repo_cache_bug.go

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