refac: article title rules are the same in the API request and the domain; an invalid title returns 400 instead of 500

api/handlers/article/articleHandler.go

@@ -23,7 +23,7 @@ type Handler struct {
 }
 
 type PostArticle struct {
-	Title string `json:"title" validate:"required,min=3,max=50"`
+	Title string `json:"title" validate:"required,min=3,max=200"`
 	Body  string `json:"body" validate:"required,max=10000"`
 }
 
@@ -81,6 +81,10 @@ func (h *Handler) PostArticle(w http.ResponseWriter, r *http.Request) {
 		Body:  localArticle.Body,
 	})
 	if err != nil {
+		if errors.Is(err, domain.ErrInvalidTitle) {
+			http.Error(w, apperr.ArticleTitleErrorMessage, http.StatusBadRequest)
+			return
+		}
 		http.Error(w, "Failed to create article", http.StatusInternalServerError)
 		return
 	}