add server header and status code in middleware (#204)

* add server header in middleware

* fix #205

snare/middlewares.py

@@ -4,8 +4,9 @@
 
 class SnareMiddleware():
 
-    def __init__(self, file_name):
+    def __init__(self, file_name, server_header):
         self.error_404 = file_name
+        self.server_header = server_header
 
     async def handle_404(self, request):
         return aiohttp_jinja2.render_template(self.error_404, request, {})
@@ -19,9 +20,13 @@ def create_error_middleware(self, overrides):
         async def error_middleware(request, handler):
             try:
                 response = await handler(request)
-                override = overrides.get(response.status)
+                status = response.status
+                override = overrides.get(status)
                 if override:
-                    return await override(request)
+                    response = await override(request)
+                    response.headers['Server'] = self.server_header
+                    response.set_status(status)
+                    return response
                 return response
             except web.HTTPException as ex:
                 override = overrides.get(ex.status)

snare/server.py

@@ -88,7 +88,10 @@ async def start(self):
         aiohttp_jinja2.setup(
             app, loader=jinja2.FileSystemLoader(self.dir)
         )
-        middleware = SnareMiddleware(self.meta['/status_404']['hash'])
+        middleware = SnareMiddleware(
+            self.meta['/status_404']['hash'],
+            self.run_args.server_header
+        )
         middleware.setup_middlewares(app)
 
         self.runner = web.AppRunner(app)