fork of https://github.com/sourcegraph/zoekt
1// Copyright 2016 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15// Package gitindex provides functions for indexing Git repositories.
16package gitindex
17
18import (
19 "bytes"
20 "context"
21 "encoding/json"
22 "errors"
23 "fmt"
24 "io"
25 "log"
26 "math"
27 "net/url"
28 "os"
29 "path/filepath"
30 "sort"
31 "strconv"
32 "strings"
33 "time"
34
35 "github.com/sourcegraph/zoekt"
36 "github.com/sourcegraph/zoekt/build"
37 "github.com/sourcegraph/zoekt/ignore"
38
39 "github.com/go-git/go-git/v5/config"
40 "github.com/go-git/go-git/v5/plumbing"
41 "github.com/go-git/go-git/v5/plumbing/object"
42
43 git "github.com/go-git/go-git/v5"
44)
45
46// RepoModTime returns the time of last fetch of a git repository.
47func RepoModTime(dir string) (time.Time, error) {
48 var last time.Time
49 refDir := filepath.Join(dir, "refs")
50 if _, err := os.Lstat(refDir); err == nil {
51 if err := filepath.Walk(refDir,
52 func(_ string, fi os.FileInfo, _ error) error {
53 if !fi.IsDir() && last.Before(fi.ModTime()) {
54 last = fi.ModTime()
55 }
56 return nil
57 }); err != nil {
58 return last, err
59 }
60 }
61
62 // git gc compresses refs into the following file:
63 for _, fn := range []string{"info/refs", "packed-refs"} {
64 if fi, err := os.Lstat(filepath.Join(dir, fn)); err == nil && !fi.IsDir() && last.Before(fi.ModTime()) {
65 last = fi.ModTime()
66 }
67 }
68
69 return last, nil
70}
71
72// FindGitRepos finds directories holding git repositories below the
73// given directory. It will find both bare and the ".git" dirs in
74// non-bare repositories. It returns the full path including the dir
75// passed in.
76func FindGitRepos(dir string) ([]string, error) {
77 arg, err := filepath.Abs(dir)
78 if err != nil {
79 return nil, err
80 }
81 var dirs []string
82 if err := filepath.Walk(arg, func(name string, fi os.FileInfo, err error) error {
83 // Best-effort, ignore filepath.Walk failing
84 if err != nil {
85 return nil
86 }
87
88 if fi, err := os.Lstat(filepath.Join(name, ".git")); err == nil && fi.IsDir() {
89 dirs = append(dirs, filepath.Join(name, ".git"))
90 return filepath.SkipDir
91 }
92
93 if !strings.HasSuffix(name, ".git") || !fi.IsDir() {
94 return nil
95 }
96
97 fi, err = os.Lstat(filepath.Join(name, "objects"))
98 if err != nil || !fi.IsDir() {
99 return nil
100 }
101
102 dirs = append(dirs, name)
103 return filepath.SkipDir
104 }); err != nil {
105 return nil, err
106 }
107
108 return dirs, nil
109}
110
111// setTemplates fills in URL templates for known git hosting
112// sites.
113func setTemplates(repo *zoekt.Repository, u *url.URL, typ string) error {
114 repo.URL = u.String()
115 switch typ {
116 case "gitiles":
117 // eg. https://gerrit.googlesource.com/gitiles/+/master/tools/run_dev.sh#20
118 repo.CommitURLTemplate = u.String() + "/+/{{.Version}}"
119 repo.FileURLTemplate = u.String() + "/+/{{.Version}}/{{.Path}}"
120 repo.LineFragmentTemplate = "#{{.LineNumber}}"
121 case "github":
122 // eg. https://github.com/hanwen/go-fuse/blob/notify/genversion.sh#L10
123 repo.CommitURLTemplate = u.String() + "/commit/{{.Version}}"
124 repo.FileURLTemplate = u.String() + "/blob/{{.Version}}/{{.Path}}"
