1 files changed, 11 insertions, 2 deletions
diff --git a/synapse/config/_base.py b/synapse/config/_base.py
index c4d3087fa4..a219a83550 100644
--- a/synapse/config/_base.py
+++ b/synapse/config/_base.py
@@ -214,14 +214,20 @@ class Config(object):
             " Defaults to the directory containing the last config file",
         )
 
+        obj = cls()
+
+        obj.invoke_all("add_arguments", config_parser)
+
         config_args = config_parser.parse_args(argv)
 
         config_files = find_config_files(search_paths=config_args.config_path)
 
-        obj = cls()
         obj.read_config_files(
             config_files, keys_directory=config_args.keys_directory, generate_keys=False
         )
+
+        obj.invoke_all("read_arguments", config_args)
+
         return obj
 
     @classmethod
@@ -399,7 +405,10 @@ class Config(object):
             self.invoke_all("generate_files", config)
             return
 
-        self.invoke_all("read_config", config)
+        self.parse_config_dict(config)
+
+    def parse_config_dict(self, config_dict):
+        self.invoke_all("read_config", config_dict)
 
 
 def find_config_files(search_paths):