git.go

  1// Package repository contains helper methods for working with the Git repo.
  2package repository
  3
  4import (
  5	"bytes"
  6	"fmt"
  7	"github.com/MichaelMure/git-bug/util"
  8	"io"
  9	"os"
 10	"os/exec"
 11	"strings"
 12)
 13
 14// GitRepo represents an instance of a (local) git repository.
 15type GitRepo struct {
 16	Path string
 17}
 18
 19// Run the given git command with the given I/O reader/writers, returning an error if it fails.
 20func (repo *GitRepo) runGitCommandWithIO(stdin io.Reader, stdout, stderr io.Writer, args ...string) error {
 21	//fmt.Println("Running git", strings.Join(args, " "))
 22
 23	cmd := exec.Command("git", args...)
 24	cmd.Dir = repo.Path
 25	cmd.Stdin = stdin
 26	cmd.Stdout = stdout
 27	cmd.Stderr = stderr
 28
 29	return cmd.Run()
 30}
 31
 32// Run the given git command and return its stdout, or an error if the command fails.
 33func (repo *GitRepo) runGitCommandRaw(stdin io.Reader, args ...string) (string, string, error) {
 34	var stdout bytes.Buffer
 35	var stderr bytes.Buffer
 36	err := repo.runGitCommandWithIO(stdin, &stdout, &stderr, args...)
 37	return strings.TrimSpace(stdout.String()), strings.TrimSpace(stderr.String()), err
 38}
 39
 40// Run the given git command and return its stdout, or an error if the command fails.
 41func (repo *GitRepo) runGitCommandWithStdin(stdin io.Reader, args ...string) (string, error) {
 42	stdout, stderr, err := repo.runGitCommandRaw(stdin, args...)
 43	if err != nil {
 44		if stderr == "" {
 45			stderr = "Error running git command: " + strings.Join(args, " ")
 46		}
 47		err = fmt.Errorf(stderr)
 48	}
 49	return stdout, err
 50}
 51
 52// Run the given git command and return its stdout, or an error if the command fails.
 53func (repo *GitRepo) runGitCommand(args ...string) (string, error) {
 54	return repo.runGitCommandWithStdin(nil, args...)
 55}
 56
 57// Run the given git command using the same stdin, stdout, and stderr as the review tool.
 58func (repo *GitRepo) runGitCommandInline(args ...string) error {
 59	return repo.runGitCommandWithIO(os.Stdin, os.Stdout, os.Stderr, args...)
 60}
 61
 62// NewGitRepo determines if the given working directory is inside of a git repository,
 63// and returns the corresponding GitRepo instance if it is.
 64func NewGitRepo(path string) (*GitRepo, error) {
 65	repo := &GitRepo{Path: path}
 66	_, err := repo.runGitCommand("rev-parse")
 67	if err == nil {
 68		return repo, nil
 69	}
 70	if _, ok := err.(*exec.ExitError); ok {
 71		return nil, err
 72	}
 73	return nil, err
 74}
 75
 76func InitGitRepo(path string) (*GitRepo, error) {
 77	repo := &GitRepo{Path: path}
 78	_, err := repo.runGitCommand("init", path)
 79	if err != nil {
 80		return nil, err
 81	}
 82	return repo, nil
 83}
 84
 85func InitBareGitRepo(path string) (*GitRepo, error) {
 86	repo := &GitRepo{Path: path}
 87	_, err := repo.runGitCommand("init", "--bare", path)
 88	if err != nil {
 89		return nil, err
 90	}
 91	return repo, nil
 92}
 93
 94// GetPath returns the path to the repo.
 95func (repo *GitRepo) GetPath() string {
 96	return repo.Path
 97}
 98
 99// GetUserName returns the name the the user has used to configure git
100func (repo *GitRepo) GetUserName() (string, error) {
101	return repo.runGitCommand("config", "user.name")
102}
103
104// GetUserEmail returns the email address that the user has used to configure git.
105func (repo *GitRepo) GetUserEmail() (string, error) {
106	return repo.runGitCommand("config", "user.email")
107}
108
109// GetCoreEditor returns the name of the editor that the user has used to configure git.
