1// Package repository contains helper methods for working with the Git repo.
2package repository
3
4import (
5 "bytes"
6 "fmt"
7 "io"
8 "os/exec"
9 "path"
10 "strings"
11
12 "github.com/pkg/errors"
13
14 "github.com/MichaelMure/git-bug/util/git"
15 "github.com/MichaelMure/git-bug/util/lamport"
16)
17
18const (
19 createClockFile = "/git-bug/create-clock"
20 editClockFile = "/git-bug/edit-clock"
21)
22
23var (
24 // ErrNotARepo is the error returned when the git repo root wan't be found
25 ErrNotARepo = errors.New("not a git repository")
26)
27
28var _ ClockedRepo = &GitRepo{}
29
30// GitRepo represents an instance of a (local) git repository.
31type GitRepo struct {
32 Path string
33 createClock *lamport.Persisted
34 editClock *lamport.Persisted
35}
36
37// LocalConfig give access to the repository scoped configuration
38func (repo *GitRepo) LocalConfig() Config {
39 return newGitConfig(repo, false)
40}
41
42// GlobalConfig give access to the git global configuration
43func (repo *GitRepo) GlobalConfig() Config {
44 return newGitConfig(repo, true)
45}
46
47// Run the given git command with the given I/O reader/writers, returning an error if it fails.
48func (repo *GitRepo) runGitCommandWithIO(stdin io.Reader, stdout, stderr io.Writer, args ...string) error {
49 repopath := repo.Path
50 if repopath == ".git" {
51 // seeduvax> trangely the git command sometimes fail for very unknown
52 // reason wihtout this replacement.
53 // observed with rev-list command when git-bug is called from git
54 // hook script, even the same command with same args runs perfectly
55 // when called directly from the same hook script.
56 repopath = ""
57 }
58 // fmt.Printf("[%s] Running git %s\n", repopath, strings.Join(args, " "))
59
60 cmd := exec.Command("git", args...)
61 cmd.Dir = repopath
62 cmd.Stdin = stdin
63 cmd.Stdout = stdout
64 cmd.Stderr = stderr
65
66 return cmd.Run()
67}
68
69// Run the given git command and return its stdout, or an error if the command fails.
70func (repo *GitRepo) runGitCommandRaw(stdin io.Reader, args ...string) (string, string, error) {
71 var stdout bytes.Buffer
72 var stderr bytes.Buffer
73 err := repo.runGitCommandWithIO(stdin, &stdout, &stderr, args...)
74 return strings.TrimSpace(stdout.String()), strings.TrimSpace(stderr.String()), err
75}
76
77// Run the given git command and return its stdout, or an error if the command fails.
78func (repo *GitRepo) runGitCommandWithStdin(stdin io.Reader, args ...string) (string, error) {
79 stdout, stderr, err := repo.runGitCommandRaw(stdin, args...)
80 if err != nil {
81 if stderr == "" {
82 stderr = "Error running git command: " + strings.Join(args, " ")
83 }
84 err = fmt.Errorf(stderr)
85 }
86 return stdout, err
87}
88
89// Run the given git command and return its stdout, or an error if the command fails.
90func (repo *GitRepo) runGitCommand(args ...string) (string, error) {
91 return repo.runGitCommandWithStdin(nil, args...)
92}
93
94// NewGitRepo determines if the given working directory is inside of a git repository,
95// and returns the corresponding GitRepo instance if it is.
96func NewGitRepo(path string, witnesser Witnesser) (*GitRepo, error) {
97 repo := &GitRepo{Path: path}
98
99 // Check the repo and retrieve the root path
100 stdout, err := repo.runGitCommand("rev-parse", "--git-dir")
101
102 // Now dir is fetched with "git rev-parse --git-dir". May be it can
103 // still return nothing in some cases. Then empty stdout check is
104 // kept.
105 if err != nil || stdout == "" {
106 return nil, ErrNotARepo
107 }
108
109 // Fix the path to be sure we are at the root
110 repo.Path = stdout
111
112 err = repo.LoadClocks()
113
114 if err != nil {
115 // No clock yet, trying to initialize them
116 err = repo.createClocks()
117 if err != nil {
118 return nil, err
119 }
120
121 err = witnesser(repo)
122 if err != nil {
123 return nil, err
124 }
125
126 err = repo.WriteClocks()
127 if err != nil {
128 return nil, err
129 }
130
131 return repo, nil
132 }
133
134 return repo, nil
135}
136
137// InitGitRepo create a new empty git repo at the given path
138func InitGitRepo(path string) (*GitRepo, error) {
139 repo := &GitRepo{Path: path + "/.git"}
140 err := repo.createClocks()
141 if err != nil {
142 return nil, err
143 }
144
145 _, err = repo.runGitCommand("init", path)
146 if err != nil {
147 return nil, err
148 }
149
150 return repo, nil
151}
152
153// InitBareGitRepo create a new --bare empty git repo at the given path
154func InitBareGitRepo(path string) (*GitRepo, error) {
155 repo := &GitRepo{Path: path}
156 err := repo.createClocks()
157 if err != nil {
158 return nil, err
159 }
160
161 _, err = repo.runGitCommand("init", "--bare", path)
162 if err != nil {
163 return nil, err
164 }
165
166 return repo, nil
167}
168
169// GetPath returns the path to the repo.
