}
455
456	repo.clocks[name] = c
457	return c, nil
458}
459
460func (repo *GitRepo) getClock(name string) (lamport.Clock, error) {
461	if c, ok := repo.clocks[name]; ok {
462		return c, nil
463	}
464
465	c, err := lamport.LoadPersistedClock(repo.LocalStorage(), name+"-clock")
466	if err == nil {
467		repo.clocks[name] = c
468		return c, nil
469	}
470	if err == lamport.ErrClockNotExist {
471		return nil, ErrClockNotExist
472	}
473	return nil, err
474}
475
476// AddRemote add a new remote to the repository
477// Not in the interface because it's only used for testing
478func (repo *GitRepo) AddRemote(name string, url string) error {
479	_, err := repo.runGitCommand("remote", "add", name, url)
480
481	return err
482}
483
484// GetLocalRemote return the URL to use to add this repo as a local remote
485func (repo *GitRepo) GetLocalRemote() string {
486	return repo.path
487}
488
489// EraseFromDisk delete this repository entirely from the disk
490func (repo *GitRepo) EraseFromDisk() error {
491	err := repo.Close()
492	if err != nil {
493		return err
494	}
495
496	path := filepath.Clean(strings.TrimSuffix(repo.path, string(filepath.Separator)+".git"))
497
498	// fmt.Println("Cleaning repo:", path)
499	return os.RemoveAll(path)
500}