125 repo.LineFragmentTemplate = "#L{{.LineNumber}}"
126 case "cgit":
127 // http://git.savannah.gnu.org/cgit/lilypond.git/tree/elisp/lilypond-mode.el?h=dev/philh&id=b2ca0fefe3018477aaca23b6f672c7199ba5238e#n100
128 repo.CommitURLTemplate = u.String() + "/commit/?id={{.Version}}"
129 repo.FileURLTemplate = u.String() + "/tree/{{.Path}}/?id={{.Version}}"
130 repo.LineFragmentTemplate = "#n{{.LineNumber}}"
131 case "gitweb":
132 // https://gerrit.libreoffice.org/gitweb?p=online.git;a=blob;f=Makefile.am;h=cfcfd7c36fbae10e269653dc57a9b68c92d4c10b;hb=848145503bf7b98ce4a4aa0a858a0d71dd0dbb26#l10
133 repo.FileURLTemplate = u.String() + ";a=blob;f={{.Path}};hb={{.Version}}"
134 repo.CommitURLTemplate = u.String() + ";a=commit;h={{.Version}}"
135 repo.LineFragmentTemplate = "#l{{.LineNumber}}"
136 case "source.bazel.build":
137 // https://source.bazel.build/bazel/+/57bc201346e61c62a921c1cbf32ad24f185c10c9
138 // https://source.bazel.build/bazel/+/57bc201346e61c62a921c1cbf32ad24f185c10c9:tools/cpp/BUILD.empty;l=10
139 repo.CommitURLTemplate = u.String() + "/+/{{.Version}}"
140 repo.FileURLTemplate = u.String() + "/+/{{.Version}}:{{.Path}}"
141 repo.LineFragmentTemplate = ";l={{.LineNumber}}"
142 case "bitbucket-server":
143 // https://<bitbucketserver-host>/projects/<project>/repos/<repo>/commits/5be7ca73b898bf17a08e607918accfdeafe1e0bc
144 // https://<bitbucketserver-host>/projects/<project>/repos/<repo>/browse/<file>?at=5be7ca73b898bf17a08e607918accfdeafe1e0bc
145 repo.CommitURLTemplate = u.String() + "/commits/{{.Version}}"
146 repo.FileURLTemplate = u.String() + "/{{.Path}}?at={{.Version}}"
147 repo.LineFragmentTemplate = "#{{.LineNumber}}"
148 case "gitlab":
149 // https://gitlab.com/gitlab-org/omnibus-gitlab/-/commit/b152c864303dae0e55377a1e2c53c9592380ffed
150 // https://gitlab.com/gitlab-org/omnibus-gitlab/-/blob/aad04155b3f6fc50ede88aedaee7fc624d481149/files/gitlab-config-template/gitlab.rb.template
151 repo.CommitURLTemplate = u.String() + "/-/commit/{{.Version}}"
152 repo.FileURLTemplate = u.String() + "/-/blob/{{.Version}}/{{.Path}}"
153 repo.LineFragmentTemplate = "#L{{.LineNumber}}"
154 case "gitea":
155 repo.CommitURLTemplate = u.String() + "/commit/{{.Version}}"
156 // NOTE The `display=source` query parameter is required to disable file rendering.
157 // Since line numbers are disabled in rendered files, you wouldn't be able to jump to
158 // a line without `display=source`. This is supported since gitea 1.17.0.
159 // When /src/{{.Version}} is used it will redirect to /src/commit/{{.Version}},
160 // but the query parameters are obmitted.
161 repo.FileURLTemplate = u.String() + "/src/commit/{{.Version}}/{{.Path}}?display=source"
162 repo.LineFragmentTemplate = "#L{{.LineNumber}}"
163 default:
164 return fmt.Errorf("URL scheme type %q unknown", typ)
165 }
166 return nil
167}
168
169// getCommit returns a tree object for the given reference.
170func getCommit(repo *git.Repository, prefix, ref string) (*object.Commit, error) {
171 sha1, err := repo.ResolveRevision(plumbing.Revision(ref))
172 // ref might be a branch name (e.g. "master") add branch prefix and try again.
