Exception handling for database queries

ref-test/app/__init__.py

@@ -1,11 +1,13 @@
 from .config import Production as Config
 from .models import User
 from .extensions import bootstrap, csrf, db, login_manager, mail
+from .tools.logs import write
 
 from flask import flash, Flask, render_template, request
-from flask.helpers import url_for
+from flask.helpers import abort, url_for
 from flask.json import jsonify
 from flask_wtf.csrf import CSRFError
+from sqlalchemy.exc import SQLAlchemyError
 from werkzeug.middleware.proxy_fix import ProxyFix
 
 from datetime import datetime
@@ -24,7 +26,10 @@ def create_app():
     login_manager.login_view = 'admin._login'
     @login_manager.user_loader
     def _load_user(id):
-        return User.query.filter_by(id=id).first()
+        try: return User.query.filter_by(id=id).first()
+        except SQLAlchemyError as exception:
+            write('system.log', f'Database error when loading user fo login manager: {exception}')
+            return abort(500)
 
     @app.before_request
     def _check_cookie_consent():