gitea/services/repository/files/temp_repo.go
Mihir Joshi b8270240bf
Fix reverting a merge commit failing (#28794)
Fixes #22236

---
Error occurring currently while trying to revert commit using read-tree
-m approach:
> 2022/12/26 16:04:43 ...rvices/pull/patch.go:240:AttemptThreeWayMerge()
[E] [63a9c61a] Unable to run read-tree -m! Error: exit status 128 -
fatal: this operation must be run in a work tree
> 	 - fatal: this operation must be run in a work tree

We need to clone a non-bare repository for `git read-tree -m` to work.

bb371aee6e
adds support to create a non-bare cloned temporary upload repository.

After cloning a non-bare temporary upload repository, we [set default
index](https://github.com/go-gitea/gitea/blob/main/services/repository/files/cherry_pick.go#L37)
(`git read-tree HEAD`).
This operation ends up resetting the git index file (see investigation
details below), due to which, we need to call `git update-index
--refresh` afterward.


Here's the diff of the index file before and after we execute
SetDefaultIndex: https://www.diffchecker.com/hyOP3eJy/

Notice the **ctime**, **mtime** are set to 0 after SetDefaultIndex.

You can reproduce the same behavior using these steps:
```bash
$ git clone https://try.gitea.io/me-heer/test.git -s -b main
$ cd test
$ git read-tree HEAD
$ git read-tree -m 1f085d7ed8 1f085d7ed8 9933caed00
error: Entry '1' not uptodate. Cannot merge.
```

After which, we can fix like this:
```
$ git update-index --refresh
$ git read-tree -m 1f085d7ed8 1f085d7ed8 9933caed00
```
2024-01-16 15:06:51 +00:00

