Add agit flow support in gitea (#14295)

* feature: add agit flow support

ref: https://git-repo.info/en/2020/03/agit-flow-and-git-repo/

example:

```Bash
git checkout -b test
echo "test" >> README.md
git commit -m "test"
git push origin HEAD:refs/for/master -o topic=test
```

Signed-off-by: a1012112796 <1012112796@qq.com>

* fix lint

* simplify code add fix some nits

* update merge help message

* Apply suggestions from code review. Thanks @jiangxin

* add forced-update message

* fix lint

* splite writePktLine

* add refs/for/<target-branch>/<topic-branch> support also

* Add test code add fix api

* fix lint

* fix test

* skip test if git version < 2.29

* try test with git 2.30.1

* fix permission check bug

* fix some nit

* logic implify and test code update

* fix bug

* apply suggestions from code review

* prepare for merge

Signed-off-by: Andrew Thornton <art27@cantab.net>

* fix permission check bug

- test code update
- apply suggestions from code review @zeripath

Signed-off-by: a1012112796 <1012112796@qq.com>

* fix bug when target branch isn't exist

* prevent some special push and fix some nits

* fix lint

* try splite

* Apply suggestions from code review

- fix permission check
- handle user rename

* fix version negotiation

* remane

* fix template

* handle empty repo

* ui: fix  branch link under the title

* fix nits

Co-authored-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

modules/convert/pull.go

@@ -95,7 +95,25 @@ func ToAPIPullRequest(pr *models.PullRequest) *api.PullRequest {
 		}
 	}
 
-	if pr.HeadRepo != nil {
+	if pr.Flow == models.PullRequestFlowAGit {
+		gitRepo, err := git.OpenRepository(pr.BaseRepo.RepoPath())
+		if err != nil {
+			log.Error("OpenRepository[%s]: %v", pr.GetGitRefName(), err)
+			return nil
+		}
+		defer gitRepo.Close()
+
+		apiPullRequest.Head.Sha, err = gitRepo.GetRefCommitID(pr.GetGitRefName())
+		if err != nil {
+			log.Error("GetRefCommitID[%s]: %v", pr.GetGitRefName(), err)
+			return nil
+		}
+		apiPullRequest.Head.RepoID = pr.BaseRepoID
+		apiPullRequest.Head.Repository = apiPullRequest.Base.Repository
+		apiPullRequest.Head.Name = ""
+	}
+
+	if pr.HeadRepo != nil && pr.Flow == models.PullRequestFlowGithub {
 		apiPullRequest.Head.RepoID = pr.HeadRepo.ID
 		apiPullRequest.Head.Repository = ToRepo(pr.HeadRepo, models.AccessModeNone)
 

modules/git/git.go

@@ -37,6 +37,9 @@ var (
 
 	// will be checked on Init
 	goVersionLessThan115 = true
+
+	// SupportProcReceive version >= 2.29.0
+	SupportProcReceive bool
 )
 
 // LocalVersion returns current Git version from shell.
@@ -183,6 +186,19 @@ func Init(ctx context.Context) error {
 		}
 	}
 
+	if CheckGitVersionAtLeast("2.29") == nil {
+		// set support for AGit flow
+		if err := checkAndAddConfig("receive.procReceiveRefs", "refs/for"); err != nil {
+			return err
+		}
+		SupportProcReceive = true
+	} else {
+		if err := checkAndRemoveConfig("receive.procReceiveRefs", "refs/for"); err != nil {
+			return err
+		}
+		SupportProcReceive = false
+	}
+
 	if runtime.GOOS == "windows" {
 		if err := checkAndSetConfig("core.longpaths", "true", true); err != nil {
 			return err
@@ -232,6 +248,51 @@ func checkAndSetConfig(key, defaultValue string, forceToDefault bool) error {
 	return nil
 }
 
+func checkAndAddConfig(key, value string) error {
+	_, stderr, err := process.GetManager().Exec("git.Init(get setting)", GitExecutable, "config", "--get", key, value)
+	if err != nil {
+		perr, ok := err.(*process.Error)
+		if !ok {
+			return fmt.Errorf("Failed to get git %s(%v) errType %T: %s", key, err, err, stderr)
+		}
+		eerr, ok := perr.Err.(*exec.ExitError)
+		if !ok || eerr.ExitCode() != 1 {
+			return fmt.Errorf("Failed to get git %s(%v) errType %T: %s", key, err, err, stderr)
+		}
+		if eerr.ExitCode() == 1 {
+			if _, stderr, err = process.GetManager().Exec(fmt.Sprintf("git.Init(set %s)", key), "git", "config", "--global", "--add", key, value); err != nil {
+				return fmt.Errorf("Failed to set git %s(%s): %s", key, err, stderr)
+			}
+			return nil
+		}
+	}
+
+	return nil
+}
+
+func checkAndRemoveConfig(key, value string) error {
+	_, stderr, err := process.GetManager().Exec("git.Init(get setting)", GitExecutable, "config", "--get", key, value)
+	if err != nil {
+		perr, ok := err.(*process.Error)
+		if !ok {
+			return fmt.Errorf("Failed to get git %s(%v) errType %T: %s", key, err, err, stderr)
+		}
+		eerr, ok := perr.Err.(*exec.ExitError)
+		if !ok || eerr.ExitCode() != 1 {
+			return fmt.Errorf("Failed to get git %s(%v) errType %T: %s", key, err, err, stderr)
+		}
+		if eerr.ExitCode() == 1 {
+			return nil
+		}
+	}
+
+	if _, stderr, err = process.GetManager().Exec(fmt.Sprintf("git.Init(set %s)", key), "git", "config", "--global", "--unset-all", key, value); err != nil {
+		return fmt.Errorf("Failed to set git %s(%s): %s", key, err, stderr)
+	}
+
+	return nil
+}
+
 // Fsck verifies the connectivity and validity of the objects in the database
 func Fsck(ctx context.Context, repoPath string, timeout time.Duration, args ...string) error {
 	// Make sure timeout makes sense.

