repo_cache_bug.go

  1package cache
  2
  3import (
  4	"bytes"
  5	"encoding/gob"
  6	"errors"
  7	"fmt"
  8	"os"
  9	"path"
 10	"sort"
 11	"strings"
 12	"time"
 13
 14	"github.com/MichaelMure/git-bug/bug"
 15	"github.com/MichaelMure/git-bug/entity"
 16	"github.com/MichaelMure/git-bug/query"
 17	"github.com/MichaelMure/git-bug/repository"
 18	"github.com/blevesearch/bleve"
 19)
 20
 21const (
 22	bugCacheFile   = "bug-cache"
 23	searchCacheDir = "search-cache"
 24)
 25
 26var errBugNotInCache = errors.New("bug missing from cache")
 27
 28func bugCacheFilePath(repo repository.Repo) string {
 29	return path.Join(repo.GetPath(), "git-bug", bugCacheFile)
 30}
 31
 32func searchCacheDirPath(repo repository.Repo) string {
 33	return path.Join(repo.GetPath(), "git-bug", searchCacheDir)
 34}
 35
 36// bugUpdated is a callback to trigger when the excerpt of a bug changed,
 37// that is each time a bug is updated
 38func (c *RepoCache) bugUpdated(id entity.Id) error {
 39	c.muBug.Lock()
 40	b, ok := c.bugs[id]
 41	if !ok {
 42		c.muBug.Unlock()
 43
 44		// if the bug is not loaded at this point, it means it was loaded before
 45		// but got evicted. Which means we potentially have multiple copies in
 46		// memory and thus concurrent write.
 47		// Failing immediately here is the simple and safe solution to avoid
 48		// complicated data loss.
 49		return errBugNotInCache
 50	}
 51	c.loadedBugs.Get(id)
 52	c.bugExcerpts[id] = NewBugExcerpt(b.bug, b.Snapshot())
 53	c.muBug.Unlock()
 54
 55	if err := c.addBugToSearchIndex(b.Snapshot()); err != nil {
 56		return err
 57	}
 58
 59	// we only need to write the bug cache
 60	return c.writeBugCache()
 61}
 62
 63// load will try to read from the disk the bug cache file
 64func (c *RepoCache) loadBugCache() error {
 65	c.muBug.Lock()
 66	defer c.muBug.Unlock()
 67
 68	f, err := os.Open(bugCacheFilePath(c.repo))
 69	if err != nil {
 70		return err
 71	}
 72
 73	decoder := gob.NewDecoder(f)
 74
 75	aux := struct {
 76		Version  uint
 77		Excerpts map[entity.Id]*BugExcerpt
 78	}{}
 79
 80	err = decoder.Decode(&aux)
 81	if err != nil {
 82		return err
 83	}
 84
 85	if aux.Version != formatVersion {
 86		return fmt.Errorf("unknown cache format version %v", aux.Version)
 87	}
 88
 89	c.bugExcerpts = aux.Excerpts
 90
 91	blevePath := searchCacheDirPath(c.repo)
 92	searchCache, err := bleve.Open(blevePath)
 93	if err != nil {
 94		return fmt.Errorf("Unable to open search cache. Error: %v", err)
 95	}
 96	c.searchCache = searchCache
 97
 98	count, err := c.searchCache.DocCount()
 99	if err != nil {
100		return err
101	}
102	if count != uint64(len(c.bugExcerpts)) {
103		return fmt.Errorf("count mismatch between bleve and bug excerpts")
104	}
105
106	return nil
107}
108
109func (c *RepoCache) createBleveIndex() error {
110	blevePath := searchCacheDirPath(c.repo)
111
112	_ = os.RemoveAll(blevePath)
113
114	mapping := bleve.NewIndexMapping()
115	dir := searchCacheDirPath(c.repo)
116
117	bleveIndex, err := bleve.New(dir, mapping)
118	if err != nil {
119		return err