400 lines
15 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package files
import (
"bytes"
"context"
"fmt"
"io"
"os"
"regexp"
"strings"
"time"
"code.gitea.io/gitea/models"
repo_model "code.gitea.io/gitea/models/repo"
user_model "code.gitea.io/gitea/models/user"
"code.gitea.io/gitea/modules/git"
"code.gitea.io/gitea/modules/log"
repo_module "code.gitea.io/gitea/modules/repository"
"code.gitea.io/gitea/modules/setting"
asymkey_service "code.gitea.io/gitea/services/asymkey"
"code.gitea.io/gitea/services/gitdiff"
)
// TemporaryUploadRepository is a type to wrap our upload repositories as a shallow clone
type TemporaryUploadRepository struct {
ctx context.Context
repo *repo_model.Repository
gitRepo *git.Repository
basePath string
}
// NewTemporaryUploadRepository creates a new temporary upload repository
func NewTemporaryUploadRepository(ctx context.Context, repo *repo_model.Repository) (*TemporaryUploadRepository, error) {
basePath, err := repo_module.CreateTemporaryPath("upload")
if err != nil {
return nil, err
}
t := &TemporaryUploadRepository{ctx: ctx, repo: repo, basePath: basePath}
return t, nil
}
// Close the repository cleaning up all files
func (t *TemporaryUploadRepository) Close() {
defer t.gitRepo.Close()
if err := repo_module.RemoveTemporaryPath(t.basePath); err != nil {
log.Error("Failed to remove temporary path %s: %v", t.basePath, err)
}
}
// Clone the base repository to our path and set branch as the HEAD
func (t *TemporaryUploadRepository) Clone(branch string, bare bool) error {
cmd := git.NewCommand(t.ctx, "clone", "-s", "-b").AddDynamicArguments(branch, t.repo.RepoPath(), t.basePath)
if bare {
cmd.AddArguments("--bare")
}
if _, _, err := cmd.RunStdString(nil); err != nil {
stderr := err.Error()
if matched, _ := regexp.MatchString(".*Remote branch .* not found in upstream origin.*", stderr); matched {
return git.ErrBranchNotExist{
Name: branch,
}
} else if matched, _ := regexp.MatchString(".* repository .* does not exist.*", stderr); matched {
return repo_model.ErrRepoNotExist{
ID: t.repo.ID,
UID: t.repo.OwnerID,
OwnerName: t.repo.OwnerName,
Name: t.repo.Name,
}
}
return fmt.Errorf("Clone: %w %s", err, stderr)
}
gitRepo, err := git.OpenRepository(t.ctx, t.basePath)
if err != nil {
return err
}
t.gitRepo = gitRepo
return nil
}
// Init the repository
func (t *TemporaryUploadRepository) Init(objectFormatName string) error {
if err := git.InitRepository(t.ctx, t.basePath, false, objectFormatName); err != nil {
return err
}
gitRepo, err := git.OpenRepository(t.ctx, t.basePath)
if err != nil {
return err
}
t.gitRepo = gitRepo
return nil
}
// SetDefaultIndex sets the git index to our HEAD
func (t *TemporaryUploadRepository) SetDefaultIndex() error {
if _, _, err := git.NewCommand(t.ctx, "read-tree", "HEAD").RunStdString(&git.RunOpts{Dir: t.basePath}); err != nil {
return fmt.Errorf("SetDefaultIndex: %w", err)
}
return nil
}
// RefreshIndex looks at the current index and checks to see if merges or updates are needed by checking stat() information.
func (t *TemporaryUploadRepository) RefreshIndex() error {
if _, _, err := git.NewCommand(t.ctx, "update-index", "--refresh").RunStdString(&git.RunOpts{Dir: t.basePath}); err != nil {
return fmt.Errorf("RefreshIndex: %w", err)
}
return nil
}
// LsFiles checks if the given filename arguments are in the index
func (t *TemporaryUploadRepository) LsFiles(filenames ...string) ([]string, error) {
stdOut := new(bytes.Buffer)
stdErr := new(bytes.Buffer)
if err := git.NewCommand(t.ctx, "ls-files", "-z").AddDashesAndList(filenames...).
Run(&git.RunOpts{
Dir: t.basePath,
Stdout: stdOut,
Stderr: stdErr,
}); err != nil {
log.Error("Unable to run git ls-files for temporary repo: %s (%s) Error: %v\nstdout: %s\nstderr: %s", t.repo.FullName(), t.basePath, err, stdOut.String(), stdErr.String())
err = fmt.Errorf("Unable to run git ls-files for temporary repo of: %s Error: %w\nstdout: %s\nstderr: %s", t.repo.FullName(), err, stdOut.String(), stdErr.String())
return nil, err
}
fileList := make([]string, 0, len(filenames))
for _, line := range bytes.Split(stdOut.Bytes(), []byte{'\000'}) {
fileList = append(fileList, string(line))
}
return fileList, nil
}
// RemoveFilesFromIndex removes the given files from the index
func (t *TemporaryUploadRepository) RemoveFilesFromIndex(filenames ...string) error {
stdOut := new(bytes.Buffer)
stdErr := new(bytes.Buffer)
stdIn := new(bytes.Buffer)
for _, file := range filenames {
if file != "" {
stdIn.WriteString("0 0000000000000000000000000000000000000000\t")
stdIn.WriteString(file)
stdIn.WriteByte('\000')
}
}
if err := git.NewCommand(t.ctx, "update-index", "--remove", "-z", "--index-info").
Run(&git.RunOpts{
Dir: t.basePath,
Stdin: stdIn,
Stdout: stdOut,
Stderr: stdErr,
}); err != nil {
