repo_cache.go

  1package cache
  2
  3import (
  4	"bytes"
  5	"encoding/gob"
  6	"fmt"
  7	"io"
  8	"os"
  9	"path"
 10	"strings"
 11
 12	"github.com/MichaelMure/git-bug/bug"
 13	"github.com/MichaelMure/git-bug/bug/operations"
 14	"github.com/MichaelMure/git-bug/repository"
 15	"github.com/MichaelMure/git-bug/util"
 16)
 17
 18type RepoCache struct {
 19	repo     repository.Repo
 20	excerpts map[string]BugExcerpt
 21	bugs     map[string]*BugCache
 22}
 23
 24func NewRepoCache(r repository.Repo) (*RepoCache, error) {
 25	c := &RepoCache{
 26		repo: r,
 27		bugs: make(map[string]*BugCache),
 28	}
 29
 30	err := c.loadExcerpts()
 31
 32	if err == nil {
 33		return c, nil
 34	}
 35
 36	c.buildAllExcerpt()
 37
 38	return c, c.writeExcerpts()
 39}
 40
 41func (c *RepoCache) Repository() repository.Repo {
 42	return c.repo
 43}
 44
 45// bugUpdated is a callback to trigger when the excerpt of a bug changed,
 46// that is each time a bug is updated
 47func (c *RepoCache) bugUpdated(id string) error {
 48	b, ok := c.bugs[id]
 49	if !ok {
 50		panic("missing bug in the cache")
 51	}
 52
 53	c.excerpts[id] = NewBugExcerpt(b.bug, b.Snapshot())
 54
 55	return c.writeExcerpts()
 56}
 57
 58// loadExcerpts will try to read from the disk the bug excerpt file
 59func (c *RepoCache) loadExcerpts() error {
 60	excerptsPath := repoExcerptsFilePath(c.repo)
 61
 62	f, err := os.Open(excerptsPath)
 63	if err != nil {
 64		return err
 65	}
 66
 67	decoder := gob.NewDecoder(f)
 68
 69	var excerpts map[string]BugExcerpt
 70
 71	err = decoder.Decode(&excerpts)
 72	if err != nil {
 73		return err
 74	}
 75
 76	c.excerpts = excerpts
 77	return nil
 78}
 79
 80// writeExcerpts will serialize on disk the BugExcerpt array
 81func (c *RepoCache) writeExcerpts() error {
 82	var data bytes.Buffer
 83
 84	encoder := gob.NewEncoder(&data)
 85
 86	err := encoder.Encode(c.excerpts)
 87	if err != nil {
 88		return err
 89	}
 90
 91	excerptsPath := repoExcerptsFilePath(c.repo)
 92
 93	f, err := os.Create(excerptsPath)
 94	if err != nil {
 95		return err
 96	}
 97
 98	_, err = f.Write(data.Bytes())
 99	if err != nil {
100		return err
101	}
102
103	return f.Close()
104}
105
106func repoExcerptsFilePath(repo repository.Repo) string {
107	return path.Join(repo.GetPath(), ".git", "git-bug", excerptsFile)
108}
109
110func (c *RepoCache) buildAllExcerpt() {
111	c.excerpts = make(map[string]BugExcerpt)
112
113	allBugs := bug.ReadAllLocalBugs(c.repo)
114
115	for b := range allBugs {
116		snap := b.Bug.Compile()
117		c.excerpts[b.Bug.Id()] = NewBugExcerpt(b.Bug, &snap)
118	}
119}
120
121func (c *RepoCache) ResolveBug(id string) (*BugCache, error) {
122	cached, ok := c.bugs[id]
123	if ok {
124		return cached, nil
125	}
126
127	b, err := bug.ReadLocalBug(c.repo, id)
128	if err != nil {
129		return nil, err
130	}
131
132	cached = NewBugCache(c, b)
133	c.bugs[id] = cached
134
135	return cached, nil
136}
137
138func (c *RepoCache) ResolveBugPrefix(prefix string) (*BugCache, error) {
139	// preallocate but empty
140	matching := make([]string, 0, 5)
141
142	for id := range c.bugs {
143		if strings.HasPrefix(id, prefix) {
144			matching = append(matching, id)
145		}
146	}
147
148	// TODO: should check matching bug in the repo as well
149
150	if len(matching) > 1 {
151		return nil, fmt.Errorf("Multiple matching bug found:\n%s", strings.Join(matching, "\n"))
152	}
153
154	if len(matching) == 1 {
155		b := c.bugs[matching[0]]
156		return b, nil
157	}
158
159	b, err := bug.FindLocalBug(c.repo, prefix)
160
161	if err != nil {
162		return nil, err
163	}
164
165	cached := NewBugCache(c, b)
166	c.bugs[b.Id()] = cached
167
168	return cached, nil
169}
170
171func (c *RepoCache) AllBugIds() ([]string, error) {
172	return bug.ListLocalIds(c.repo)
173}
174
175func (c *RepoCache) ClearAllBugs() {
176	c.bugs = make(map[string]*BugCache)
177}
178
179func (c *RepoCache) NewBug(title string, message string) (*BugCache, error) {
180	return c.NewBugWithFiles(title, message, nil)
181}
182
183func (c *RepoCache) NewBugWithFiles(title string, message string, files []util.Hash) (*BugCache, error) {
184	author, err := bug.GetUser(c.repo)
185	if err != nil {
186		return nil, err
187	}
188
189	b, err := operations.CreateWithFiles(author, title, message, files)
190	if err != nil {
191		return nil, err
192	}
193
194	err = b.Commit(c.repo)
195	if err != nil {
196		return nil, err
197	}
198
199	cached := NewBugCache(c, b)
200	c.bugs[b.Id()] = cached
201
202	return cached, nil
203}
204
205func (c *RepoCache) Fetch(remote string) (string, error) {
206	return bug.Fetch(c.repo, remote)
207}
208
209func (c *RepoCache) MergeAll(remote string) <-chan bug.MergeResult {
210	return bug.MergeAll(c.repo, remote)
211}
212
213func (c *RepoCache) Pull(remote string, out io.Writer) error {
214	return bug.Pull(c.repo, out, remote)
215}
216
217func (c *RepoCache) Push(remote string) (string, error) {
218	return bug.Push(c.repo, remote)
219}