173 if err != nil {
174 sha1, err = repo.ResolveRevision(plumbing.Revision(filepath.Join(prefix, ref)))
175 }
176 if err != nil {
177 return nil, err
178 }
179
180 commitObj, err := repo.CommitObject(*sha1)
181 if err != nil {
182 return nil, err
183 }
184 return commitObj, nil
185}
186
187func configLookupRemoteURL(cfg *config.Config, key string) string {
188 rc := cfg.Remotes[key]
189 if rc == nil || len(rc.URLs) == 0 {
190 return ""
191 }
192 return rc.URLs[0]
193}
194
195func setTemplatesFromConfig(desc *zoekt.Repository, repoDir string) error {
196 repo, err := git.PlainOpen(repoDir)
197 if err != nil {
198 return err
199 }
200
201 cfg, err := repo.Config()
202 if err != nil {
203 return err
204 }
205
206 sec := cfg.Raw.Section("zoekt")
207
208 webURLStr := sec.Options.Get("web-url")
209 webURLType := sec.Options.Get("web-url-type")
210
211 if webURLType != "" && webURLStr != "" {
212 webURL, err := url.Parse(webURLStr)
213 if err != nil {
214 return err
215 }
216 if err := setTemplates(desc, webURL, webURLType); err != nil {
217 return err
218 }
219 } else if webURLStr != "" {
220 desc.URL = webURLStr
221 }
222
223 name := sec.Options.Get("name")
224 if name != "" {
225 desc.Name = name
226 } else {
227 remoteURL := configLookupRemoteURL(cfg, "origin")
228 if remoteURL == "" {
229 return nil
230 }
231 u, err := url.Parse(remoteURL)
232 if err != nil {
233 return err
234 }
235 if err := SetTemplatesFromOrigin(desc, u); err != nil {
236 return err
237 }
238 }
239
240 id, _ := strconv.ParseUint(sec.Options.Get("repoid"), 10, 32)
241 desc.ID = uint32(id)
242
243 if desc.RawConfig == nil {
244 desc.RawConfig = map[string]string{}
245 }
246 for _, o := range sec.Options {
247 desc.RawConfig[o.Key] = o.Value
248 }
249
250 // Ranking info.
251
252 // Github:
253 traction := 0
254 for _, s := range []string{"github-stars", "github-forks", "github-watchers", "github-subscribers"} {
255 f, err := strconv.Atoi(sec.Options.Get(s))
256 if err == nil {
257 traction += f
258 }
259 }
260
261 if strings.Contains(desc.Name, "googlesource.com/") && traction == 0 {
262 // Pretend everything on googlesource.com has 1000
263 // github stars.
264 traction = 1000
265 }
266
267 if traction > 0 {
268 l := math.Log(float64(traction))
269 desc.Rank = uint16((1.0 - 1.0/math.Pow(1+l, 0.6)) * 10000)
270 }
271
272 return nil
273}
274
275// SetTemplatesFromOrigin fills in templates based on the origin URL.
276func SetTemplatesFromOrigin(desc *zoekt.Repository, u *url.URL) error {
277 desc.Name = filepath.Join(u.Host, strings.TrimSuffix(u.Path, ".git"))
278
279 if strings.HasSuffix(u.Host, ".googlesource.com") {
280 return setTemplates(desc, u, "gitiles")
281 } else if u.Host == "github.com" {
282 u.Path = strings.TrimSuffix(u.Path, ".git")
283 return setTemplates(desc, u, "github")
284 } else {
285 return fmt.Errorf("unknown git hosting site %q", u)
286 }
287}
288
289// The Options structs controls details of the indexing process.
290type Options struct {
291 // The repository to be indexed.
292 RepoDir string
293
294 // If set, follow submodule links. This requires RepoCacheDir to be set.
295 Submodules bool
296
297 // If set, skip indexing if the existing index shard is newer
298 // than the refs in the repository.
299 Incremental bool
300
301 // Don't error out if some branch is missing
302 AllowMissingBranch bool
303
304 // Specifies the root of a Repository cache. Needed for submodule indexing.
305 RepoCacheDir string
306
307 // Indexing options.
308 BuildOptions build.Options
309
310 // Prefix of the branch to index, e.g. `remotes/origin`.
311 BranchPrefix string
312
313 // List of branch names to index, e.g. []string{"HEAD", "stable"}
314 Branches []string
315
316 // DeltaShardNumberFallbackThreshold defines an upper limit (inclusive) on the number of preexisting shards
317 // that can exist before attempting another delta build. If the number of preexisting shards exceeds this threshold,
318 // then a normal build will be performed instead.
319 //
320 // If DeltaShardNumberFallbackThreshold is 0, then this fallback behavior is disabled:
321 // a delta build will always be performed regardless of the number of preexisting shards.
322 DeltaShardNumberFallbackThreshold uint64
323}
324
325func expandBranches(repo *git.Repository, bs []string, prefix string) ([]string, error) {
326 var result []string
327 for _, b := range bs {
328 // Sourcegraph: We disable resolving refs. We want to return the exact ref
329 // requested so we can match it up.
