forgejo/services/pull/temp_repo.go
Adam Majer cbf923e87b
Abstract hash function usage (#28138)
Refactor Hash interfaces and centralize hash function. This will allow
easier introduction of different hash function later on.

This forms the "no-op" part of the SHA256 enablement patch.
2023-12-13 21:02:00 +00:00

201 lines
8.3 KiB
Go

// Copyright 2019 The Gitea Authors.
// All rights reserved.
// SPDX-License-Identifier: MIT
package pull
import (
"context"
"fmt"
"os"
"path/filepath"
"strings"
git_model "code.gitea.io/gitea/models/git"
issues_model "code.gitea.io/gitea/models/issues"
repo_model "code.gitea.io/gitea/models/repo"
"code.gitea.io/gitea/modules/git"
"code.gitea.io/gitea/modules/log"
repo_module "code.gitea.io/gitea/modules/repository"
)
// Temporary repos created here use standard branch names to help simplify
// merging code
const (
baseBranch = "base" // equivalent to pr.BaseBranch
trackingBranch = "tracking" // equivalent to pr.HeadBranch
stagingBranch = "staging" // this is used for a working branch
)
type prContext struct {
context.Context
tmpBasePath string
pr *issues_model.PullRequest
outbuf *strings.Builder // we keep these around to help reduce needless buffer recreation,
errbuf *strings.Builder // any use should be preceded by a Reset and preferably after use
}
func (ctx *prContext) RunOpts() *git.RunOpts {
ctx.outbuf.Reset()
ctx.errbuf.Reset()
return &git.RunOpts{
Dir: ctx.tmpBasePath,
Stdout: ctx.outbuf,
Stderr: ctx.errbuf,
}
}
// createTemporaryRepoForPR creates a temporary repo with "base" for pr.BaseBranch and "tracking" for pr.HeadBranch
// it also create a second base branch called "original_base"
func createTemporaryRepoForPR(ctx context.Context, pr *issues_model.PullRequest) (prCtx *prContext, cancel context.CancelFunc, err error) {
if err := pr.LoadHeadRepo(ctx); err != nil {
log.Error("%-v LoadHeadRepo: %v", pr, err)
return nil, nil, fmt.Errorf("%v LoadHeadRepo: %w", pr, err)
} else if pr.HeadRepo == nil {
log.Error("%-v HeadRepo %d does not exist", pr, pr.HeadRepoID)
return nil, nil, &repo_model.ErrRepoNotExist{
ID: pr.HeadRepoID,
}
} else if err := pr.LoadBaseRepo(ctx); err != nil {
log.Error("%-v LoadBaseRepo: %v", pr, err)
return nil, nil, fmt.Errorf("%v LoadBaseRepo: %w", pr, err)
} else if pr.BaseRepo == nil {
log.Error("%-v BaseRepo %d does not exist", pr, pr.BaseRepoID)
return nil, nil, &repo_model.ErrRepoNotExist{
ID: pr.BaseRepoID,
}
} else if err := pr.HeadRepo.LoadOwner(ctx); err != nil {
log.Error("%-v HeadRepo.LoadOwner: %v", pr, err)
return nil, nil, fmt.Errorf("%v HeadRepo.LoadOwner: %w", pr, err)
} else if err := pr.BaseRepo.LoadOwner(ctx); err != nil {
log.Error("%-v BaseRepo.LoadOwner: %v", pr, err)
return nil, nil, fmt.Errorf("%v BaseRepo.LoadOwner: %w", pr, err)
}
// Clone base repo.
tmpBasePath, err := repo_module.CreateTemporaryPath("pull")
if err != nil {
log.Error("CreateTemporaryPath[%-v]: %v", pr, err)
return nil, nil, err
}
prCtx = &prContext{
Context: ctx,
tmpBasePath: tmpBasePath,
pr: pr,
outbuf: &strings.Builder{},
errbuf: &strings.Builder{},
}
cancel = func() {
if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
log.Error("Error whilst removing removing temporary repo for %-v: %v", pr, err)
}
}
baseRepoPath := pr.BaseRepo.RepoPath()
headRepoPath := pr.HeadRepo.RepoPath()
objectFormat, err := git.GetObjectFormatOfRepo(ctx, baseRepoPath)
if err != nil {
log.Error("Unable to fetch ObjectFormat of repository %s: %v", baseRepoPath, err)
cancel()
return nil, nil, err
}
if err := git.InitRepository(ctx, tmpBasePath, false, objectFormat); err != nil {
log.Error("Unable to init tmpBasePath for %-v: %v", pr, err)
cancel()
return nil, nil, err
}
remoteRepoName := "head_repo"
baseBranch := "base"
fetchArgs := git.TrustedCmdArgs{"--no-tags"}
if git.CheckGitVersionAtLeast("2.25.0") == nil {
// Writing the commit graph can be slow and is not needed here
fetchArgs = append(fetchArgs, "--no-write-commit-graph")
}
// addCacheRepo adds git alternatives for the cacheRepoPath in the repoPath
addCacheRepo := func(repoPath, cacheRepoPath string) error {
p := filepath.Join(repoPath, ".git", "objects", "info", "alternates")
f, err := os.OpenFile(p, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o600)
if err != nil {
