1package git
2
3import (
4 "context"
5 "errors"
6 "fmt"
7 "io"
8 "os"
9 "os/exec"
10 "strings"
11
12 "github.com/charmbracelet/log"
13 "golang.org/x/sync/errgroup"
14)
15
16// Service is a Git daemon service.
17type Service string
18
19const (
20 // UploadPackService is the upload-pack service.
21 UploadPackService Service = "git-upload-pack"
22 // UploadArchiveService is the upload-archive service.
23 UploadArchiveService Service = "git-upload-archive"
24 // ReceivePackService is the receive-pack service.
25 ReceivePackService Service = "git-receive-pack"
26)
27
28// String returns the string representation of the service.
29func (s Service) String() string {
30 return string(s)
31}
32
33// Name returns the name of the service.
34func (s Service) Name() string {
35 return strings.TrimPrefix(s.String(), "git-")
36}
37
38// Handler is the service handler.
39func (s Service) Handler(ctx context.Context, cmd ServiceCommand) error {
40 switch s {
41 case UploadPackService, UploadArchiveService, ReceivePackService:
42 return gitServiceHandler(ctx, s, cmd)
43 default:
44 return fmt.Errorf("unsupported service: %s", s)
45 }
46}
47
48// ServiceHandler is a git service command handler.
49type ServiceHandler func(ctx context.Context, cmd ServiceCommand) error
50
51// gitServiceHandler is the default service handler using the git binary.
52func gitServiceHandler(ctx context.Context, svc Service, scmd ServiceCommand) error {
53 cmd := exec.CommandContext(ctx, "git", "-c", "uploadpack.allowFilter=true", svc.Name()) // nolint: gosec
54 cmd.Dir = scmd.Dir
55 if len(scmd.Args) > 0 {
56 cmd.Args = append(cmd.Args, scmd.Args...)
57 }
58
59 cmd.Args = append(cmd.Args, ".")
60
61 cmd.Env = os.Environ()
62 if len(scmd.Env) > 0 {
63 cmd.Env = append(cmd.Env, scmd.Env...)
64 }
65
66 if scmd.CmdFunc != nil {
67 scmd.CmdFunc(cmd)
68 }
69
70 var (
71 err error
72 stdin io.WriteCloser
73 stdout io.ReadCloser
74 stderr io.ReadCloser
75 )
76
77 if scmd.Stdin != nil {
78 stdin, err = cmd.StdinPipe()
79 if err != nil {
80 return err
81 }
82 }
83
84 if scmd.Stdout != nil {
85 stdout, err = cmd.StdoutPipe()
86 if err != nil {
87 return err
88 }
89 }
90
91 if scmd.Stderr != nil {
92 stderr, err = cmd.StderrPipe()
93 if err != nil {
94 return err
95 }
96 }
97
98 log.Debugf("git service command in %q: %s", cmd.Dir, cmd.String())
99 if err := cmd.Start(); err != nil {
100 if errors.Is(err, os.ErrNotExist) {
101 return ErrInvalidRepo
102 }
103 return err
104 }
105
106 errg, _ := errgroup.WithContext(ctx)
107
108 // stdin
109 if scmd.Stdin != nil {
110 errg.Go(func() error {
111 defer stdin.Close() // nolint: errcheck
112 _, err := io.Copy(stdin, scmd.Stdin)
113 return err
114 })
115 }
116
117 // stdout
118 if scmd.Stdout != nil {
119 errg.Go(func() error {
120 _, err := io.Copy(scmd.Stdout, stdout)
121 return err
122 })
123 }
124
125 // stderr
126 if scmd.Stderr != nil {
127 errg.Go(func() error {
128 _, erro := io.Copy(scmd.Stderr, stderr)
129 return erro
130 })
131 }
132
133 err = errors.Join(errg.Wait(), cmd.Wait())
134 if err != nil && errors.Is(err, os.ErrNotExist) {
135 return ErrInvalidRepo
136 } else if err != nil {
137 return err
138 }
139
140 return nil
141}
142
143// ServiceCommand is used to run a git service command.
144type ServiceCommand struct {
145 Stdin io.Reader
146 Stdout io.Writer
147 Stderr io.Writer
148 Dir string
149 Env []string
150 Args []string
151
152 // Modifier functions
153 CmdFunc func(*exec.Cmd)
154}
155
156// UploadPack runs the git upload-pack protocol against the provided repo.
157func UploadPack(ctx context.Context, cmd ServiceCommand) error {
158 return gitServiceHandler(ctx, UploadPackService, cmd)
159}
160
161// UploadArchive runs the git upload-archive protocol against the provided repo.
162func UploadArchive(ctx context.Context, cmd ServiceCommand) error {
163 return gitServiceHandler(ctx, UploadArchiveService, cmd)
164}
165
166// ReceivePack runs the git receive-pack protocol against the provided repo.
167func ReceivePack(ctx context.Context, cmd ServiceCommand) error {
168 return gitServiceHandler(ctx, ReceivePackService, cmd)
169}