Add new config "enable_login".

etiquette/constants.py

@@ -156,6 +156,7 @@ DEFAULT_CONFIGURATION = {
     'cache_size_user': 200,
 
     'enable_album_edit': True,
+    'enable_login': True,
     'enable_new_album': True,
     'enable_new_bookmark': True,
     'enable_new_photo': True,

etiquette/photodb.py

@@ -1006,6 +1006,7 @@ class PDBUserMixin:
             author_id = None
         return author_id
 
+    @decorators.required_feature('enable_login')
     def login(self, user_id, password):
         cur = self.sql.cursor()
         cur.execute('SELECT * FROM users WHERE id == ?', [user_id])

frontends/etiquette_flask/etiquette_flask/etiquette_flask.py

@@ -648,6 +648,9 @@ def post_login():
         e = etiquette.exceptions.WrongLogin()
         response = etiquette.jsonify.exception(e)
         return jsonify.make_json_response(response, status=422)
+    except etiquette.exceptions.FeatureDisabled as e:
+        response = etiquette.jsonify.exception(e)
+        return jsonify.make_json_response(response, status=400)
     session = sessions.Session(request, user)
     session_manager.add(session)
     return jsonify.make_json_response({})