Also sync DB branches on push if necessary (#28361)

Fix #28056 

This PR will check whether the repo has zero branch when pushing a
branch. If that, it means this repository hasn't been synced.

The reason caused that is after user upgrade from v1.20 -> v1.21, he
just push branches without visit the repository user interface. Because
all repositories routers will check whether a branches sync is necessary
but push has not such check.

For every repository, it has two states, synced or not synced. If there
is zero branch for a repository, then it will be assumed as non-sync
state. Otherwise, it's synced state. So if we think it's synced, we just
need to update branch/insert new branch. Otherwise do a full sync. So
that, for every push, there will be almost no extra load added. It's
high performance than yours.

For the implementation, we in fact will try to update the branch first,
if updated success with affect records > 0, then all are done. Because
that means the branch has been in the database. If no record is
affected, that means the branch does not exist in database. So there are
two possibilities. One is this is a new branch, then we just need to
insert the record. Another is the branches haven't been synced, then we
need to sync all the branches into database.

2 files changed, 66 insertions, 36 deletions

diff --git a/services/repository/branch.go b/services/repository/branch.go
index 735fa1a756..6dc286675f 100644
--- a/services/repository/branch.go
+++ b/services/repository/branch.go
@@ -20,6 +20,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/queue"
 	repo_module "code.gitea.io/gitea/modules/repository"
+	"code.gitea.io/gitea/modules/timeutil"
 	"code.gitea.io/gitea/modules/util"
 	notify_service "code.gitea.io/gitea/services/notify"
 	files_service "code.gitea.io/gitea/services/repository/files"
@@ -28,35 +29,13 @@ import (
 )
 
 // CreateNewBranch creates a new repository branch
-func CreateNewBranch(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, oldBranchName, branchName string) (err error) {
-	err = repo.MustNotBeArchived()
+func CreateNewBranch(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, gitRepo *git.Repository, oldBranchName, branchName string) (err error) {
+	branch, err := git_model.GetBranch(ctx, repo.ID, oldBranchName)
 	if err != nil {
 		return err
 	}
 
-	// Check if branch name can be used
-	if err := checkBranchName(ctx, repo, branchName); err != nil {
-		return err
-	}
-
-	if !git.IsBranchExist(ctx, repo.RepoPath(), oldBranchName) {
-		return git_model.ErrBranchNotExist{
-			BranchName: oldBranchName,
-		}
-	}
-
-	if err := git.Push(ctx, repo.RepoPath(), git.PushOptions{
-		Remote: repo.RepoPath(),
-		Branch: fmt.Sprintf("%s%s:%s%s", git.BranchPrefix, oldBranchName, git.BranchPrefix, branchName),
-		Env:    repo_module.PushingEnvironment(doer, repo),
-	}); err != nil {
-		if git.IsErrPushOutOfDate(err) || git.IsErrPushRejected(err) {
-			return err
-		}
-		return fmt.Errorf("push: %w", err)
-	}
-
-	return nil
+	return CreateNewBranchFromCommit(ctx, doer, repo, gitRepo, branch.CommitID, branchName)
 }
 
 // Branch contains the branch information
@@ -249,8 +228,49 @@ func checkBranchName(ctx context.Context, repo *repo_model.Repository, name stri
 	return err
 }
 
