400 error messages

catalog/views.py

@@ -1,4 +1,5 @@
 import logging
+from django.contrib import messages
 from django.shortcuts import render, get_object_or_404, redirect
 from django.contrib.auth.decorators import login_required, permission_required
 from django.utils.translation import gettext_lazy as _
@@ -147,7 +148,7 @@ def create(request, item_model):
             form.instance.save()
             return redirect(form.instance.url)
         else:
-            raise BadRequest()
+            raise BadRequest(form.errors)
     else:
         raise BadRequest()
 
@@ -175,7 +176,7 @@ def edit(request, item_path, item_uuid):
             form.instance.save()
             return redirect(form.instance.url)
         else:
-            raise BadRequest()
+            raise BadRequest(form.errors)
     else:
         raise BadRequest()
 
@@ -233,7 +234,7 @@ def merge(request, item_path, item_uuid):
     item = get_object_or_404(Item, uid=get_uuid_or_404(item_uuid))
     new_item = Item.get_by_url(request.POST.get("new_item_url"))
     if not new_item or new_item.is_deleted or new_item.merged_to_item_id:
-        raise BadRequest()
+        raise BadRequest("Can't merge to a deleted or redirected item")
     _logger.warn(f"{request.user} merges {item} to {new_item}")
     item.merge_to(new_item)
     update_journal_for_merged_item(item_uuid)

common/templates/400.html

@@ -29,6 +29,7 @@
           无效的请求
         </div>
         <div class="sec-msg">
+          {{ exception }}
           您可能提交了无效的数据，或者相关内容已被作者删除。如果您确信这是我们的错误，欢迎通过页面底部的链接联系。
         </div>
       </div>

common/views.py

@@ -1,3 +1,4 @@
+from django.contrib import messages
 from django.shortcuts import redirect, render
 from django.urls import reverse
 from django.contrib.auth.decorators import login_required
@@ -18,7 +19,12 @@ def home(request):
 
 
 def error_400(request, exception=None):
-    return render(request, "400.html", status=400)
+    return render(
+        request,
+        "400.html",
+        {"exception": exception},
+        status=400,
+    )
 
 
 def error_403(request, exception=None):