Add config tree to synapse. Add support for reading config from a file

synapse/config/database.py

@@ -0,0 +1,36 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014 matrix.org
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ._base import Config
+import os
+
+class DatabaseConfig(Config):
+    def __init__(self, args):
+        self.db_path = os.path.abspath(args.database_path)
+
+    @classmethod
+    def add_arguments(cls, parser):
+        super(DatabaseConfig, cls).add_arguments(parser)
+        db_group = parser.add_argument_group("database")
+        db_group.add_argument(
+            "-d", "--database", dest="database_path", default="homeserver.db",
+            help="The database name."
+        )
+
+    @classmethod
+    def generate_config(cls, args, config_dir_path):
+        super(DatabaseConfig, cls).generate_config(args, config_dir_path)
+        args.database_path = os.path.abspath(args.database_path)
+