330 if b == "HEAD" && false {
331 ref, err := repo.Head()
332 if err != nil {
333 return nil, err
334 }
335
336 result = append(result, strings.TrimPrefix(ref.Name().String(), prefix))
337 continue
338 }
339
340 if strings.Contains(b, "*") {
341 iter, err := repo.Branches()
342 if err != nil {
343 return nil, err
344 }
345
346 defer iter.Close()
347 for {
348 ref, err := iter.Next()
349 if err == io.EOF {
350 break
351 }
352 if err != nil {
353 return nil, err
354 }
355
356 name := ref.Name().Short()
357 if matched, err := filepath.Match(b, name); err != nil {
358 return nil, err
359 } else if !matched {
360 continue
361 }
362
363 result = append(result, strings.TrimPrefix(name, prefix))
364 }
365 continue
366 }
367
368 result = append(result, b)
369 }
370
371 return result, nil
372}
373
374// IndexGitRepo indexes the git repository as specified by the options.
375func IndexGitRepo(opts Options) error {
376 return indexGitRepo(opts, gitIndexConfig{})
377}
378
379// indexGitRepo indexes the git repository as specified by the options and the provided gitIndexConfig.
380func indexGitRepo(opts Options, config gitIndexConfig) error {
381 prepareDeltaBuild := prepareDeltaBuild
382 if config.prepareDeltaBuild != nil {
383 prepareDeltaBuild = config.prepareDeltaBuild
384 }
385
386 prepareNormalBuild := prepareNormalBuild
387 if config.prepareNormalBuild != nil {
388 prepareNormalBuild = config.prepareNormalBuild
389 }
390
391 // Set max thresholds, since we use them in this function.
392 opts.BuildOptions.SetDefaults()
393 if opts.RepoDir == "" {
394 return fmt.Errorf("gitindex: must set RepoDir")
395 }
396
397 opts.BuildOptions.RepositoryDescription.Source = opts.RepoDir
398 repo, err := git.PlainOpen(opts.RepoDir)
399 if err != nil {
400 return fmt.Errorf("git.PlainOpen: %w", err)
401 }
402
403 if err := setTemplatesFromConfig(&opts.BuildOptions.RepositoryDescription, opts.RepoDir); err != nil {
404 log.Printf("setTemplatesFromConfig(%s): %s", opts.RepoDir, err)
405 }
406
407 branches, err := expandBranches(repo, opts.Branches, opts.BranchPrefix)
408 if err != nil {
409 return fmt.Errorf("expandBranches: %w", err)
410 }
411 for _, b := range branches {
412 commit, err := getCommit(repo, opts.BranchPrefix, b)
413 if err != nil {
414 if opts.AllowMissingBranch && err.Error() == "reference not found" {
415 continue
416 }
417
418 return fmt.Errorf("getCommit: %w", err)
419 }
420
421 opts.BuildOptions.RepositoryDescription.Branches = append(opts.BuildOptions.RepositoryDescription.Branches, zoekt.RepositoryBranch{
422 Name: b,
423 Version: commit.Hash.String(),
424 })
425
426 if when := commit.Committer.When; when.After(opts.BuildOptions.RepositoryDescription.LatestCommitDate) {
427 opts.BuildOptions.RepositoryDescription.LatestCommitDate = when
428 }
429 }
430
431 if opts.Incremental && opts.BuildOptions.IncrementalSkipIndexing() {
432 return nil
433 }
434
435 // branch => (path, sha1) => repo.
436 var repos map[fileKey]BlobLocation
437
438 // fileKey => branches
439 var branchMap map[fileKey][]string
440
441 // Branch => Repo => SHA1
442 var branchVersions map[string]map[string]plumbing.Hash
443
444 // set of file paths that have been changed or deleted since
445 // the last indexed commit
446 //
447 // These only have an effect on delta builds
448 var changedOrRemovedFiles []string
449
450 if opts.BuildOptions.IsDelta {
451 repos, branchMap, branchVersions, changedOrRemovedFiles, err = prepareDeltaBuild(opts, repo)
452 if err != nil {
453 log.Printf("delta build: falling back to normal build since delta build failed, repository=%q, err=%s", opts.BuildOptions.RepositoryDescription.Name, err)
454 opts.BuildOptions.IsDelta = false
455 }
456 }
457
458 if !opts.BuildOptions.IsDelta {
459 repos, branchMap, branchVersions, err = prepareNormalBuild(opts, repo)
460 if err != nil {
461 return fmt.Errorf("preparing normal build: %w", err)
462 }
463 }
464
465 reposByPath := map[string]BlobLocation{}
466 for key, location := range repos {
467 reposByPath[key.SubRepoPath] = location
468 }
469
470 opts.BuildOptions.SubRepositories = map[string]*zoekt.Repository{}
471 for path, location := range reposByPath {
472 tpl := opts.BuildOptions.RepositoryDescription
473 if path != "" {
474 tpl = zoekt.Repository{URL: location.URL.String()}
475 if err := SetTemplatesFromOrigin(&tpl, location.URL); err != nil {
