fix(tibuild-v2): reject commits already tagged with tidbx-style tag

experiments/tibuild-v2/internal/service/impl/hotfix_tidbx.go

@@ -23,6 +23,7 @@ func (s *hotfixsrvc) BumpTagForTidbx(ctx context.Context, p *hotfix.BumpTagForTi
 	// Parse repository owner and name
 	parts := strings.SplitN(p.Repo, "/", 2)
 	if len(parts) != 2 {
+		l.Warn().Msg("Invalid repository format, expected 'owner/repo'")
 		return nil, &hotfix.HTTPError{
 			Code:    http.StatusBadRequest,
 			Message: "invalid repository format, expected 'owner/repo'",
@@ -32,6 +33,7 @@ func (s *hotfixsrvc) BumpTagForTidbx(ctx context.Context, p *hotfix.BumpTagForTi
 
 	// Validate that at least one of branch or commit is provided
 	if p.Branch == nil && p.Commit == nil {
+		l.Warn().Msg("At least one of 'branch' or 'commit' must be provided")
 		return nil, &hotfix.HTTPError{
 			Code:    http.StatusBadRequest,
 			Message: "at least one of 'branch' or 'commit' must be provided",
@@ -41,39 +43,42 @@ func (s *hotfixsrvc) BumpTagForTidbx(ctx context.Context, p *hotfix.BumpTagForTi
 	// Step 1: Verify the branch or commit exists
 	commitSHA, err := s.verifyAndGetCommit(ctx, owner, repo, p.Branch, p.Commit)
 	if err != nil {
+		l.Err(err).Msg("Failed to verify commit")
 		return nil, err
 	}
 
 	l = l.With().Str("commit", commitSHA).Logger()
 	l.Info().Msg("Verified commit exists")
 
-	// Step 2: Compute the tag name
-	tagName, err := s.computeNewTagNameForTidbx(ctx, owner, repo)
+	// Step 2: Compute the tag name (and fail if commit already has a tidbx-style tag)
+	tagName, err := s.computeNewTagNameForTidbx(ctx, owner, repo, commitSHA)
 	if err != nil {
+		l.Err(err).Msg("Failed to compute tag name")
 		return nil, err
 	}
 
 	l = l.With().Str("tag", tagName).Logger()
 	l.Info().Msg("Computed tag name")
 
 	// Step 3: Create the tag with author information
-	tagMessage := fmt.Sprintf("Hot fix tag created by %s", p.Author)
+	tagMessage := fmt.Sprintf("Created hot fix tag on behalf of %s", p.Author)
 	if err := s.createTag(ctx, owner, repo, tagName, commitSHA, tagMessage); err != nil {
+		l.Err(err).Msg("Failed to create tag")
 		return nil, err
 	}
 
 	l.Info().Msg("Successfully created tag")
-
 	return &hotfix.HotfixTagResult{
 		Repo:   p.Repo,
 		Commit: commitSHA,
 		Tag:    tagName,
 	}, nil
 }
 
-// computeNewTagNameForTidbx computes the next tag name based on existing tags.
+// computeNewTagNameForTidbx computes the next tag name based on existing tags,
+// and fails if the provided commit already has a tidbx-style tag.
 // Tags follow the pattern vX.Y.Z-nextgen.YYYYMM.N
-func (s *hotfixsrvc) computeNewTagNameForTidbx(ctx context.Context, owner, repo string) (string, error) {
+func (s *hotfixsrvc) computeNewTagNameForTidbx(ctx context.Context, owner, repo, commitSHA string) (string, error) {
 	// Get all tags from the repository
 	var allTags []*github.RepositoryTag
 	opts := &github.ListOptions{PerPage: 100}
@@ -99,6 +104,17 @@ func (s *hotfixsrvc) computeNewTagNameForTidbx(ctx context.Context, owner, repo
 
 	for _, tag := range allTags {
 		name := tag.GetName()
+
+		// If the tidbx-style tag points to the provided commit, fail fast
+		if pattern.MatchString(name) {
+			if tag.Commit != nil && tag.Commit.SHA != nil && *tag.Commit.SHA == commitSHA {
+				return "", &hotfix.HTTPError{
+					Code:    http.StatusBadRequest,
+					Message: fmt.Sprintf("commit %s already has existing tidbx-style tag: %s", commitSHA, name),
+				}
+			}
+		}
+
 		matches := pattern.FindStringSubmatch(name)
 		if len(matches) == 4 {
 			seq, err := strconv.Atoi(matches[3])

experiments/tibuild-v2/internal/service/impl/hotfix_tidbx_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"io"
 	"net/http"
+	"strings"
 	"testing"
 
