error handling: use 400 page with error passed instead of flash()

3 files changed, 23 insertions, 21 deletions

diff --git a/python/fatcat_web/editing_routes.py b/python/fatcat_web/editing_routes.py
index e66f29c9..ffce35f3 100644
--- a/python/fatcat_web/editing_routes.py
+++ b/python/fatcat_web/editing_routes.py
@@ -79,8 +79,7 @@ def generic_entity_edit(editgroup_id, entity_type, existing_ident, edit_template
 
         # check that editgroup is edit-able
         if editgroup.changelog_index != None:
-            flash("Editgroup already merged")
-            abort(400)
+            abort(400, "Editgroup already merged")
 
     # fetch entity (if set) or 404
     existing = None
@@ -206,8 +205,7 @@ def generic_edit_delete(editgroup_id, entity_type, edit_id):
 
         # check that editgroup is edit-able
         if editgroup.changelog_index != None:
-            flash("Editgroup already merged")
-            abort(400)
+            abort(400, "Editgroup already merged")
 
     # API on behalf of user
     user_api = auth_api(session['api_token'])
diff --git a/python/fatcat_web/routes.py b/python/fatcat_web/routes.py
index 71946d14..6f3ec21b 100644
--- a/python/fatcat_web/routes.py
+++ b/python/fatcat_web/routes.py
@@ -503,8 +503,7 @@ def editgroup_create_annotation(ident):
     try:
         eg = user_api.get_editgroup(str(ident))
         if eg.changelog_index:
-            flash("Editgroup already accepted")
-            abort(400)
+            abort(400, "Editgroup already accepted")
         ega = EditgroupAnnotation(
             comment_markdown=comment_markdown,
             extra=None,
@@ -525,8 +524,7 @@ def editgroup_accept(ident):
     try:
         eg = user_api.get_editgroup(str(ident))
         if eg.changelog_index:
-            flash("Editgroup already accepted")
-            abort(400)
+            abort(400, "Editgroup already accepted")
         user_api.accept_editgroup(str(ident))
     except ApiException as ae:
         app.log.info(ae)
@@ -543,8 +541,7 @@ def editgroup_unsubmit(ident):
     try:
         eg = user_api.get_editgroup(str(ident))
         if eg.changelog_index:
-            flash("Editgroup already accepted")
-            abort(400)
+            abort(400, "Editgroup already accepted")
         user_api.update_editgroup(eg.editgroup_id, eg, submit=False)
     except ApiException as ae:
         app.log.info(ae)
@@ -561,8 +558,7 @@ def editgroup_submit(ident):
     try:
         eg = user_api.get_editgroup(str(ident))
         if eg.changelog_index:
-            flash("Editgroup already accepted")
-            abort(400)
+            abort(400, "Editgroup already accepted")
         user_api.update_editgroup(eg.editgroup_id, eg, submit=True)
     except ApiException as ae:
         app.log.info(ae)
@@ -762,8 +758,7 @@ def stats_json():
 @crossdomain(origin='*',headers=['access-control-allow-origin','Content-Type'])
 def container_issnl_stats(issnl):
     if not (len(issnl) == 9 and issnl[4] == '-'):
-        flash("Not a valid ISSN-L: {}".format(issnl))
-        abort(400)
+        abort(400, "Not a valid ISSN-L: {}".format(issnl))
     try:
         container = api.lookup_container(issnl=issnl)
     except ApiException as ae:
@@ -917,8 +912,7 @@ def create_auth_token():
             duration_seconds = int(duration_seconds)
             assert duration_seconds >= 1
         except (ValueError, AssertionError):
-            flash("duration_seconds must be a positive non-zero integer")
-            abort(400)
+            abort(400, "duration_seconds must be a positive non-zero integer")
 
     # check user's auth. api_token and editor_id are signed together in session
     # cookie, so if api_token is valid editor_id is assumed to match. If that
@@ -986,7 +980,7 @@ def page_method_not_allowed(e):
 
 @app.errorhandler(400)
 def page_bad_request(e):
-    return render_template('400.html'), 400
+    return render_template('400.html', err=e), 400
 
 @app.errorhandler(409)
 def page_edit_conflict(e):
diff --git a/python/fatcat_web/templates/400.html b/python/fatcat_web/templates/400.html
index f2659ca2..21f98aad 100644
--- a/python/fatcat_web/templates/400.html
+++ b/python/fatcat_web/templates/400.html
@@ -4,10 +4,20 @@
 <center>
 <div style="font-size: 8em;">400</div>
 <div style="font-size: 3em;">Bad Request</div>
-
-<p>Wasn't able to handle the request, either due to incorrect or unexpected
-input. Usually more context should be available; if you hit this page it means
-you've discovered a new corner case!
 </center>
 
+<div class="ui icon error message">
+  <i class="ban icon"></i>
+  <div class="content">
+    <div class="header"></div>
+    {% if err and err.description %}
+      <p>{{ err.description }}
+    {% else %}
+      <p>Wasn't able to handle the request, either due to incorrect or unexpected
+      input. Usually more context should be available; if you hit this page it means
+      you've discovered a new corner case!
+    {% endif %}
+  </div>
+</div>
+
 {% endblock %}