log.Error("Unable to update-index for temporary repo: %s (%s) Error: %v\nstdout: %s\nstderr: %s", t.repo.FullName(), t.basePath, err, stdOut.String(), stdErr.String())
return fmt.Errorf("Unable to update-index for temporary repo: %s Error: %w\nstdout: %s\nstderr: %s", t.repo.FullName(), err, stdOut.String(), stdErr.String())
}
return nil
}
// HashObject writes the provided content to the object db and returns its hash
func (t *TemporaryUploadRepository) HashObject(content io.Reader) (string, error) {
stdOut := new(bytes.Buffer)
stdErr := new(bytes.Buffer)
if err := git.NewCommand(t.ctx, "hash-object", "-w", "--stdin").
Run(&git.RunOpts{
Dir: t.basePath,
Stdin: content,
Stdout: stdOut,
Stderr: stdErr,
}); err != nil {
log.Error("Unable to hash-object to temporary repo: %s (%s) Error: %v\nstdout: %s\nstderr: %s", t.repo.FullName(), t.basePath, err, stdOut.String(), stdErr.String())
return "", fmt.Errorf("Unable to hash-object to temporary repo: %s Error: %w\nstdout: %s\nstderr: %s", t.repo.FullName(), err, stdOut.String(), stdErr.String())
}
return strings.TrimSpace(stdOut.String()), nil
}
// AddObjectToIndex adds the provided object hash to the index with the provided mode and path
func (t *TemporaryUploadRepository) AddObjectToIndex(mode, objectHash, objectPath string) error {
if _, _, err := git.NewCommand(t.ctx, "update-index", "--add", "--replace", "--cacheinfo").AddDynamicArguments(mode, objectHash, objectPath).RunStdString(&git.RunOpts{Dir: t.basePath}); err != nil {
stderr := err.Error()
if matched, _ := regexp.MatchString(".*Invalid path '.*", stderr); matched {
return models.ErrFilePathInvalid{
Message: objectPath,
Path: objectPath,
}
}
log.Error("Unable to add object to index: %s %s %s in temporary repo %s(%s) Error: %v", mode, objectHash, objectPath, t.repo.FullName(), t.basePath, err)
return fmt.Errorf("Unable to add object to index at %s in temporary repo %s Error: %w", objectPath, t.repo.FullName(), err)
}
return nil
}
// WriteTree writes the current index as a tree to the object db and returns its hash
func (t *TemporaryUploadRepository) WriteTree() (string, error) {
stdout, _, err := git.NewCommand(t.ctx, "write-tree").RunStdString(&git.RunOpts{Dir: t.basePath})
if err != nil {
log.Error("Unable to write tree in temporary repo: %s(%s): Error: %v", t.repo.FullName(), t.basePath, err)
return "", fmt.Errorf("Unable to write-tree in temporary repo for: %s Error: %w", t.repo.FullName(), err)
}
return strings.TrimSpace(stdout), nil
}
// GetLastCommit gets the last commit ID SHA of the repo
func (t *TemporaryUploadRepository) GetLastCommit() (string, error) {
return t.GetLastCommitByRef("HEAD")
}
// GetLastCommitByRef gets the last commit ID SHA of the repo by ref
func (t *TemporaryUploadRepository) GetLastCommitByRef(ref string) (string, error) {
if ref == "" {
ref = "HEAD"
}
stdout, _, err := git.NewCommand(t.ctx, "rev-parse").AddDynamicArguments(ref).RunStdString(&git.RunOpts{Dir: t.basePath})
if err != nil {
log.Error("Unable to get last ref for %s in temporary repo: %s(%s): Error: %v", ref, t.repo.FullName(), t.basePath, err)
return "", fmt.Errorf("Unable to rev-parse %s in temporary repo for: %s Error: %w", ref, t.repo.FullName(), err)
}
return strings.TrimSpace(stdout), nil
}
// CommitTree creates a commit from a given tree for the user with provided message
func (t *TemporaryUploadRepository) CommitTree(parent string, author, committer *user_model.User, treeHash, message string, signoff bool) (string, error) {
return t.CommitTreeWithDate(parent, author, committer, treeHash, message, signoff, time.Now(), time.Now())
}
// CommitTreeWithDate creates a commit from a given tree for the user with provided message
func (t *TemporaryUploadRepository) CommitTreeWithDate(parent string, author, committer *user_model.User, treeHash, message string, signoff bool, authorDate, committerDate time.Time) (string, error) {
authorSig := author.NewGitSig()
committerSig := committer.NewGitSig()
// Because this may call hooks we should pass in the environment
env := append(os.Environ(),
"GIT_AUTHOR_NAME="+authorSig.Name,
"GIT_AUTHOR_EMAIL="+authorSig.Email,
"GIT_AUTHOR_DATE="+authorDate.Format(time.RFC3339),
"GIT_COMMITTER_DATE="+committerDate.Format(time.RFC3339),
)
messageBytes := new(bytes.Buffer)
_, _ = messageBytes.WriteString(message)
_, _ = messageBytes.WriteString("\n")
cmdCommitTree := git.NewCommand(t.ctx, "commit-tree").AddDynamicArguments(treeHash)
if parent != "" {
cmdCommitTree.AddOptionValues("-p", parent)
}
var sign bool
var keyID string
var signer *git.Signature
if parent != "" {
sign, keyID, signer, _ = asymkey_service.SignCRUDAction(t.ctx, t.repo.RepoPath(), author, t.basePath, parent)
} else {
sign, keyID, signer, _ = asymkey_service.SignInitialCommit(t.ctx, t.repo.RepoPath(), author)
}
if sign {