170func (repo *GitRepo) GetPath() string {
171 return repo.Path
172}
173
174// GetUserName returns the name the the user has used to configure git
175func (repo *GitRepo) GetUserName() (string, error) {
176 return repo.runGitCommand("config", "user.name")
177}
178
179// GetUserEmail returns the email address that the user has used to configure git.
180func (repo *GitRepo) GetUserEmail() (string, error) {
181 return repo.runGitCommand("config", "user.email")
182}
183
184// GetCoreEditor returns the name of the editor that the user has used to configure git.
185func (repo *GitRepo) GetCoreEditor() (string, error) {
186 return repo.runGitCommand("var", "GIT_EDITOR")
187}
188
189// GetRemotes returns the configured remotes repositories.
190func (repo *GitRepo) GetRemotes() (map[string]string, error) {
191 stdout, err := repo.runGitCommand("remote", "--verbose")
192 if err != nil {
193 return nil, err
194 }
195
196 lines := strings.Split(stdout, "\n")
197 remotes := make(map[string]string, len(lines))
198
199 for _, line := range lines {
200 if strings.TrimSpace(line) == "" {
201 continue
202 }
203 elements := strings.Fields(line)
204 if len(elements) != 3 {
205 return nil, fmt.Errorf("git remote: unexpected output format: %s", line)
206 }
207
208 remotes[elements[0]] = elements[1]
209 }
210
211 return remotes, nil
212}
213
214// FetchRefs fetch git refs from a remote
215func (repo *GitRepo) FetchRefs(remote, refSpec string) (string, error) {
216 stdout, err := repo.runGitCommand("fetch", remote, refSpec)
217
218 if err != nil {
219 return stdout, fmt.Errorf("failed to fetch from the remote '%s': %v", remote, err)
220 }
221
222 return stdout, err
223}
224
225// PushRefs push git refs to a remote
226func (repo *GitRepo) PushRefs(remote string, refSpec string) (string, error) {
227 stdout, stderr, err := repo.runGitCommandRaw(nil, "push", remote, refSpec)
228
229 if err != nil {
230 return stdout + stderr, fmt.Errorf("failed to push to the remote '%s': %v", remote, stderr)
231 }
232 return stdout + stderr, nil
233}
234
235// StoreData will store arbitrary data and return the corresponding hash
236func (repo *GitRepo) StoreData(data []byte) (git.Hash, error) {
237 var stdin = bytes.NewReader(data)
238
239 stdout, err := repo.runGitCommandWithStdin(stdin, "hash-object", "--stdin", "-w")
240
241 return git.Hash(stdout), err
242}
243
244// ReadData will attempt to read arbitrary data from the given hash
245func (repo *GitRepo) ReadData(hash git.Hash) ([]byte, error) {
246 var stdout bytes.Buffer
247 var stderr bytes.Buffer
248
249 err := repo.runGitCommandWithIO(nil, &stdout, &stderr, "cat-file", "-p", string(hash))
250
251 if err != nil {
252 return []byte{}, err
253 }
254
255 return stdout.Bytes(), nil
256}
257
258// StoreTree will store a mapping key-->Hash as a Git tree
259func (repo *GitRepo) StoreTree(entries []TreeEntry) (git.Hash, error) {
260 buffer := prepareTreeEntries(entries)
261
262 stdout, err := repo.runGitCommandWithStdin(&buffer, "mktree")
263
264 if err != nil {
265 return "", err
266 }
267
268 return git.Hash(stdout), nil
269}
270
271// StoreCommit will store a Git commit with the given Git tree
272func (repo *GitRepo) StoreCommit(treeHash git.Hash) (git.Hash, error) {
273 stdout, err := repo.runGitCommand("commit-tree", string(treeHash))
274
275 if err != nil {
276 return "", err
277 }
278
279 return git.Hash(stdout), nil
280}
281
282// StoreCommitWithParent will store a Git commit with the given Git tree
283func (repo *GitRepo) StoreCommitWithParent(treeHash git.Hash, parent git.Hash) (git.Hash, error) {
284 stdout, err := repo.runGitCommand("commit-tree", string(treeHash),
285 "-p", string(parent))
286
287 if err != nil {
288 return "", err
289 }
290
291 return git.Hash(stdout), nil
292}
293
294// UpdateRef will create or update a Git reference
295func (repo *GitRepo) UpdateRef(ref string, hash git.Hash) error {
296 _, err := repo.runGitCommand("update-ref", ref, string(hash))
297
298 return err
299}
300
301// ListRefs will return a list of Git ref matching the given refspec
302func (repo *GitRepo) ListRefs(refspec string) ([]string, error) {
303 stdout, err := repo.runGitCommand("for-each-ref", "--format=%(refname)", refspec)
304
305 if err != nil {
306 return nil, err
307 }
308
309 split := strings.Split(stdout, "\n")
310
311 if len(split) == 1 && split[0] == "" {
312 return []string{}, nil
313 }
314
315 return split, nil
316}
317
318// RefExist will check if a reference exist in Git