modules/git/repo_branch.go

@@ -13,6 +13,14 @@ import (
 // BranchPrefix base dir of the branch information file store on git
 const BranchPrefix = "refs/heads/"
 
+// AGit Flow
+
+// PullRequestPrefix sepcial ref to create a pull request: refs/for/<targe-branch>/<topic-branch>
+// or refs/for/<targe-branch> -o topic='<topic-branch>'
+const PullRequestPrefix = "refs/for/"
+
+// TODO: /refs/for-review for suggest change interface
+
 // IsReferenceExist returns true if given reference exists in the repository.
 func IsReferenceExist(repoPath, name string) bool {
 	_, err := NewCommand("show-ref", "--verify", "--", name).RunInDir(repoPath)

modules/private/hook.go

@@ -6,6 +6,7 @@ package private
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -56,6 +57,7 @@ type HookOptions struct {
 	GitPushOptions                  GitPushOptions
 	PullRequestID                   int64
 	IsDeployKey                     bool
+	IsWiki                          bool
 }
 
 // SSHLogOption ssh log options
@@ -79,6 +81,23 @@ type HookPostReceiveBranchResult struct {
 	URL     string
 }
 
+// HockProcReceiveResult represents an individual result from ProcReceive
+type HockProcReceiveResult struct {
+	Results []HockProcReceiveRefResult
+	Err     string
+}
+
+// HockProcReceiveRefResult represents an individual result from ProcReceive
+type HockProcReceiveRefResult struct {
+	OldOID       string
+	NewOID       string
+	Ref          string
+	OriginalRef  string
+	IsForcePush  bool
+	IsNotMatched bool
+	Err          string
+}
+
 // HookPreReceive check whether the provided commits are allowed
 func HookPreReceive(ctx context.Context, ownerName, repoName string, opts HookOptions) (int, string) {
 	reqURL := setting.LocalURL + fmt.Sprintf("api/internal/hook/pre-receive/%s/%s",
@@ -130,6 +149,33 @@ func HookPostReceive(ctx context.Context, ownerName, repoName string, opts HookO
 	return res, ""
 }
 
+// HookProcReceive proc-receive hook
+func HookProcReceive(ctx context.Context, ownerName, repoName string, opts HookOptions) (*HockProcReceiveResult, error) {
+	reqURL := setting.LocalURL + fmt.Sprintf("api/internal/hook/proc-receive/%s/%s",
+		url.PathEscape(ownerName),
+		url.PathEscape(repoName),
+	)
+
+	req := newInternalRequest(ctx, reqURL, "POST")
+	req = req.Header("Content-Type", "application/json")
+	req.SetTimeout(60*time.Second, time.Duration(60+len(opts.OldCommitIDs))*time.Second)
+	jsonBytes, _ := json.Marshal(opts)
+	req.Body(jsonBytes)
+	resp, err := req.Response()
+	if err != nil {
+		return nil, fmt.Errorf("Unable to contact gitea: %v", err.Error())
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, errors.New(decodeJSONError(resp).Err)
+	}
+	res := &HockProcReceiveResult{}
+	_ = json.NewDecoder(resp.Body).Decode(res)
+
+	return res, nil
+}
+
 // SetDefaultBranch will set the default branch to the provided branch for the provided repository
 func SetDefaultBranch(ctx context.Context, ownerName, repoName, branch string) error {
 	reqURL := setting.LocalURL + fmt.Sprintf("api/internal/hook/set-default-branch/%s/%s/%s",

modules/repository/hooks.go

@@ -12,6 +12,7 @@ import (
 	"path/filepath"
 
 	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
@@ -75,6 +76,14 @@ done
 		fmt.Sprintf("#!/usr/bin/env %s\n%s hook --config=%s update $1 $2 $3\n", setting.ScriptType, util.ShellEscape(setting.AppPath), util.ShellEscape(setting.CustomConf)),
 		fmt.Sprintf("#!/usr/bin/env %s\n%s hook --config=%s post-receive\n", setting.ScriptType, util.ShellEscape(setting.AppPath), util.ShellEscape(setting.CustomConf)),
 	}
+
+	if git.SupportProcReceive {
+		hookNames = append(hookNames, "proc-receive")
+		hookTpls = append(hookTpls,
+			fmt.Sprintf("#!/usr/bin/env %s\n%s hook --config=%s proc-receive\n", setting.ScriptType, util.ShellEscape(setting.AppPath), util.ShellEscape(setting.CustomConf)))
+		giteaHookTpls = append(giteaHookTpls, "")
+	}
+
 	return
 }