476 log.Printf("setTemplatesFromOrigin(%s, %s): %s", path, location.URL, err)
477 }
478 }
479 opts.BuildOptions.SubRepositories[path] = &tpl
480 }
481
482 for _, br := range opts.BuildOptions.RepositoryDescription.Branches {
483 for path, repo := range opts.BuildOptions.SubRepositories {
484 id := branchVersions[br.Name][path]
485 repo.Branches = append(repo.Branches, zoekt.RepositoryBranch{
486 Name: br.Name,
487 Version: id.String(),
488 })
489 }
490 }
491
492 builder, err := build.NewBuilder(opts.BuildOptions)
493 if err != nil {
494 return fmt.Errorf("build.NewBuilder: %w", err)
495 }
496
497 var ranks repoPathRanks
498 var meanRank float64
499 if opts.BuildOptions.DocumentRanksPath != "" {
500 data, err := os.ReadFile(opts.BuildOptions.DocumentRanksPath)
501 if err != nil {
502 return err
503 }
504
505 err = json.Unmarshal(data, &ranks)
506 if err != nil {
507 return err
508 }
509
510 // Compute the mean rank for this repository. Note: we overwrite the rank
511 // mean that's stored in the document ranks file, since that currently
512 // represents a global mean rank across repos, which is not what we want.
513 numRanks := len(ranks.Paths)
514 if numRanks > 0 {
515 for _, rank := range ranks.Paths {
516 meanRank += rank
517 }
518 ranks.MeanRank = meanRank / float64(numRanks)
519 }
520 }
521
522 // we don't need to check error, since we either already have an error, or
523 // we returning the first call to builder.Finish.
524 defer builder.Finish() // nolint:errcheck
525
526 for _, f := range changedOrRemovedFiles {
527 builder.MarkFileAsChangedOrRemoved(f)
528 }
529
530 var names []string
531 fileKeys := map[string][]fileKey{}
532 for key := range repos {
533 n := key.FullPath()
534 fileKeys[n] = append(fileKeys[n], key)
535 names = append(names, n)
536 }
537
538 sort.Strings(names)
539 names = uniq(names)
540
541 for _, name := range names {
542 keys := fileKeys[name]
543
544 for _, key := range keys {
545 brs := branchMap[key]
546 blob, err := repos[key].Repo.BlobObject(key.ID)
547 if err != nil {
548 return err
549 }
550
551 keyFullPath := key.FullPath()
552
553 if blob.Size > int64(opts.BuildOptions.SizeMax) && !opts.BuildOptions.IgnoreSizeMax(keyFullPath) {
554 if err := builder.Add(zoekt.Document{
555 SkipReason: fmt.Sprintf("file size %d exceeds maximum size %d", blob.Size, opts.BuildOptions.SizeMax),
556 Name: keyFullPath,
557 Branches: brs,
558 SubRepositoryPath: key.SubRepoPath,
559 }); err != nil {
560 return err
561 }
562 continue
563 }
564
565 contents, err := blobContents(blob)
566 if err != nil {
567 return err
568 }
569
570 var pathRanks []float64
571 if len(ranks.Paths) > 0 {
572 // If the repository has ranking data, then store the file's rank.
573 pathRank := ranks.rank(keyFullPath)
574 pathRanks = []float64{pathRank}
575 }
576
577 if err := builder.Add(zoekt.Document{
578 SubRepositoryPath: key.SubRepoPath,
579 Name: keyFullPath,
580 Content: contents,
581 Branches: brs,
582 Ranks: pathRanks,
583 }); err != nil {
584 return fmt.Errorf("error adding document with name %s: %w", keyFullPath, err)
585 }
586 }
587 }
588
589 return builder.Finish()
590}
591
592type repoPathRanks struct {
593 MeanRank float64 `json:"mean_reference_count"`
594 Paths map[string]float64 `json:"paths"`
595}
596
597// rank returns the rank for a given path. It uses these rules:
598// - If we have a concrete rank for this file, always use it
599// - If there's no rank, and it's a low priority file like a test, then use rank 0
600// - Otherwise use the mean rank of this repository, to avoid giving it a big disadvantage
601func (r repoPathRanks) rank(path string) float64 {
602 if rank, ok := r.Paths[path]; ok {
603 return rank
604 } else if build.IsLowPriority(path) {
605 return 0.0
606 } else {
607 return r.MeanRank
608 }
609}
610
611func newIgnoreMatcher(tree *object.Tree) (*ignore.Matcher, error) {
612 ignoreFile, err := tree.File(ignore.IgnoreFile)
613 if err == object.ErrFileNotFound {
614 return &ignore.Matcher{}, nil
615 }
616 if err != nil {
617 return nil, err
618 }
619 content, err := ignoreFile.Contents()
620 if err != nil {
621 return nil, err
622 }
623 return ignore.ParseIgnoreFile(strings.NewReader(content))
624}
625
626// prepareDeltaBuildFunc is a function that calculates the necessary metadata for preparing
627// a build.Builder instance for generating a delta build.
