forked from
tangled.org/core
Monorepo for Tangled — https://tangled.org
1package git
2
3import (
4 "archive/tar"
5 "bytes"
6 "fmt"
7 "io"
8 "io/fs"
9 "os/exec"
10 "path"
11 "sort"
12 "strconv"
13 "strings"
14 "sync"
15 "time"
16
17 "github.com/dgraph-io/ristretto"
18 "github.com/go-git/go-git/v5"
19 "github.com/go-git/go-git/v5/plumbing"
20 "github.com/go-git/go-git/v5/plumbing/object"
21 "tangled.sh/tangled.sh/core/types"
22)
23
24var (
25 commitCache *ristretto.Cache
26 cacheMu sync.RWMutex
27)
28
29func init() {
30 cache, _ := ristretto.NewCache(&ristretto.Config{
31 NumCounters: 1e7,
32 MaxCost: 1 << 30,
33 BufferItems: 64,
34 TtlTickerDurationInSec: 120,
35 })
36 commitCache = cache
37}
38
39var (
40 ErrBinaryFile = fmt.Errorf("binary file")
41 ErrNotBinaryFile = fmt.Errorf("not binary file")
42)
43
44type GitRepo struct {
45 path string
46 r *git.Repository
47 h plumbing.Hash
48}
49
50type TagList struct {
51 refs []*TagReference
52 r *git.Repository
53}
54
55// TagReference is used to list both tag and non-annotated tags.
56// Non-annotated tags should only contains a reference.
57// Annotated tags should contain its reference and its tag information.
58type TagReference struct {
59 ref *plumbing.Reference
60 tag *object.Tag
61}
62
63// infoWrapper wraps the property of a TreeEntry so it can export fs.FileInfo
64// to tar WriteHeader
65type infoWrapper struct {
66 name string
67 size int64
68 mode fs.FileMode
69 modTime time.Time
70 isDir bool
71}
72
73func (self *TagList) Len() int {
74 return len(self.refs)
75}
76
77func (self *TagList) Swap(i, j int) {
78 self.refs[i], self.refs[j] = self.refs[j], self.refs[i]
79}
80
81// sorting tags in reverse chronological order
82func (self *TagList) Less(i, j int) bool {
83 var dateI time.Time
84 var dateJ time.Time
85
86 if self.refs[i].tag != nil {
87 dateI = self.refs[i].tag.Tagger.When
88 } else {
89 c, err := self.r.CommitObject(self.refs[i].ref.Hash())
90 if err != nil {
91 dateI = time.Now()
92 } else {
93 dateI = c.Committer.When
94 }
95 }
96
97 if self.refs[j].tag != nil {
98 dateJ = self.refs[j].tag.Tagger.When
99 } else {
100 c, err := self.r.CommitObject(self.refs[j].ref.Hash())
101 if err != nil {
102 dateJ = time.Now()
103 } else {
104 dateJ = c.Committer.When
105 }
106 }
107
108 return dateI.After(dateJ)
109}
110
111func Open(path string, ref string) (*GitRepo, error) {
112 var err error
113 g := GitRepo{path: path}
114 g.r, err = git.PlainOpen(path)
115 if err != nil {
116 return nil, fmt.Errorf("opening %s: %w", path, err)
117 }
118
119 if ref == "" {
120 head, err := g.r.Head()
121 if err != nil {
122 return nil, fmt.Errorf("getting head of %s: %w", path, err)
123 }
124 g.h = head.Hash()
125 } else {
126 hash, err := g.r.ResolveRevision(plumbing.Revision(ref))
127 if err != nil {
128 return nil, fmt.Errorf("resolving rev %s for %s: %w", ref, path, err)
129 }
130 g.h = *hash
131 }
132 return &g, nil
133}
134
135func PlainOpen(path string) (*GitRepo, error) {
136 var err error
137 g := GitRepo{path: path}
138 g.r, err = git.PlainOpen(path)
139 if err != nil {
140 return nil, fmt.Errorf("opening %s: %w", path, err)
141 }
142 return &g, nil
143}
144
145func (g *GitRepo) Commits() ([]*object.Commit, error) {
146 ci, err := g.r.Log(&git.LogOptions{From: g.h})
147 if err != nil {
148 return nil, fmt.Errorf("commits from ref: %w", err)
149 }
150
151 commits := []*object.Commit{}
152 ci.ForEach(func(c *object.Commit) error {
153 commits = append(commits, c)
154 return nil
155 })
156
157 return commits, nil
158}
159
160func (g *GitRepo) Commit(h plumbing.Hash) (*object.Commit, error) {
161 return g.r.CommitObject(h)
162}
163
164func (g *GitRepo) LastCommit() (*object.Commit, error) {
165 c, err := g.r.CommitObject(g.h)
166 if err != nil {
167 return nil, fmt.Errorf("last commit: %w", err)
