1

internal/handlers/posts_common.go

@@ -40,7 +40,7 @@ type PostDTO struct {
 	PublishedAt    string          `json:"publishedAt"`
 	UpdatedAt      string          `json:"updatedAt"`
 	CreatedAt      string          `json:"createdAt,omitempty"`
-	Tags           []string        `json:"tags,omitempty"`
+	Tags           []string        `json:"tags"`
 }
 
 type PostListResponse struct {
@@ -310,6 +310,32 @@ func loadPostTagNames(ctx context.Context, pool *pgxpool.Pool, postID uuid.UUID,
 	return names, rows.Err()
 }
 
+func loadPostTagNamesByPostIDs(ctx context.Context, pool *pgxpool.Pool, ids []uuid.UUID, lang string) (map[uuid.UUID][]string, error) {
+	out := make(map[uuid.UUID][]string)
+	if len(ids) == 0 {
+		return out, nil
+	}
+	rows, err := pool.Query(ctx, `
+		SELECT pt.post_id, t.name, COALESCE(t.name_en,''), COALESCE(t.name_ja,''), COALESCE(t.name_ko,''),
+			COALESCE(t.name_vi,''), COALESCE(t.name_id,''), COALESCE(t.name_ms,'')
+		FROM post_tags pt JOIN tags t ON t.id = pt.tag_id
+		WHERE pt.post_id = ANY($1)
+		ORDER BY pt.post_id, t.slug`, ids)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var pid uuid.UUID
+		var name, en, ja, ko, vi, idLoc, ms string
+		if err := rows.Scan(&pid, &name, &en, &ja, &ko, &vi, &idLoc, &ms); err != nil {
+			return nil, err
+		}
+		out[pid] = append(out[pid], tagDisplayName(name, en, ja, ko, vi, idLoc, ms, lang))
+	}
+	return out, rows.Err()
+}
+
 func replacePostTags(ctx context.Context, pool *pgxpool.Pool, postID uuid.UUID, tagSlugs []string) error {
 	_, err := pool.Exec(ctx, `DELETE FROM post_tags WHERE post_id = $1`, postID)
 	if err != nil {

internal/handlers/posts_public.go

@@ -86,6 +86,9 @@ func GetPost(w http.ResponseWriter, r *http.Request) {
 		dto.Attachments = []AttachmentDTO{}
 	}
 	tags, _ := loadPostTagNames(r.Context(), pool, id, requestLangCode(r))
+	if tags == nil {
+		tags = []string{}
+	}
 	dto.Tags = tags
 	writeJSON(w, dto)
 }
@@ -198,6 +201,7 @@ func collectPostRows(r *http.Request, rows pgx.Rows) ([]PostDTO, error) {
 		uid, _ := uuid.Parse(dto.ID)
 		ids = append(ids, uid)
 		dto.Attachments = []AttachmentDTO{}
+		dto.Tags = []string{}
 		list = append(list, dto)
 	}
 	if err := rows.Err(); err != nil {
@@ -207,11 +211,21 @@ func collectPostRows(r *http.Request, rows pgx.Rows) ([]PostDTO, error) {
 	if err != nil {
 		return nil, err
 	}
+	lang := requestLangCode(r)
+	tagsByPost, err := loadPostTagNamesByPostIDs(r.Context(), poolFrom(r), ids, lang)
+	if err != nil {
+		return nil, err
+	}
 	for i := range list {
 		uid, _ := uuid.Parse(list[i].ID)
 		if a, ok := atts[uid]; ok {
 			list[i].Attachments = a
 		}
+		if t, ok := tagsByPost[uid]; ok {
+			list[i].Tags = t
+		} else {
+			list[i].Tags = []string{}
+		}
 	}
 	return list, nil
 }