repo_cache_bug.go

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