 	"github.com/google/go-github/v69/github"
@@ -23,13 +24,15 @@ func newServiceWithClient(client *github.Client) *hotfixsrvc {
 
 func TestComputeNewTagNameForTidbx(t *testing.T) {
 	type testCase struct {
-		name      string
-		pages     [][]string
-		expected  string
-		expectErr bool
-		errCode   int
+		name           string
+		pages          [][]string
+		expected       string
+		taggedCommitSHA string
+		expectErr      bool
+		errCode        int
 	}
 
+	testCommitSHA := "a9814602ed087838d71095efd35bd221ab0bf5a9"
 	cases := []testCase{
 		{
 			name: "LastMonthIncrement",
@@ -85,6 +88,18 @@ func TestComputeNewTagNameForTidbx(t *testing.T) {
 			},
 			expected: "v9.0.0-nextgen.202601.1",
 		},
+		{
+			name: "CommitAlreadyTagged",
+			pages: [][]string{
+				{
+					"v8.5.4-nextgen.202510.1",
+					"v8.5.4-nextgen.202510.2",
+				},
+			},
+			taggedCommitSHA: testCommitSHA,
+			expectErr:      true,
+			errCode:        http.StatusBadRequest,
+		},
 	}
 
 	for _, tc := range cases {
@@ -96,6 +111,10 @@ func TestComputeNewTagNameForTidbx(t *testing.T) {
 				tags := make([]*github.RepositoryTag, len(names))
 				for j, name := range names {
 					tags[j] = &github.RepositoryTag{Name: github.Ptr(name)}
+					// For the CommitAlreadyTagged case, attach the commit SHA to the first tidbx-style tag
+					if j == 0 && tc.taggedCommitSHA != "" && strings.HasPrefix(name, "v") && strings.Contains(name, "-nextgen.") {
+						tags[j].Commit = &github.Commit{SHA: &tc.taggedCommitSHA}
+					}
 				}
 				tagPages = append(tagPages, tags)
 			}
@@ -104,7 +123,7 @@ func TestComputeNewTagNameForTidbx(t *testing.T) {
 			ghClient := github.NewClient(mock.NewMockedHTTPClient(resp))
 			svc := newServiceWithClient(ghClient)
 
-			tag, err := svc.computeNewTagNameForTidbx(context.Background(), "owner", "repo")
+			tag, err := svc.computeNewTagNameForTidbx(context.Background(), "owner", "repo", testCommitSHA)
 			if tc.expectErr {
 				if err == nil {
 					t.Fatalf("expected error, got nil")
@@ -264,3 +283,57 @@ func TestBumpTagForTidbx_PaginationFlow(t *testing.T) {
 		})
 	}
 }
+
+func TestBumpTagForTidbx_FailWhenCommitAlreadyTagged(t *testing.T) {
+	fullRepo := "owner/repo"
+	branch := "main"
+	commit := "abc123"
+
+	// Tags response includes a tidbx-style tag that points to the same commit
+	respTags := mock.WithRequestMatchPages(
+		mock.GetReposTagsByOwnerByRepo,
+		[]*github.RepositoryTag{
+			{Name: github.Ptr("v8.5.4-nextgen.202510.1"), Commit: &github.Commit{SHA: github.Ptr(commit)}},
+			{Name: github.Ptr("v8.5.4-nextgen.202510.2")},
+		},
+	)
+
+	httpClient := mock.NewMockedHTTPClient(
+		respTags,
+		mock.WithRequestMatch(
+			mock.GetReposCommitsByOwnerByRepoByRef,
+			&github.RepositoryCommit{
+				SHA: github.Ptr(commit),
+			},
+		),
+		mock.WithRequestMatch(
+			mock.GetReposBranchesByOwnerByRepoByBranch,
+			&github.Branch{
+				Name: github.Ptr(branch),
+				Commit: &github.RepositoryCommit{
+					SHA: github.Ptr(commit),
+				},
+			},
+		),
+	)
+	svc := newServiceWithClient(github.NewClient(httpClient))
+
+	apiCallPayload := &hotfix.BumpTagForTidbxPayload{
+		Repo:   fullRepo,
+		Author: "tester",
+		Branch: &branch,
+		Commit: &commit,
+	}
+
+	_, err := svc.BumpTagForTidbx(context.Background(), apiCallPayload)
+	if err == nil {
+		t.Fatalf("expected error due to existing tidbx-style tag on commit, got nil")
+	}
+	httpErr, ok := err.(*hotfix.HTTPError)
+	if !ok {
+		t.Fatalf("expected *hotfix.HTTPError, got %T", err)
+	}
+	if httpErr.Code != http.StatusBadRequest {
+		t.Fatalf("expected status %d, got %d", http.StatusBadRequest, httpErr.Code)
+	}
+}