168 }
169 return c, nil
170}
171
172func (g *GitRepo) FileContent(path string) (string, error) {
173 c, err := g.r.CommitObject(g.h)
174 if err != nil {
175 return "", fmt.Errorf("commit object: %w", err)
176 }
177
178 tree, err := c.Tree()
179 if err != nil {
180 return "", fmt.Errorf("file tree: %w", err)
181 }
182
183 file, err := tree.File(path)
184 if err != nil {
185 return "", err
186 }
187
188 isbin, _ := file.IsBinary()
189
190 if !isbin {
191 return file.Contents()
192 } else {
193 return "", ErrBinaryFile
194 }
195}
196
197func (g *GitRepo) BinContent(path string) ([]byte, error) {
198 c, err := g.r.CommitObject(g.h)
199 if err != nil {
200 return nil, fmt.Errorf("commit object: %w", err)
201 }
202
203 tree, err := c.Tree()
204 if err != nil {
205 return nil, fmt.Errorf("file tree: %w", err)
206 }
207
208 file, err := tree.File(path)
209 if err != nil {
210 return nil, err
211 }
212
213 isbin, _ := file.IsBinary()
214 if isbin {
215 reader, err := file.Reader()
216 if err != nil {
217 return nil, fmt.Errorf("opening file reader: %w", err)
218 }
219 defer reader.Close()
220
221 return io.ReadAll(reader)
222 }
223 return nil, ErrNotBinaryFile
224}
225
226func (g *GitRepo) Tags() ([]*TagReference, error) {
227 iter, err := g.r.Tags()
228 if err != nil {
229 return nil, fmt.Errorf("tag objects: %w", err)
230 }
231
232 tags := make([]*TagReference, 0)
233
234 if err := iter.ForEach(func(ref *plumbing.Reference) error {
235 obj, err := g.r.TagObject(ref.Hash())
236 switch err {
237 case nil:
238 tags = append(tags, &TagReference{
239 ref: ref,
240 tag: obj,
241 })
242 case plumbing.ErrObjectNotFound:
243 tags = append(tags, &TagReference{
244 ref: ref,
245 })
246 default:
247 return err
248 }
249 return nil
250 }); err != nil {
251 return nil, err
252 }
253
254 tagList := &TagList{r: g.r, refs: tags}
255 sort.Sort(tagList)
256 return tags, nil
257}
258
259func (g *GitRepo) Branches() ([]types.Branch, error) {
260 bi, err := g.r.Branches()
261 if err != nil {
262 return nil, fmt.Errorf("branchs: %w", err)
263 }
264
265 branches := []types.Branch{}
266
267 defaultBranch, err := g.FindMainBranch()
268 if err != nil {
269 return nil, fmt.Errorf("getting default branch", "error", err.Error())
270 }
271
272 _ = bi.ForEach(func(ref *plumbing.Reference) error {
273 b := types.Branch{}
274 b.Hash = ref.Hash().String()
275 b.Name = ref.Name().Short()
276
277 // resolve commit that this branch points to
278 commit, _ := g.Commit(ref.Hash())
279 if commit != nil {
280 b.Commit = commit
281 }
282
283 if defaultBranch != "" && defaultBranch == b.Name {
284 b.IsDefault = true
285 }
286
287 branches = append(branches, b)
288
289 return nil
290 })
291
292 return branches, nil
293}
294
295func (g *GitRepo) Branch(name string) (*plumbing.Reference, error) {
296 ref, err := g.r.Reference(plumbing.NewBranchReferenceName(name), false)
297 if err != nil {
298 return nil, fmt.Errorf("branch: %w", err)
299 }
300
301 if !ref.Name().IsBranch() {
302 return nil, fmt.Errorf("branch: %s is not a branch", ref.Name())
303 }
304
305 return ref, nil
306}
307
308func (g *GitRepo) SetDefaultBranch(branch string) error {
309 ref := plumbing.NewSymbolicReference(plumbing.HEAD, plumbing.NewBranchReferenceName(branch))
310 return g.r.Storer.SetReference(ref)
311}
312
313func (g *GitRepo) FindMainBranch() (string, error) {
314 ref, err := g.r.Head()
315 if err != nil {
316 return "", fmt.Errorf("unable to find main branch: %w", err)
317 }
318 if ref.Name().IsBranch() {
319 return strings.TrimPrefix(string(ref.Name()), "refs/heads/"), nil
320 }
321
322 return "", fmt.Errorf("unable to find main branch: %w", err)
323}
324
325// WriteTar writes itself from a tree into a binary tar file format.
326// prefix is root folder to be appended.