110func (repo *GitRepo) GetCoreEditor() (string, error) {
111	return repo.runGitCommand("var", "GIT_EDITOR")
112}
113
114// FetchRefs fetch git refs from a remote
115func (repo *GitRepo) FetchRefs(remote, refSpec string) error {
116	err := repo.runGitCommandInline("fetch", remote, refSpec)
117
118	if err != nil {
119		return fmt.Errorf("failed to fetch from the remote '%s': %v", remote, err)
120	}
121
122	return err
123}
124
125// PushRefs push git refs to a remote
126func (repo *GitRepo) PushRefs(remote string, refSpec string) error {
127	err := repo.runGitCommandInline("push", remote, refSpec)
128
129	if err != nil {
130		return fmt.Errorf("failed to push to the remote '%s': %v", remote, err)
131	}
132	return nil
133}
134
135// StoreData will store arbitrary data and return the corresponding hash
136func (repo *GitRepo) StoreData(data []byte) (util.Hash, error) {
137	var stdin = bytes.NewReader(data)
138
139	stdout, err := repo.runGitCommandWithStdin(stdin, "hash-object", "--stdin", "-w")
140
141	return util.Hash(stdout), err
142}
143
144// ReadData will attempt to read arbitrary data from the given hash
145func (repo *GitRepo) ReadData(hash util.Hash) ([]byte, error) {
146	var stdout bytes.Buffer
147	var stderr bytes.Buffer
148
149	err := repo.runGitCommandWithIO(nil, &stdout, &stderr, "cat-file", "-p", string(hash))
150
151	if err != nil {
152		return []byte{}, err
153	}
154
155	return stdout.Bytes(), nil
156}
157
158// StoreTree will store a mapping key-->Hash as a Git tree
159func (repo *GitRepo) StoreTree(entries []TreeEntry) (util.Hash, error) {
160	buffer := prepareTreeEntries(entries)
161
162	stdout, err := repo.runGitCommandWithStdin(&buffer, "mktree")
163
164	if err != nil {
165		return "", err
166	}
167
168	return util.Hash(stdout), nil
169}
170
171// StoreCommit will store a Git commit with the given Git tree
172func (repo *GitRepo) StoreCommit(treeHash util.Hash) (util.Hash, error) {
173	stdout, err := repo.runGitCommand("commit-tree", string(treeHash))
174
175	if err != nil {
176		return "", err
177	}
178
179	return util.Hash(stdout), nil
180}
181
182// StoreCommitWithParent will store a Git commit with the given Git tree
183func (repo *GitRepo) StoreCommitWithParent(treeHash util.Hash, parent util.Hash) (util.Hash, error) {
184	stdout, err := repo.runGitCommand("commit-tree", string(treeHash),
185		"-p", string(parent))
186
187	if err != nil {
188		return "", err
189	}
190
191	return util.Hash(stdout), nil
192}
193
194// UpdateRef will create or update a Git reference
195func (repo *GitRepo) UpdateRef(ref string, hash util.Hash) error {
196	_, err := repo.runGitCommand("update-ref", ref, string(hash))
197
198	return err
199}
200
201// ListRefs will return a list of Git ref matching the given refspec
202func (repo *GitRepo) ListRefs(refspec string) ([]string, error) {
203	stdout, err := repo.runGitCommand("for-each-ref", "--format=%(refname)", refspec)
204
205	if err != nil {
206		return nil, err
207	}
208
209	splitted := strings.Split(stdout, "\n")
210
211	if len(splitted) == 1 && splitted[0] == "" {
212		return []string{}, nil
213	}
214
215	return splitted, nil
216}
217
218// ListIds will return a list of Git ref matching the given refspec,
219// stripped to only the last part of the ref
220func (repo *GitRepo) ListIds(refspec string) ([]string, error) {
221	// the format option will strip the ref name to keep only the last part (ie, the bug id)
222	stdout, err := repo.runGitCommand("for-each-ref", "--format=%(refname:lstrip=-1)", refspec)
223
224	if err != nil {
225		return nil, err
226	}
227
228	splitted := strings.Split(stdout, "\n")
229
230	if len(splitted) == 1 && splitted[0] == "" {
231		return []string{}, nil
232	}
233
234	return splitted, nil
235}
236
237// RefExist will check if a reference exist in Git
238func (repo *GitRepo) RefExist(ref string) (bool, error) {
239	stdout, err := repo.runGitCommand("for-each-ref", ref)
240
241	if err != nil {
242		return false, err
243	}
244
245	return stdout != "", nil
246}
247
248// CopyRef will create a new reference with the same value as another one
249func (repo *GitRepo) CopyRef(source string, dest string) error {
250	_, err := repo.runGitCommand("update-ref", dest, source)
251
252	return err
253}
254
255// ListCommits will return the list of commit hashes of a ref, in chronological order
256func (repo *GitRepo) ListCommits(ref string) ([]util.Hash, error) {
257	stdout, err := repo.runGitCommand("rev-list", "--first-parent", "--reverse", ref)
258
259	if err != nil {
260		return nil, err
261	}
262
263	splitted := strings.Split(stdout, "\n")
264
265	casted := make([]util.Hash, len(splitted))
266	for i, line := range splitted {
267		casted[i] = util.Hash(line)
268	}
269
270	return casted, nil
271
272}
273
274// ListEntries will return the list of entries in a Git tree
275func (repo *GitRepo) ListEntries(hash util.Hash) ([]TreeEntry, error) {
276	stdout, err := repo.runGitCommand("ls-tree", string(hash))
277
278	if err != nil {
279		return nil, err
280	}
281
282	return readTreeEntries(stdout)
283}
284
285// FindCommonAncestor will return the last common ancestor of two chain of commit
286func (repo *GitRepo) FindCommonAncestor(hash1 util.Hash, hash2 util.Hash) (util.Hash, error) {
287	stdout, err := repo.runGitCommand("merge-base", string(hash1), string(hash2))
288
289	if err != nil {
290		return "", nil
291	}
292
293	return util.Hash(stdout), nil
294}
295
296// Return the git tree hash referenced in a commit
297func (repo *GitRepo) GetTreeHash(commit util.Hash) (util.Hash, error) {
298	stdout, err := repo.runGitCommand("rev-parse", string(commit)+"^{tree}")
299
300	if err != nil {
301		return "", nil
302	}
303
304	return util.Hash(stdout), nil
305}
306
307// Add a new remote to the repository
308func (repo *GitRepo) AddRemote(name string, url string) error {
309	_, err := repo.runGitCommand("remote", "add", name, url)
310
311	return err
312}