628type prepareDeltaBuildFunc func(options Options, repository *git.Repository) (repos map[fileKey]BlobLocation, branchMap map[fileKey][]string, branchVersions map[string]map[string]plumbing.Hash, changedOrDeletedPaths []string, err error)
629
630// prepareNormalBuildFunc is a function that calculates the necessary metadata for preparing
631// a build.Builder instance for generating a normal build.
632type prepareNormalBuildFunc func(options Options, repository *git.Repository) (repos map[fileKey]BlobLocation, branchMap map[fileKey][]string, branchVersions map[string]map[string]plumbing.Hash, err error)
633
634type gitIndexConfig struct {
635 // prepareDeltaBuild, if not nil, is the function that is used to calculate the metadata that will be used to
636 // prepare the build.Builder instance for generating a delta build.
637 //
638 // If prepareDeltaBuild is nil, gitindex.prepareDeltaBuild will be used instead.
639 prepareDeltaBuild prepareDeltaBuildFunc
640
641 // prepareNormalBuild, if not nil, is the function that is used to calculate the metadata that will be used to
642 // prepare the build.Builder instance for generating a normal build.
643 //
644 // If prepareNormalBuild is nil, gitindex.prepareNormalBuild will be used instead.
645 prepareNormalBuild prepareNormalBuildFunc
646}
647
648func prepareDeltaBuild(options Options, repository *git.Repository) (repos map[fileKey]BlobLocation, branchMap map[fileKey][]string, branchVersions map[string]map[string]plumbing.Hash, changedOrDeletedPaths []string, err error) {
649 if options.Submodules {
650 return nil, nil, nil, nil, fmt.Errorf("delta builds currently don't support submodule indexing")
651 }
652
653 // discover what commits we indexed during our last build
654 existingRepository, ok, err := options.BuildOptions.FindRepositoryMetadata()
655 if err != nil {
656 return nil, nil, nil, nil, fmt.Errorf("failed to get repository metadata: %w", err)
657 }
658
659 if !ok {
660 return nil, nil, nil, nil, fmt.Errorf("no existing shards found for repository")
661 }
662
663 if options.DeltaShardNumberFallbackThreshold > 0 {
664 // HACK: For our interim compaction strategy, we force a full normal index once
665 // the number of shards on disk for this repository exceeds the provided threshold.
666 //
667 // This strategy obviously isn't optimal (as an example: we currently can't differentiate
668 // between "normal" and "delta" shards, so repositories like the gigarepo that generate a large number of shards per
669 // build would be disproportionately affected by this), but it'll allow us to continue experimenting on real workloads
670 // while we create a better compaction strategy).
671
672 oldShards := options.BuildOptions.FindAllShards()
673 if uint64(len(oldShards)) > options.DeltaShardNumberFallbackThreshold {
674 return nil, nil, nil, nil, fmt.Errorf("number of existing shards (%d) > requested shard threshold (%d)", len(oldShards), options.DeltaShardNumberFallbackThreshold)
675 }
676 }
677
678 // Check to see if the set of branch names is consistent with what we last indexed.
679 // If it isn't consistent, that we can't proceed with a delta build (and the caller should fall back to a
680 // normal one).
