Refactor GetNextResourceIndex to make it work properly with transaction (#21469)

Related:
* #21362

This PR uses a general and stable method to generate resource index (eg:
Issue Index, PR Index)

If the code looks good, I can add more tests

ps: please skip the diff, only have a look at the new code. It's
entirely re-written.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

4 files changed, 21 insertions, 24 deletions

diff --git a/models/issues/issue.go b/models/issues/issue.go
index 49bc229c6b..737b625abc 100644
--- a/models/issues/issue.go
+++ b/models/issues/issue.go
@@ -1064,19 +1064,19 @@ func NewIssueWithIndex(ctx context.Context, doer *user_model.User, opts NewIssue
 
 // NewIssue creates new issue with labels for repository.
 func NewIssue(repo *repo_model.Repository, issue *Issue, labelIDs []int64, uuids []string) (err error) {
-	idx, err := db.GetNextResourceIndex("issue_index", repo.ID)
-	if err != nil {
-		return fmt.Errorf("generate issue index failed: %v", err)
-	}
-
-	issue.Index = idx
-
 	ctx, committer, err := db.TxContext()
 	if err != nil {
 		return err
 	}
 	defer committer.Close()
 
+	idx, err := db.GetNextResourceIndex(ctx, "issue_index", repo.ID)
+	if err != nil {
+		return fmt.Errorf("generate issue index failed: %w", err)
+	}
+
+	issue.Index = idx
+
 	if err = NewIssueWithIndex(ctx, issue.Poster, NewIssueOptions{
 		Repo:        repo,
 		Issue:       issue,
diff --git a/models/issues/issue_index.go b/models/issues/issue_index.go
index 100e814317..f4acc5aa1b 100644
--- a/models/issues/issue_index.go
+++ b/models/issues/issue_index.go
@@ -15,16 +15,12 @@ func RecalculateIssueIndexForRepo(repoID int64) error {
 	}
 	defer committer.Close()
 
-	if err := db.UpsertResourceIndex(ctx, "issue_index", repoID); err != nil {
-		return err
-	}
-
 	var max int64
-	if _, err := db.GetEngine(ctx).Select(" MAX(`index`)").Table("issue").Where("repo_id=?", repoID).Get(&max); err != nil {
+	if _, err = db.GetEngine(ctx).Select(" MAX(`index`)").Table("issue").Where("repo_id=?", repoID).Get(&max); err != nil {
 		return err
 	}
 
-	if _, err := db.GetEngine(ctx).Exec("UPDATE `issue_index` SET max_index=? WHERE group_id=?", max, repoID); err != nil {
+	if err = db.SyncMaxResourceIndex(ctx, "issue_index", repoID, max); err != nil {
 		return err
 	}
 
diff --git a/models/issues/issue_xref_test.go b/models/issues/issue_xref_test.go
index af1c8bc685..0f72fc7ca6 100644
--- a/models/issues/issue_xref_test.go
+++ b/models/issues/issue_xref_test.go
@@ -131,7 +131,11 @@ func testCreateIssue(t *testing.T, repo, doer int64, title, content string, ispu
 	r := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: repo})
 	d := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: doer})
 
-	idx, err := db.GetNextResourceIndex("issue_index", r.ID)
+	ctx, committer, err := db.TxContext()
+	assert.NoError(t, err)
+	defer committer.Close()
+
+	idx, err := db.GetNextResourceIndex(ctx, "issue_index", r.ID)
 	assert.NoError(t, err)
 	i := &issues_model.Issue{
 		RepoID:   r.ID,
@@ -143,9 +147,6 @@ func testCreateIssue(t *testing.T, repo, doer int64, title, content string, ispu
 		Index:    idx,
 	}
 
-	ctx, committer, err := db.TxContext()
-	assert.NoError(t, err)
-	defer committer.Close()
 	err = issues_model.NewIssueWithIndex(ctx, d, issues_model.NewIssueOptions{
 		Repo:  r,
 		Issue: i,
diff --git a/models/issues/pull.go b/models/issues/pull.go
index f96b03445e..69259c269f 100644
--- a/models/issues/pull.go
+++ b/models/issues/pull.go
@@ -490,13 +490,6 @@ func (pr *PullRequest) SetMerged(ctx context.Context) (bool, error) {
 
 // NewPullRequest creates new pull request with labels for repository.
 func NewPullRequest(outerCtx context.Context, repo *repo_model.Repository, issue *Issue, labelIDs []int64, uuids []string, pr *PullRequest) (err error) {
-	idx, err := db.GetNextResourceIndex("issue_index", repo.ID)
-	if err != nil {
-		return fmt.Errorf("generate pull request index failed: %v", err)
-	}
-
-	issue.Index = idx
-
 	ctx, committer, err := db.TxContext()
 	if err != nil {
 		return err
@@ -504,6 +497,13 @@ func NewPullRequest(outerCtx context.Context, repo *repo_model.Repository, issue
 	defer committer.Close()
 	ctx.WithContext(outerCtx)
 
+	idx, err := db.GetNextResourceIndex(ctx, "issue_index", repo.ID)
+	if err != nil {
+		return fmt.Errorf("generate pull request index failed: %v", err)
+	}
+
+	issue.Index = idx
+
 	if err = NewIssueWithIndex(ctx, issue.Poster, NewIssueOptions{
 		Repo:        repo,
 		Issue:       issue,