log.Error("Could not create .git/objects/info/alternates file in %s: %v", repoPath, err)
return err
}
defer f.Close()
data := filepath.Join(cacheRepoPath, "objects")
if _, err := fmt.Fprintln(f, data); err != nil {
log.Error("Could not write to .git/objects/info/alternates file in %s: %v", repoPath, err)
return err
}
return nil
}
// Add head repo remote.
if err := addCacheRepo(tmpBasePath, baseRepoPath); err != nil {
log.Error("%-v Unable to add base repository to temporary repo [%s -> %s]: %v", pr, pr.BaseRepo.FullName(), tmpBasePath, err)
cancel()
return nil, nil, fmt.Errorf("Unable to add base repository to temporary repo [%s -> tmpBasePath]: %w", pr.BaseRepo.FullName(), err)
}
if err := git.NewCommand(ctx, "remote", "add", "-t").AddDynamicArguments(pr.BaseBranch).AddArguments("-m").AddDynamicArguments(pr.BaseBranch).AddDynamicArguments("origin", baseRepoPath).
Run(prCtx.RunOpts()); err != nil {
log.Error("%-v Unable to add base repository as origin [%s -> %s]: %v\n%s\n%s", pr, pr.BaseRepo.FullName(), tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
cancel()
return nil, nil, fmt.Errorf("Unable to add base repository as origin [%s -> tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), err, prCtx.outbuf.String(), prCtx.errbuf.String())
}
if err := git.NewCommand(ctx, "fetch", "origin").AddArguments(fetchArgs...).AddDashesAndList(pr.BaseBranch+":"+baseBranch, pr.BaseBranch+":original_"+baseBranch).
Run(prCtx.RunOpts()); err != nil {
log.Error("%-v Unable to fetch origin base branch [%s:%s -> base, original_base in %s]: %v:\n%s\n%s", pr, pr.BaseRepo.FullName(), pr.BaseBranch, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
cancel()
return nil, nil, fmt.Errorf("Unable to fetch origin base branch [%s:%s -> base, original_base in tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), pr.BaseBranch, err, prCtx.outbuf.String(), prCtx.errbuf.String())
}
if err := git.NewCommand(ctx, "symbolic-ref").AddDynamicArguments("HEAD", git.BranchPrefix+baseBranch).
Run(prCtx.RunOpts()); err != nil {
log.Error("%-v Unable to set HEAD as base branch in [%s]: %v\n%s\n%s", pr, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
cancel()
return nil, nil, fmt.Errorf("Unable to set HEAD as base branch in tmpBasePath: %w\n%s\n%s", err, prCtx.outbuf.String(), prCtx.errbuf.String())
}
if err := addCacheRepo(tmpBasePath, headRepoPath); err != nil {
log.Error("%-v Unable to add head repository to temporary repo [%s -> %s]: %v", pr, pr.HeadRepo.FullName(), tmpBasePath, err)
cancel()
return nil, nil, fmt.Errorf("Unable to add head base repository to temporary repo [%s -> tmpBasePath]: %w", pr.HeadRepo.FullName(), err)
}
if err := git.NewCommand(ctx, "remote", "add").AddDynamicArguments(remoteRepoName, headRepoPath).
Run(prCtx.RunOpts()); err != nil {
log.Error("%-v Unable to add head repository as head_repo [%s -> %s]: %v\n%s\n%s", pr, pr.HeadRepo.FullName(), tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
cancel()
return nil, nil, fmt.Errorf("Unable to add head repository as head_repo [%s -> tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), err, prCtx.outbuf.String(), prCtx.errbuf.String())
}
trackingBranch := "tracking"
// Fetch head branch
var headBranch string
if pr.Flow == issues_model.PullRequestFlowGithub {
headBranch = git.BranchPrefix + pr.HeadBranch
} else if len(pr.HeadCommitID) == objectFormat.FullLength() { // for not created pull request
headBranch = pr.HeadCommitID
} else {
headBranch = pr.GetGitRefName()
}
if err := git.NewCommand(ctx, "fetch").AddArguments(fetchArgs...).AddDynamicArguments(remoteRepoName, headBranch+":"+trackingBranch).
Run(prCtx.RunOpts()); err != nil {
cancel()
if !git.IsBranchExist(ctx, pr.HeadRepo.RepoPath(), pr.HeadBranch) {
return nil, nil, git_model.ErrBranchNotExist{
BranchName: pr.HeadBranch,
}
}
log.Error("%-v Unable to fetch head_repo head branch [%s:%s -> tracking in %s]: %v:\n%s\n%s", pr, pr.HeadRepo.FullName(), pr.HeadBranch, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
return nil, nil, fmt.Errorf("Unable to fetch head_repo head branch [%s:%s -> tracking in tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), headBranch, err, prCtx.outbuf.String(), prCtx.errbuf.String())
}
prCtx.outbuf.Reset()
prCtx.errbuf.Reset()
return prCtx, cancel, nil
}