681
682 if !build.BranchNamesEqual(existingRepository.Branches, options.BuildOptions.RepositoryDescription.Branches) {
683 var existingBranchNames []string
684 for _, b := range existingRepository.Branches {
685 existingBranchNames = append(existingBranchNames, b.Name)
686 }
687
688 var optionsBranchNames []string
689 for _, b := range options.BuildOptions.RepositoryDescription.Branches {
690 optionsBranchNames = append(optionsBranchNames, b.Name)
691 }
692
693 existingBranchList := strings.Join(existingBranchNames, ", ")
694 optionsBranchList := strings.Join(optionsBranchNames, ", ")
695
696 return nil, nil, nil, nil, fmt.Errorf("requested branch set in build options (%q) != branch set found on disk (%q) - branch set must be the same for delta shards", optionsBranchList, existingBranchList)
697 }
698
699 // Check if the build options hash does not match the repository metadata's hash
700 // If it does not match then one or more index options has changed and will require a normal build instead of a delta build
701 if options.BuildOptions.GetHash() != existingRepository.IndexOptions {
702 return nil, nil, nil, nil, fmt.Errorf("one or more index options previously stored for repository %s (ID: %d) does not match the index options for this requested build; These index option updates are incompatible with delta build. new index options: %+v", existingRepository.Name, existingRepository.ID, options.BuildOptions.HashOptions())
703 }
704
705 // branch => (path, sha1) => repo.
706 repos = map[fileKey]BlobLocation{}
707
708 // fileKey => branches
709 branchMap = map[fileKey][]string{}
710
711 // branch name -> git worktree at most current commit
712 branchToCurrentTree := make(map[string]*object.Tree, len(options.Branches))
713
714 for _, b := range options.Branches {
715 commit, err := getCommit(repository, options.BranchPrefix, b)
716 if err != nil {
717 return nil, nil, nil, nil, fmt.Errorf("getting last current commit for branch %q: %w", b, err)
718 }
719
720 tree, err := commit.Tree()
721 if err != nil {
722 return nil, nil, nil, nil, fmt.Errorf("getting current git tree for branch %q: %w", b, err)
723 }
724
725 branchToCurrentTree[b] = tree
726 }
727
728 rawURL := options.BuildOptions.RepositoryDescription.URL
729 u, err := url.Parse(rawURL)
730 if err != nil {
731 return nil, nil, nil, nil, fmt.Errorf("parsing repository URL %q: %w", rawURL, err)
732 }
733
734 // TODO: Support repository submodules for delta builds
735 // For this prototype, we are ignoring repository submodules, which means that we can use the same
736 // blob location for all files
737 hackSharedBlobLocation := BlobLocation{
738 Repo: repository,
739 URL: u,
740 }
741
742 // loop over all branches, calculate the diff between our
743 // last indexed commit and the current commit, and add files mentioned in the diff
744 for _, branch := range existingRepository.Branches {
745 lastIndexedCommit, err := getCommit(repository, "", branch.Version)
746 if err != nil {
747 return nil, nil, nil, nil, fmt.Errorf("getting last indexed commit for branch %q: %w", branch.Name, err)
748 }
749
750 lastIndexedTree, err := lastIndexedCommit.Tree()
751 if err != nil {
752 return nil, nil, nil, nil, fmt.Errorf("getting lasted indexed git tree for branch %q: %w", branch.Name, err)
753 }
754
755 changes, err := object.DiffTreeWithOptions(context.Background(), lastIndexedTree, branchToCurrentTree[branch.Name], &object.DiffTreeOptions{DetectRenames: false})
756 if err != nil {
757 return nil, nil, nil, nil, fmt.Errorf("generating changeset for branch %q: %w", branch.Name, err)
758 }
759
760 for i, c := range changes {
761 oldFile, newFile, err := c.Files()
762 if err != nil {
763 return nil, nil, nil, nil, fmt.Errorf("change #%d: getting files before and after change: %w", i, err)
764 }
765
766 if newFile != nil {
767 // note: newFile.Name could be a path that isn't relative to the repository root - using the
768 // change's Name field is the only way that @ggilmore saw to get the full path relative to the root
769 newFileRelativeRootPath := c.To.Name
770
771 // TODO@ggilmore: HACK - remove once ignore files are supported in delta builds
772 if newFileRelativeRootPath == ignore.IgnoreFile {
773 return nil, nil, nil, nil, fmt.Errorf("%q file is not yet supported in delta builds", ignore.IgnoreFile)
774 }
775
776 // either file is added or renamed, so we need to add the new version to the build
777 file := fileKey{Path: newFileRelativeRootPath, ID: newFile.Hash}
778 repos[file] = hackSharedBlobLocation
779 branchMap[file] = append(branchMap[file], branch.Name)
780 }
781
782 if oldFile == nil {
783 // file added - nothing more to do
784 continue
785 }
786
787 // Note: oldFile.Name could be a path that isn't relative to the repository root - using the
788 // change's "Name" field is the only way that ggilmore saw to get the full path relative to the root
789 oldFileRelativeRootPath := c.From.Name
790
791 if oldFileRelativeRootPath == ignore.IgnoreFile {
792 return nil, nil, nil, nil, fmt.Errorf("%q file is not yet supported in delta builds", ignore.IgnoreFile)
793 }
794
795 // The file is either modified or deleted. So, we need to add ALL versions
796 // of the old file (across all branches) to the build.
