Manually generate the default config yaml, remove most of the commandline arguments for synapse anticipating that people will use the yaml instead. Simpify implementing config options by not requiring the classes to hit the super class

synapse/config/metrics.py

@@ -17,20 +17,17 @@ from ._base import Config
 
 
 class MetricsConfig(Config):
-    def __init__(self, args):
-        super(MetricsConfig, self).__init__(args)
-        self.enable_metrics = args.enable_metrics
-        self.metrics_port = args.metrics_port
+    def read_config(self, config):
+        self.enable_metrics = config["enable_metrics"]
+        self.metrics_port = config["metrics_port"]
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(MetricsConfig, cls).add_arguments(parser)
-        metrics_group = parser.add_argument_group("metrics")
-        metrics_group.add_argument(
-            '--enable-metrics', dest="enable_metrics", action="store_true",
-            help="Enable collection and rendering of performance metrics"
-        )
-        metrics_group.add_argument(
-            '--metrics-port', metavar="PORT", type=int,
-            help="Separate port to accept metrics requests on (on localhost)"
-        )
+    def default_config(self, config_dir_path, server_name):
+        return """\
+        ## Metrics ###
+
+        # Enable collection and rendering of performance metrics
+        enable_metrics: False
+
+        # Separate port to accept metrics requests on (on localhost)
+        metrics_port: ~
+        """