319func (repo *GitRepo) RefExist(ref string) (bool, error) {
320 stdout, err := repo.runGitCommand("for-each-ref", ref)
321
322 if err != nil {
323 return false, err
324 }
325
326 return stdout != "", nil
327}
328
329// CopyRef will create a new reference with the same value as another one
330func (repo *GitRepo) CopyRef(source string, dest string) error {
331 _, err := repo.runGitCommand("update-ref", dest, source)
332
333 return err
334}
335
336// ListCommits will return the list of commit hashes of a ref, in chronological order
337func (repo *GitRepo) ListCommits(ref string) ([]git.Hash, error) {
338 stdout, err := repo.runGitCommand("rev-list", "--first-parent", "--reverse", ref)
339
340 if err != nil {
341 return nil, err
342 }
343
344 split := strings.Split(stdout, "\n")
345
346 casted := make([]git.Hash, len(split))
347 for i, line := range split {
348 casted[i] = git.Hash(line)
349 }
350
351 return casted, nil
352
353}
354
355// ListEntries will return the list of entries in a Git tree
356func (repo *GitRepo) ListEntries(hash git.Hash) ([]TreeEntry, error) {
357 stdout, err := repo.runGitCommand("ls-tree", string(hash))
358
359 if err != nil {
360 return nil, err
361 }
362
363 return readTreeEntries(stdout)
364}
365
366// FindCommonAncestor will return the last common ancestor of two chain of commit
367func (repo *GitRepo) FindCommonAncestor(hash1 git.Hash, hash2 git.Hash) (git.Hash, error) {
368 stdout, err := repo.runGitCommand("merge-base", string(hash1), string(hash2))
369
370 if err != nil {
371 return "", err
372 }
373
374 return git.Hash(stdout), nil
375}
376
377// GetTreeHash return the git tree hash referenced in a commit
378func (repo *GitRepo) GetTreeHash(commit git.Hash) (git.Hash, error) {
379 stdout, err := repo.runGitCommand("rev-parse", string(commit)+"^{tree}")
380
381 if err != nil {
382 return "", err
383 }
384
385 return git.Hash(stdout), nil
386}
387
388// AddRemote add a new remote to the repository
389// Not in the interface because it's only used for testing
390func (repo *GitRepo) AddRemote(name string, url string) error {
391 _, err := repo.runGitCommand("remote", "add", name, url)
392
393 return err
394}
395
396func (repo *GitRepo) createClocks() error {
397 createPath := path.Join(repo.Path, createClockFile)
398 createClock, err := lamport.NewPersisted(createPath)
399 if err != nil {
400 return err
401 }
402
403 editPath := path.Join(repo.Path, editClockFile)
404 editClock, err := lamport.NewPersisted(editPath)
405 if err != nil {
406 return err
407 }
408
409 repo.createClock = createClock
410 repo.editClock = editClock
411
412 return nil
413}
414
415// LoadClocks read the clocks values from the on-disk repo
416func (repo *GitRepo) LoadClocks() error {
417 createClock, err := lamport.LoadPersisted(repo.GetPath() + createClockFile)
418 if err != nil {
419 return err
420 }
421
422 editClock, err := lamport.LoadPersisted(repo.GetPath() + editClockFile)
423 if err != nil {
424 return err
425 }
426
427 repo.createClock = createClock
428 repo.editClock = editClock
429 return nil
430}
431
432// WriteClocks write the clocks values into the repo
433func (repo *GitRepo) WriteClocks() error {
434 err := repo.createClock.Write()
435 if err != nil {
436 return err
437 }
438
439 err = repo.editClock.Write()
440 if err != nil {
441 return err
442 }
443
444 return nil
445}
446
447// CreateTime return the current value of the creation clock
448func (repo *GitRepo) CreateTime() lamport.Time {
449 return repo.createClock.Time()
450}
451
452// CreateTimeIncrement increment the creation clock and return the new value.
453func (repo *GitRepo) CreateTimeIncrement() (lamport.Time, error) {
454 return repo.createClock.Increment()
455}
456
457// EditTime return the current value of the edit clock
458func (repo *GitRepo) EditTime() lamport.Time {
459 return repo.editClock.Time()
460}
461
462// EditTimeIncrement increment the edit clock and return the new value.
463func (repo *GitRepo) EditTimeIncrement() (lamport.Time, error) {
464 return repo.editClock.Increment()
465}
466
467// WitnessCreate witness another create time and increment the corresponding clock
468// if needed.
469func (repo *GitRepo) WitnessCreate(time lamport.Time) error {
470 return repo.createClock.Witness(time)
471}
472
473// WitnessEdit witness another edition time and increment the corresponding clock
474// if needed.
475func (repo *GitRepo) WitnessEdit(time lamport.Time) error {
476 return repo.editClock.Witness(time)
477}