797 for b, currentTree := range branchToCurrentTree {
798 f, err := currentTree.File(oldFileRelativeRootPath)
799 if err != nil {
800 // the file doesn't exist in this branch
801 if errors.Is(err, object.ErrFileNotFound) {
802 continue
803 }
804
805 return nil, nil, nil, nil, fmt.Errorf("getting hash for file %q in branch %q: %w", oldFile.Name, b, err)
806 }
807
808 file := fileKey{Path: oldFileRelativeRootPath, ID: f.ID()}
809 repos[file] = hackSharedBlobLocation
810 branchMap[file] = append(branchMap[file], b)
811 }
812
813 changedOrDeletedPaths = append(changedOrDeletedPaths, oldFileRelativeRootPath)
814 }
815 }
816
817 // we need to de-duplicate the branch map before returning it - it's possible for the same
818 // branch to have been added multiple times if a file has been modified across multiple commits
819
820 for file, branches := range branchMap {
821 sort.Strings(branches)
822 branchMap[file] = uniq(branches)
823 }
824
825 // we also need to de-duplicate the list of changed or deleted file paths, it's also possible to have duplicates
826 // for the same reasoning as above
827
828 sort.Strings(changedOrDeletedPaths)
829 changedOrDeletedPaths = uniq(changedOrDeletedPaths)
830
831 return repos, branchMap, nil, changedOrDeletedPaths, nil
832}
833
834func prepareNormalBuild(options Options, repository *git.Repository) (repos map[fileKey]BlobLocation, branchMap map[fileKey][]string, branchVersions map[string]map[string]plumbing.Hash, err error) {
835 var repoCache *RepoCache
836 if options.Submodules {
837 repoCache = NewRepoCache(options.RepoCacheDir)
838 }
839
840 // branch => (path, sha1) => repo.
841 repos = map[fileKey]BlobLocation{}
842
843 // fileKey => branches
844 branchMap = map[fileKey][]string{}
845
846 // Branch => Repo => SHA1
847 branchVersions = map[string]map[string]plumbing.Hash{}
848
849 branches, err := expandBranches(repository, options.Branches, options.BranchPrefix)
850 if err != nil {
851 return nil, nil, nil, fmt.Errorf("expandBranches: %w", err)
852 }
853
854 for _, b := range branches {
855 commit, err := getCommit(repository, options.BranchPrefix, b)
856 if err != nil {
857 if options.AllowMissingBranch && err.Error() == "reference not found" {
858 continue
859 }
860
861 return nil, nil, nil, fmt.Errorf("getCommit: %w", err)
862 }
863
864 tree, err := commit.Tree()
865 if err != nil {
866 return nil, nil, nil, fmt.Errorf("commit.Tree: %w", err)
867 }
868
869 ig, err := newIgnoreMatcher(tree)
870 if err != nil {
871 return nil, nil, nil, fmt.Errorf("newIgnoreMatcher: %w", err)
872 }
873
874 files, subVersions, err := TreeToFiles(repository, tree, options.BuildOptions.RepositoryDescription.URL, repoCache)
875 if err != nil {
876 return nil, nil, nil, fmt.Errorf("TreeToFiles: %w", err)
877 }
878 for k, v := range files {
879 if ig.Match(k.Path) {
880 continue
881 }
882 repos[k] = v
883 branchMap[k] = append(branchMap[k], b)
884 }
885
886 branchVersions[b] = subVersions
887 }
888
889 return repos, branchMap, branchVersions, nil
890}
891
892func blobContents(blob *object.Blob) ([]byte, error) {
893 r, err := blob.Reader()
894 if err != nil {
895 return nil, err
896 }
897 defer r.Close()
898
899 var buf bytes.Buffer
900 buf.Grow(int(blob.Size))
901 _, err = buf.ReadFrom(r)
902 if err != nil {
903 return nil, err
904 }
905 return buf.Bytes(), nil
906}
907
908func uniq(ss []string) []string {
909 result := ss[:0]
910 var last string
911 for i, s := range ss {
912 if i == 0 || s != last {
913 result = append(result, s)
914 }
915 last = s
916 }
917 return result
918}