327func (g *GitRepo) WriteTar(w io.Writer, prefix string) error {
328 tw := tar.NewWriter(w)
329 defer tw.Close()
330
331 c, err := g.r.CommitObject(g.h)
332 if err != nil {
333 return fmt.Errorf("commit object: %w", err)
334 }
335
336 tree, err := c.Tree()
337 if err != nil {
338 return err
339 }
340
341 walker := object.NewTreeWalker(tree, true, nil)
342 defer walker.Close()
343
344 name, entry, err := walker.Next()
345 for ; err == nil; name, entry, err = walker.Next() {
346 info, err := newInfoWrapper(name, prefix, &entry, tree)
347 if err != nil {
348 return err
349 }
350
351 header, err := tar.FileInfoHeader(info, "")
352 if err != nil {
353 return err
354 }
355
356 err = tw.WriteHeader(header)
357 if err != nil {
358 return err
359 }
360
361 if !info.IsDir() {
362 file, err := tree.File(name)
363 if err != nil {
364 return err
365 }
366
367 reader, err := file.Blob.Reader()
368 if err != nil {
369 return err
370 }
371
372 _, err = io.Copy(tw, reader)
373 if err != nil {
374 reader.Close()
375 return err
376 }
377 reader.Close()
378 }
379 }
380
381 return nil
382}
383
384func (g *GitRepo) LastCommitForPath(path string) (*types.LastCommitInfo, error) {
385 cacheKey := fmt.Sprintf("%s:%s", g.h.String(), path)
386 cacheMu.RLock()
387 if commitInfo, found := commitCache.Get(cacheKey); found {
388 cacheMu.RUnlock()
389 return commitInfo.(*types.LastCommitInfo), nil
390 }
391 cacheMu.RUnlock()
392
393 cmd := exec.Command("git", "-C", g.path, "log", g.h.String(), "-1", "--format=%H %ct", "--", path)
394
395 var out bytes.Buffer
396 cmd.Stdout = &out
397 cmd.Stderr = &out
398
399 if err := cmd.Run(); err != nil {
400 return nil, fmt.Errorf("failed to get commit hash: %w", err)
401 }
402
403 output := strings.TrimSpace(out.String())
404 if output == "" {
405 return nil, fmt.Errorf("no commits found for path: %s", path)
406 }
407
408 parts := strings.SplitN(output, " ", 2)
409 if len(parts) < 2 {
410 return nil, fmt.Errorf("unexpected commit log format")
411 }
412
413 commitHash := parts[0]
414 commitTimeUnix, err := strconv.ParseInt(parts[1], 10, 64)
415 if err != nil {
416 return nil, fmt.Errorf("parsing commit time: %w", err)
417 }
418 commitTime := time.Unix(commitTimeUnix, 0)
419
420 hash := plumbing.NewHash(commitHash)
421
422 commitInfo := &types.LastCommitInfo{
423 Hash: hash,
424 Message: "",
425 When: commitTime,
426 }
427
428 cacheMu.Lock()
429 commitCache.Set(cacheKey, commitInfo, 1)
430 cacheMu.Unlock()
431
432 return commitInfo, nil
433}
434
435func newInfoWrapper(
436 name string,
437 prefix string,
438 entry *object.TreeEntry,
439 tree *object.Tree,
440) (*infoWrapper, error) {
441 var (
442 size int64
443 mode fs.FileMode
444 isDir bool
445 )
446
447 if entry.Mode.IsFile() {
448 file, err := tree.TreeEntryFile(entry)
449 if err != nil {
450 return nil, err
451 }
452 mode = fs.FileMode(file.Mode)
453
454 size, err = tree.Size(name)
455 if err != nil {
456 return nil, err
457 }
458 } else {
459 isDir = true
460 mode = fs.ModeDir | fs.ModePerm
461 }
462
463 fullname := path.Join(prefix, name)
464 return &infoWrapper{
465 name: fullname,
466 size: size,
467 mode: mode,
468 modTime: time.Unix(0, 0),
469 isDir: isDir,
470 }, nil
471}
472
473func (i *infoWrapper) Name() string {
474 return i.name
475}
476
477func (i *infoWrapper) Size() int64 {
478 return i.size
479}
480
481func (i *infoWrapper) Mode() fs.FileMode {
482 return i.mode
483}
484
485func (i *infoWrapper) ModTime() time.Time {
486 return i.modTime
487}
488
489func (i *infoWrapper) IsDir() bool {
490 return i.isDir
491}
492
493func (i *infoWrapper) Sys() any {
494 return nil
495}
496
497func (t *TagReference) Name() string {
498 return t.ref.Name().Short()
499}
500
501func (t *TagReference) Message() string {
502 if t.tag != nil {
503 return t.tag.Message
504 }
505 return ""
506}
507
508func (t *TagReference) TagObject() *object.Tag {
509 return t.tag
510}
511
512func (t *TagReference) Hash() plumbing.Hash {
513 return t.ref.Hash()
514}