120	}
121
122	c.searchCache = bleveIndex
123
124	return nil
125}
126
127// write will serialize on disk the bug cache file
128func (c *RepoCache) writeBugCache() error {
129	c.muBug.RLock()
130	defer c.muBug.RUnlock()
131
132	var data bytes.Buffer
133
134	aux := struct {
135		Version  uint
136		Excerpts map[entity.Id]*BugExcerpt
137	}{
138		Version:  formatVersion,
139		Excerpts: c.bugExcerpts,
140	}
141
142	encoder := gob.NewEncoder(&data)
143
144	err := encoder.Encode(aux)
145	if err != nil {
146		return err
147	}
148
149	f, err := os.Create(bugCacheFilePath(c.repo))
150	if err != nil {
151		return err
152	}
153
154	_, err = f.Write(data.Bytes())
155	if err != nil {
156		return err
157	}
158
159	return f.Close()
160}
161
162// ResolveBugExcerpt retrieve a BugExcerpt matching the exact given id
163func (c *RepoCache) ResolveBugExcerpt(id entity.Id) (*BugExcerpt, error) {
164	c.muBug.RLock()
165	defer c.muBug.RUnlock()
166
167	excerpt, ok := c.bugExcerpts[id]
168	if !ok {
169		return nil, bug.ErrBugNotExist
170	}
171
172	return excerpt, nil
173}
174
175// ResolveBug retrieve a bug matching the exact given id
176func (c *RepoCache) ResolveBug(id entity.Id) (*BugCache, error) {
177	c.muBug.RLock()
178	cached, ok := c.bugs[id]
179	if ok {
180		c.loadedBugs.Get(id)
181		c.muBug.RUnlock()
182		return cached, nil
183	}
184	c.muBug.RUnlock()
185
186	b, err := bug.ReadLocalWithResolver(c.repo, newIdentityCacheResolver(c), id)
187	if err != nil {
188		return nil, err
189	}
190
191	cached = NewBugCache(c, b)
192
193	c.muBug.Lock()
194	c.bugs[id] = cached
195	c.loadedBugs.Add(id)
196	c.muBug.Unlock()
197
198	c.evictIfNeeded()
199
200	return cached, nil
201}
202
203// evictIfNeeded will evict a bug from the cache if needed
204// it also removes references of the bug from the bugs
205func (c *RepoCache) evictIfNeeded() {
206	c.muBug.Lock()
207	defer c.muBug.Unlock()
208	if c.loadedBugs.Len() <= c.maxLoadedBugs {
209		return
210	}
211
212	for _, id := range c.loadedBugs.GetOldestToNewest() {
213		b := c.bugs[id]
214		if b.NeedCommit() {
215			continue
216		}
217
218		b.mu.Lock()
219		c.loadedBugs.Remove(id)
220		delete(c.bugs, id)
221
222		if c.loadedBugs.Len() <= c.maxLoadedBugs {
223			return
224		}
225	}
226}
227
228// ResolveBugExcerptPrefix retrieve a BugExcerpt matching an id prefix. It fails if multiple
229// bugs match.
230func (c *RepoCache) ResolveBugExcerptPrefix(prefix string) (*BugExcerpt, error) {
231	return c.ResolveBugExcerptMatcher(func(excerpt *BugExcerpt) bool {
232		return excerpt.Id.HasPrefix(prefix)
233	})
234}
235
236// ResolveBugPrefix retrieve a bug matching an id prefix. It fails if multiple
237// bugs match.
238func (c *RepoCache) ResolveBugPrefix(prefix string) (*BugCache, error) {
239	return c.ResolveBugMatcher(func(excerpt *BugExcerpt) bool {
240		return excerpt.Id.HasPrefix(prefix)
241	})
242}
243
244// ResolveBugCreateMetadata retrieve a bug that has the exact given metadata on
245// its Create operation, that is, the first operation. It fails if multiple bugs
246// match.
