Use werkzeugs pre implemented ProxyFix middleware

config.py

@@ -1,3 +1,4 @@
+from werkzeug.middleware.proxy_fix import ProxyFix
 import os
 import logging
 
@@ -33,7 +34,13 @@ class Config:
 
     @staticmethod
     def init_app(app):
-        pass
+        proxy_fix_kwargs = {
+            'x_for': 1,
+            'x_host': 1,
+            'x_port': 1,
+            'x_proto': 1,
+        }
+        app.wsgi_app = ProxyFix(app.wsgi_app, **proxy_fix_kwargs)
 
 
 class DevelopmentConfig(Config):