+// syncBranchToDB sync the branch information in the database. It will try to update the branch first,
+// if updated success with affect records > 0, then all are done. Because that means the branch has been in the database.
+// If no record is affected, that means the branch does not exist in database. So there are two possibilities.
+// One is this is a new branch, then we just need to insert the record. Another is the branches haven't been synced,
+// then we need to sync all the branches into database.
+func syncBranchToDB(ctx context.Context, repoID, pusherID int64, branchName string, commit *git.Commit) error {
+	cnt, err := git_model.UpdateBranch(ctx, repoID, pusherID, branchName, commit)
+	if err != nil {
+		return fmt.Errorf("git_model.UpdateBranch %d:%s failed: %v", repoID, branchName, err)
+	}
+	if cnt > 0 { // This means branch does exist, so it's a normal update. It also means the branch has been synced.
+		return nil
+	}
+
+	// if user haven't visit UI but directly push to a branch after upgrading from 1.20 -> 1.21,
+	// we cannot simply insert the branch but need to check we have branches or not
+	hasBranch, err := db.Exist[git_model.Branch](ctx, git_model.FindBranchOptions{
+		RepoID:          repoID,
+		IsDeletedBranch: util.OptionalBoolFalse,
+	}.ToConds())
+	if err != nil {
+		return err
+	}
+	if !hasBranch {
+		if _, err = repo_module.SyncRepoBranches(ctx, repoID, pusherID); err != nil {
+			return fmt.Errorf("repo_module.SyncRepoBranches %d:%s failed: %v", repoID, branchName, err)
+		}
+		return nil
+	}
+
+	// if database have branches but not this branch, it means this is a new branch
+	return db.Insert(ctx, &git_model.Branch{
+		RepoID:        repoID,
+		Name:          branchName,
+		CommitID:      commit.ID.String(),
+		CommitMessage: commit.Summary(),
+		PusherID:      pusherID,
+		CommitTime:    timeutil.TimeStamp(commit.Committer.When.Unix()),
+	})
+}
+
 // CreateNewBranchFromCommit creates a new repository branch
-func CreateNewBranchFromCommit(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, commit, branchName string) (err error) {
+func CreateNewBranchFromCommit(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, gitRepo *git.Repository, commitID, branchName string) (err error) {
 	err = repo.MustNotBeArchived()
 	if err != nil {
 		return err
@@ -261,18 +281,28 @@ func CreateNewBranchFromCommit(ctx context.Context, doer *user_model.User, repo
 		return err
 	}
 
-	if err := git.Push(ctx, repo.RepoPath(), git.PushOptions{
-		Remote: repo.RepoPath(),
-		Branch: fmt.Sprintf("%s:%s%s", commit, git.BranchPrefix, branchName),
-		Env:    repo_module.PushingEnvironment(doer, repo),
-	}); err != nil {
-		if git.IsErrPushOutOfDate(err) || git.IsErrPushRejected(err) {
+	return db.WithTx(ctx, func(ctx context.Context) error {
+		commit, err := gitRepo.GetCommit(commitID)
+		if err != nil {
+			return err
+		}
+		// database operation should be done before git operation so that we can rollback if git operation failed
+		if err := syncBranchToDB(ctx, repo.ID, doer.ID, branchName, commit); err != nil {
 			return err
 		}
-		return fmt.Errorf("push: %w", err)
-	}
 
-	return nil
+		if err := git.Push(ctx, repo.RepoPath(), git.PushOptions{
+			Remote: repo.RepoPath(),
+			Branch: fmt.Sprintf("%s:%s%s", commitID, git.BranchPrefix, branchName),
+			Env:    repo_module.PushingEnvironment(doer, repo),
+		}); err != nil {
+			if git.IsErrPushOutOfDate(err) || git.IsErrPushRejected(err) {
+				return err
+			}
+			return fmt.Errorf("push: %w", err)
+		}
+		return nil
+	})
 }
 
 // RenameBranch rename a branch
diff --git a/services/repository/push.go b/services/repository/push.go
index 391c8ad4ca..b5388834c0 100644
--- a/services/repository/push.go
+++ b/services/repository/push.go
@@ -259,7 +259,7 @@ func pushUpdates(optsList []*repo_module.PushUpdateOptions) error {
 					commits.Commits = commits.Commits[:setting.UI.FeedMaxCommitNum]
 				}
 
-				if err = git_model.UpdateBranch(ctx, repo.ID, opts.PusherID, branch, newCommit); err != nil {
+				if err = syncBranchToDB(ctx, repo.ID, opts.PusherID, branch, newCommit); err != nil {
 					return fmt.Errorf("git_model.UpdateBranch %s:%s failed: %v", repo.FullName(), branch, err)
 				}