Add a --generate-keys option

synapse/config/_base.py

@@ -138,6 +138,11 @@ class Config(object):
             action="store_true",
             help="Generate a config file for the server name"
         )
+        config_parser.add_argument(
+            "--generate-keys",
+            action="store_true",
+            help="Generate any missing key files then exit"
+        )
         config_parser.add_argument(
             "-H", "--server-name",
             help="The server name to generate a config file for"
@@ -230,4 +235,8 @@ class Config(object):
 
         obj.invoke_all("read_arguments", args)
 
+        if config_args.generate_keys:
+            obj.invoke_all("generate_files", config)
+            sys.exit(0)
+
         return obj