cmdCommitTree.AddOptionFormat("-S%s", keyID)
if t.repo.GetTrustModel() == repo_model.CommitterTrustModel || t.repo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
if committerSig.Name != authorSig.Name || committerSig.Email != authorSig.Email {
// Add trailers
_, _ = messageBytes.WriteString("\n")
_, _ = messageBytes.WriteString("Co-authored-by: ")
_, _ = messageBytes.WriteString(committerSig.String())
_, _ = messageBytes.WriteString("\n")
_, _ = messageBytes.WriteString("Co-committed-by: ")
_, _ = messageBytes.WriteString(committerSig.String())
_, _ = messageBytes.WriteString("\n")
}
committerSig = signer
}
} else {
cmdCommitTree.AddArguments("--no-gpg-sign")
}
if signoff {
// Signed-off-by
_, _ = messageBytes.WriteString("\n")
_, _ = messageBytes.WriteString("Signed-off-by: ")
_, _ = messageBytes.WriteString(committerSig.String())
}
env = append(env,
"GIT_COMMITTER_NAME="+committerSig.Name,
"GIT_COMMITTER_EMAIL="+committerSig.Email,
)
stdout := new(bytes.Buffer)
stderr := new(bytes.Buffer)
if err := cmdCommitTree.
Run(&git.RunOpts{
Env: env,
Dir: t.basePath,
Stdin: messageBytes,
Stdout: stdout,
Stderr: stderr,
}); err != nil {
log.Error("Unable to commit-tree in temporary repo: %s (%s) Error: %v\nStdout: %s\nStderr: %s",
t.repo.FullName(), t.basePath, err, stdout, stderr)
return "", fmt.Errorf("Unable to commit-tree in temporary repo: %s Error: %w\nStdout: %s\nStderr: %s",
t.repo.FullName(), err, stdout, stderr)
}
return strings.TrimSpace(stdout.String()), nil
}
// Push the provided commitHash to the repository branch by the provided user
func (t *TemporaryUploadRepository) Push(doer *user_model.User, commitHash, branch string) error {
// Because calls hooks we need to pass in the environment
env := repo_module.PushingEnvironment(doer, t.repo)
if err := git.Push(t.ctx, t.basePath, git.PushOptions{
Remote: t.repo.RepoPath(),
Branch: strings.TrimSpace(commitHash) + ":" + git.BranchPrefix + strings.TrimSpace(branch),
Env: env,
}); err != nil {
if git.IsErrPushOutOfDate(err) {
return err
} else if git.IsErrPushRejected(err) {
rejectErr := err.(*git.ErrPushRejected)
log.Info("Unable to push back to repo from temporary repo due to rejection: %s (%s)\nStdout: %s\nStderr: %s\nError: %v",
t.repo.FullName(), t.basePath, rejectErr.StdOut, rejectErr.StdErr, rejectErr.Err)
return err
}
log.Error("Unable to push back to repo from temporary repo: %s (%s)\nError: %v",
t.repo.FullName(), t.basePath, err)
return fmt.Errorf("Unable to push back to repo from temporary repo: %s (%s) Error: %v",
t.repo.FullName(), t.basePath, err)
}
return nil
}
// DiffIndex returns a Diff of the current index to the head
func (t *TemporaryUploadRepository) DiffIndex() (*gitdiff.Diff, error) {
stdoutReader, stdoutWriter, err := os.Pipe()
if err != nil {
log.Error("Unable to open stdout pipe: %v", err)
return nil, fmt.Errorf("Unable to open stdout pipe: %w", err)
}
defer func() {
_ = stdoutReader.Close()
_ = stdoutWriter.Close()
}()
stderr := new(bytes.Buffer)
var diff *gitdiff.Diff
var finalErr error
if err := git.NewCommand(t.ctx, "diff-index", "--src-prefix=\\a/", "--dst-prefix=\\b/", "--cached", "-p", "HEAD").
Run(&git.RunOpts{
Timeout: 30 * time.Second,
Dir: t.basePath,
Stdout: stdoutWriter,
Stderr: stderr,
PipelineFunc: func(ctx context.Context, cancel context.CancelFunc) error {
_ = stdoutWriter.Close()
diff, finalErr = gitdiff.ParsePatch(t.ctx, setting.Git.MaxGitDiffLines, setting.Git.MaxGitDiffLineCharacters, setting.Git.MaxGitDiffFiles, stdoutReader, "")
if finalErr != nil {
log.Error("ParsePatch: %v", finalErr)
cancel()
}
_ = stdoutReader.Close()
return finalErr
},
}); err != nil {
if finalErr != nil {
log.Error("Unable to ParsePatch in temporary repo %s (%s). Error: %v", t.repo.FullName(), t.basePath, finalErr)
return nil, finalErr
}
log.Error("Unable to run diff-index pipeline in temporary repo %s (%s). Error: %v\nStderr: %s",
t.repo.FullName(), t.basePath, err, stderr)
return nil, fmt.Errorf("Unable to run diff-index pipeline in temporary repo %s. Error: %w\nStderr: %s",
t.repo.FullName(), err, stderr)
}
diff.NumFiles, diff.TotalAddition, diff.TotalDeletion, err = git.GetDiffShortStat(t.ctx, t.basePath, git.TrustedCmdArgs{"--cached"}, "HEAD")
if err != nil {
return nil, err
}
return diff, nil
}
// GetBranchCommit Gets the commit object of the given branch
func (t *TemporaryUploadRepository) GetBranchCommit(branch string) (*git.Commit, error) {
if t.gitRepo == nil {
return nil, fmt.Errorf("repository has not been cloned")
}
return t.gitRepo.GetBranchCommit(branch)
}
// GetCommit Gets the commit object of the given commit ID
func (t *TemporaryUploadRepository) GetCommit(commitID string) (*git.Commit, error) {
if t.gitRepo == nil {
return nil, fmt.Errorf("repository has not been cloned")
}
return t.gitRepo.GetCommit(commitID)
}