aboutsummaryrefslogtreecommitdiffstats
path: root/repository/git.go
blob: 8c20d0b8a30956410114fffc8b0ab6c12231109e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
// Package repository contains helper methods for working with the Git repo.
package repository

import (
	"bytes"
	"crypto/sha1"
	"fmt"
	"github.com/MichaelMure/git-bug/util"
	"io"
	"os/exec"
	"strings"
)

// This is used to have a different staging area than the regular git index
// when creating data in git
const gitEnvConfig = "GIT_INDEX_FILE=BUG_STAGING_INDEX"

// GitRepo represents an instance of a (local) git repository.
type GitRepo struct {
	Path string
}

// Run the given git command with the given I/O reader/writers, returning an error if it fails.
func (repo *GitRepo) runGitCommandWithIO(stdin io.Reader, stdout, stderr io.Writer, args ...string) error {
	cmd := exec.Command("git", args...)
	cmd.Dir = repo.Path
	cmd.Stdin = stdin
	cmd.Stdout = stdout
	cmd.Stderr = stderr

	//cmd.Env = append(cmd.Env, gitEnvConfig)

	return cmd.Run()
}

// Run the given git command and return its stdout, or an error if the command fails.
func (repo *GitRepo) runGitCommandRaw(stdin io.Reader, args ...string) (string, string, error) {
	var stdout bytes.Buffer
	var stderr bytes.Buffer
	err := repo.runGitCommandWithIO(stdin, &stdout, &stderr, args...)
	return strings.TrimSpace(stdout.String()), strings.TrimSpace(stderr.String()), err
}

// Run the given git command and return its stdout, or an error if the command fails.
func (repo *GitRepo) runGitCommandWithStdin(stdin io.Reader, args ...string) (string, error) {
	stdout, stderr, err := repo.runGitCommandRaw(stdin, args...)
	if err != nil {
		if stderr == "" {
			stderr = "Error running git command: " + strings.Join(args, " ")
		}
		err = fmt.Errorf(stderr)
	}
	return stdout, err
}

// Run the given git command and return its stdout, or an error if the command fails.
func (repo *GitRepo) runGitCommand(args ...string) (string, error) {
	return repo.runGitCommandWithStdin(nil, args...)
}

// NewGitRepo determines if the given working directory is inside of a git repository,
// and returns the corresponding GitRepo instance if it is.
func NewGitRepo(path string) (*GitRepo, error) {
	repo := &GitRepo{Path: path}
	_, err := repo.runGitCommand("rev-parse")
	if err == nil {
		return repo, nil
	}
	if _, ok := err.(*exec.ExitError); ok {
		return nil, err
	}
	return nil, err
}

// GetPath returns the path to the repo.
func (repo *GitRepo) GetPath() string {
	return repo.Path
}

// GetRepoStateHash returns a hash which embodies the entire current state of a repository.
func (repo *GitRepo) GetRepoStateHash() (string, error) {
	stateSummary, err := repo.runGitCommand("show-ref")
	return fmt.Sprintf("%x", sha1.Sum([]byte(stateSummary))), err
}

// GetUserName returns the name the the user has used to configure git
func (repo *GitRepo) GetUserName() (string, error) {
	return repo.runGitCommand("config", "user.name")
}

// GetUserEmail returns the email address that the user has used to configure git.
func (repo *GitRepo) GetUserEmail() (string, error) {
	return repo.runGitCommand("config", "user.email")
}

// GetCoreEditor returns the name of the editor that the user has used to configure git.
func (repo *GitRepo) GetCoreEditor() (string, error) {
	return repo.runGitCommand("var", "GIT_EDITOR")
}

// PullRefs pull git refs from a remote
func (repo *GitRepo) PullRefs(remote string, refPattern string) error {
	fetchRefSpec := fmt.Sprintf("+%s:%s", refPattern, refPattern)
	_, err := repo.runGitCommand("fetch", remote, fetchRefSpec)

	// TODO: merge new data

	return err
}

// PushRefs push git refs to a remote
func (repo *GitRepo) PushRefs(remote string, refPattern string) error {
	// The push is liable to fail if the user forgot to do a pull first, so
	// we treat errors as user errors rather than fatal errors.
	_, err := repo.runGitCommand("push", remote, refPattern)
	if err != nil {
		return fmt.Errorf("failed to push to the remote '%s': %v", remote, err)
	}
	return nil
}

// StoreData will store arbitrary data and return the corresponding hash
func (repo *GitRepo) StoreData(data []byte) (util.Hash, error) {
	var stdin = bytes.NewReader(data)

	stdout, err := repo.runGitCommandWithStdin(stdin, "hash-object", "--stdin", "-w")

	return util.Hash(stdout), err
}

// StoreTree will store a mapping key-->Hash as a Git tree
func (repo *GitRepo) StoreTree(mapping map[string]util.Hash) (util.Hash, error) {
	var buffer bytes.Buffer

	for key, hash := range mapping {
		buffer.WriteString(fmt.Sprintf("100644 blob %s\t%s\n", hash, key))
	}

	stdout, err := repo.runGitCommandWithStdin(&buffer, "mktree")
	if err != nil {
		return "", err
	}

	return util.Hash(stdout), nil
}

// StoreCommit will store a Git commit with the given Git tree
func (repo *GitRepo) StoreCommit(treeHash util.Hash) (util.Hash, error) {
	stdout, err := repo.runGitCommand("commit-tree", string(treeHash))

	if err != nil {
		return "", err
	}

	return util.Hash(stdout), nil
}

// StoreCommitWithParent will store a Git commit with the given Git tree
func (repo *GitRepo) StoreCommitWithParent(treeHash util.Hash, parent util.Hash) (util.Hash, error) {
	stdout, err := repo.runGitCommand("commit-tree", string(treeHash),
		"-p", string(parent))

	if err != nil {
		return "", err
	}

	return util.Hash(stdout), nil
}

// UpdateRef will create or update a Git reference
func (repo *GitRepo) UpdateRef(ref string, hash util.Hash) error {
	_, err := repo.runGitCommand("update-ref", ref, string(hash))

	return err
}