247func (c *RepoCache) ResolveBugCreateMetadata(key string, value string) (*BugCache, error) {
248	return c.ResolveBugMatcher(func(excerpt *BugExcerpt) bool {
249		return excerpt.CreateMetadata[key] == value
250	})
251}
252
253func (c *RepoCache) ResolveBugExcerptMatcher(f func(*BugExcerpt) bool) (*BugExcerpt, error) {
254	id, err := c.resolveBugMatcher(f)
255	if err != nil {
256		return nil, err
257	}
258	return c.ResolveBugExcerpt(id)
259}
260
261func (c *RepoCache) ResolveBugMatcher(f func(*BugExcerpt) bool) (*BugCache, error) {
262	id, err := c.resolveBugMatcher(f)
263	if err != nil {
264		return nil, err
265	}
266	return c.ResolveBug(id)
267}
268
269func (c *RepoCache) resolveBugMatcher(f func(*BugExcerpt) bool) (entity.Id, error) {
270	c.muBug.RLock()
271	defer c.muBug.RUnlock()
272
273	// preallocate but empty
274	matching := make([]entity.Id, 0, 5)
275
276	for _, excerpt := range c.bugExcerpts {
277		if f(excerpt) {
278			matching = append(matching, excerpt.Id)
279		}
280	}
281
282	if len(matching) > 1 {
283		return entity.UnsetId, bug.NewErrMultipleMatchBug(matching)
284	}
285
286	if len(matching) == 0 {
287		return entity.UnsetId, bug.ErrBugNotExist
288	}
289
290	return matching[0], nil
291}
292
293// QueryBugs return the id of all Bug matching the given Query
294func (c *RepoCache) QueryBugs(q *query.Query) []entity.Id {
295	c.muBug.RLock()
296	defer c.muBug.RUnlock()
297
298	if q == nil {
299		return c.AllBugsIds()
300	}
301
302	matcher := compileMatcher(q.Filters)
303
304	var filtered []*BugExcerpt
305	var foundBySearch map[entity.Id]*BugExcerpt
306
307	if q.Search != nil {
308		foundBySearch = map[entity.Id]*BugExcerpt{}
309
310		terms := make([]string, len(q.Search))
311		copy(terms, q.Search)
312		for i, search := range q.Search {
313			if strings.Contains(search, " ") {
314				terms[i] = fmt.Sprintf("\"%s\"", search)
315			}
316		}
317
318		bleveQuery := bleve.NewQueryStringQuery(strings.Join(terms, " "))
319		bleveSearch := bleve.NewSearchRequest(bleveQuery)
320		searchResults, err := c.searchCache.Search(bleveSearch)
321		if err != nil {
322			panic("bleve search failed")
323		}
324
325		for _, hit := range searchResults.Hits {
326			foundBySearch[entity.Id(hit.ID)] = c.bugExcerpts[entity.Id(hit.ID)]
327		}
328	} else {
329		foundBySearch = c.bugExcerpts
330	}
331
332	for _, excerpt := range foundBySearch {
333		if matcher.Match(excerpt, c) {
334			filtered = append(filtered, excerpt)
335		}
336	}
337
338	var sorter sort.Interface
339
340	switch q.OrderBy {
341	case query.OrderById:
342		sorter = BugsById(filtered)
343	case query.OrderByCreation:
344		sorter = BugsByCreationTime(filtered)
345	case query.OrderByEdit:
346		sorter = BugsByEditTime(filtered)
347	default:
348		panic("missing sort type")
349	}
350
351	switch q.OrderDirection {
352	case query.OrderAscending:
353		// Nothing to do
354	case query.OrderDescending:
355		sorter = sort.Reverse(sorter)
356	default:
357		panic("missing sort direction")
358	}
359
360	sort.Sort(sorter)
361
362	result := make([]entity.Id, len(filtered))
363
364	for i, val := range filtered {
365		result[i] = val.Id
366	}
367
368	return result
369}
370
371// AllBugsIds return all known bug ids
372func (c *RepoCache) AllBugsIds() []entity.Id {
373	c.muBug.RLock()
374	defer c.muBug.RUnlock()
375
376	result := make([]entity.Id, len(c.bugExcerpts))
377
378	i := 0
379	for _, excerpt := range c.bugExcerpts {
380		result[i] = excerpt.Id
381		i++
382	}
383
384	return result
385}
386
387// ValidLabels list valid labels
388//
389// Note: in the future, a proper label policy could be implemented where valid
390// labels are defined in a configuration file. Until that, the default behavior
391// is to return the list of labels already used.
