Fix middleware to do exactly what we want/need

ivatar/middleware.py

@@ -6,21 +6,13 @@ from django.utils.deprecation import MiddlewareMixin
 class MultipleProxyMiddleware(MiddlewareMixin):  # pylint: disable=too-few-public-methods
     """
     Middleware to rewrite proxy headers for deployments
-    multiple proxies
+    with multiple proxies
     """
-    FORWARDED_FOR_FIELDS = [
-        'HTTP_X_FORWARDED_FOR',
-        'HTTP_X_FORWARDED_HOST',
-        'HTTP_X_FORWARDED_SERVER',
-    ]
 
     def process_request(self, request):
         """
-        Rewrites the proxy headers so that only the most
-        recent proxy is used.
+        Rewrites the proxy headers so that forwarded server is
+        used if available.
         """
-        for field in self.FORWARDED_FOR_FIELDS:
-            if field in request.META:
-                if ',' in request.META[field]:
-                    parts = request.META[field].split(',')
-                    request.META[field] = parts[-1].strip()
+        if 'HTTP_X_FORWARDED_SERVER' in request.META:
+            request.META['HTTP_X_FORWARDED_HOST'] = request.META['HTTP_X_FORWARDED_SERVER']