392func (c *RepoCache) ValidLabels() []bug.Label {
393	c.muBug.RLock()
394	defer c.muBug.RUnlock()
395
396	set := map[bug.Label]interface{}{}
397
398	for _, excerpt := range c.bugExcerpts {
399		for _, l := range excerpt.Labels {
400			set[l] = nil
401		}
402	}
403
404	result := make([]bug.Label, len(set))
405
406	i := 0
407	for l := range set {
408		result[i] = l
409		i++
410	}
411
412	// Sort
413	sort.Slice(result, func(i, j int) bool {
414		return string(result[i]) < string(result[j])
415	})
416
417	return result
418}
419
420// NewBug create a new bug
421// The new bug is written in the repository (commit)
422func (c *RepoCache) NewBug(title string, message string) (*BugCache, *bug.CreateOperation, error) {
423	return c.NewBugWithFiles(title, message, nil)
424}
425
426// NewBugWithFiles create a new bug with attached files for the message
427// The new bug is written in the repository (commit)
428func (c *RepoCache) NewBugWithFiles(title string, message string, files []repository.Hash) (*BugCache, *bug.CreateOperation, error) {
429	author, err := c.GetUserIdentity()
430	if err != nil {
431		return nil, nil, err
432	}
433
434	return c.NewBugRaw(author, time.Now().Unix(), title, message, files, nil)
435}
436
437// NewBugWithFilesMeta create a new bug with attached files for the message, as
438// well as metadata for the Create operation.
439// The new bug is written in the repository (commit)
440func (c *RepoCache) NewBugRaw(author *IdentityCache, unixTime int64, title string, message string, files []repository.Hash, metadata map[string]string) (*BugCache, *bug.CreateOperation, error) {
441	b, op, err := bug.CreateWithFiles(author.Identity, unixTime, title, message, files)
442	if err != nil {
443		return nil, nil, err
444	}
445
446	for key, value := range metadata {
447		op.SetMetadata(key, value)
448	}
449
450	err = b.Commit(c.repo)
451	if err != nil {
452		return nil, nil, err
453	}
454
455	c.muBug.Lock()
456	if _, has := c.bugs[b.Id()]; has {
457		c.muBug.Unlock()
458		return nil, nil, fmt.Errorf("bug %s already exist in the cache", b.Id())
459	}
460
461	cached := NewBugCache(c, b)
462	c.bugs[b.Id()] = cached
463	c.loadedBugs.Add(b.Id())
464	c.muBug.Unlock()
465
466	c.evictIfNeeded()
467
468	// force the write of the excerpt
469	err = c.bugUpdated(b.Id())
470	if err != nil {
471		return nil, nil, err
472	}
473
474	return cached, op, nil
475}
476
477// RemoveBug removes a bug from the cache and repo given a bug id prefix
478func (c *RepoCache) RemoveBug(prefix string) error {
479	c.muBug.RLock()
480
481	b, err := c.ResolveBugPrefix(prefix)
482	if err != nil {
483		c.muBug.RUnlock()
484		return err
485	}
486	c.muBug.RUnlock()
487
488	c.muBug.Lock()
489	err = bug.RemoveBug(c.repo, b.Id())
490
491	delete(c.bugs, b.Id())
492	delete(c.bugExcerpts, b.Id())
493	c.loadedBugs.Remove(b.Id())
494
495	c.muBug.Unlock()
496
497	return c.writeBugCache()
498}
499
500func (c *RepoCache) addBugToSearchIndex(snap *bug.Snapshot) error {
501	searchableBug := struct {
502		Text []string
503	}{}
504
505	for _, comment := range snap.Comments {
506		searchableBug.Text = append(searchableBug.Text, comment.Message)
507	}
508
509	searchableBug.Text = append(searchableBug.Text, snap.Title)
510
511	err := c.searchCache.Index(snap.Id().String(), searchableBug)
512	if err != nil {
513		return err
514	}
515
516	return nil
517}