Merge pull request #136 from matrix-org/markjh/config_cleanup

Config restructuring.

14 files changed, 552 insertions, 474 deletions

diff --git a/synapse/config/_base.py b/synapse/config/_base.py
index b59f4e45e2..cd4bd28e8c 100644
--- a/synapse/config/_base.py
+++ b/synapse/config/_base.py
@@ -14,9 +14,10 @@
 # limitations under the License.
 
 import argparse
-import sys
 import os
 import yaml
+import sys
+from textwrap import dedent
 
 
 class ConfigError(Exception):
@@ -24,18 +25,35 @@ class ConfigError(Exception):
 
 
 class Config(object):
-    def __init__(self, args):
-        pass
 
     @staticmethod
-    def parse_size(string):
+    def parse_size(value):
+        if isinstance(value, int) or isinstance(value, long):
+            return value
         sizes = {"K": 1024, "M": 1024 * 1024}
         size = 1
-        suffix = string[-1]
+        suffix = value[-1]
         if suffix in sizes:
-            string = string[:-1]
+            value = value[:-1]
             size = sizes[suffix]
-        return int(string) * size
+        return int(value) * size
+
+    @staticmethod
+    def parse_duration(value):
+        if isinstance(value, int) or isinstance(value, long):
+            return value
+        second = 1000
+        hour = 60 * 60 * second
+        day = 24 * hour
+        week = 7 * day
+        year = 365 * day
+        sizes = {"s": second, "h": hour, "d": day, "w": week, "y": year}
+        size = 1
+        suffix = value[-1]
+        if suffix in sizes:
+            value = value[:-1]
+            size = sizes[suffix]
+        return int(value) * size
 
     @staticmethod
     def abspath(file_path):
@@ -77,17 +95,6 @@ class Config(object):
         with open(file_path) as file_stream:
             return file_stream.read()
 
-    @classmethod
-    def read_yaml_file(cls, file_path, config_name):
-        cls.check_file(file_path, config_name)
-        with open(file_path) as file_stream:
-            try:
-                return yaml.load(file_stream)
-            except:
-                raise ConfigError(
-                    "Error parsing yaml in file %r" % (file_path,)
-                )
-
     @staticmethod
     def default_path(name):
         return os.path.abspath(os.path.join(os.path.curdir, name))
@@ -97,84 +104,119 @@ class Config(object):
         with open(file_path) as file_stream:
             return yaml.load(file_stream)
 
-    @classmethod
-    def add_arguments(cls, parser):
-        pass
+    def invoke_all(self, name, *args, **kargs):
+        results = []
+        for cls in type(self).mro():
+            if name in cls.__dict__:
+                results.append(getattr(cls, name)(self, *args, **kargs))
+        return results
 
-    @classmethod
-    def generate_config(cls, args, config_dir_path):
-        pass
+    def generate_config(self, config_dir_path, server_name):
+        default_config = "# vim:ft=yaml\n"
+
+        default_config += "\n\n".join(dedent(conf) for conf in self.invoke_all(
+            "default_config", config_dir_path, server_name
+        ))
+
+        config = yaml.load(default_config)
+
+        return default_config, config
 
     @classmethod
     def load_config(cls, description, argv, generate_section=None):
+        obj = cls()
+
         config_parser = argparse.ArgumentParser(add_help=False)
         config_parser.add_argument(
             "-c", "--config-path",
+            action="append",
             metavar="CONFIG_FILE",
             help="Specify config file"
         )
         config_parser.add_argument(
             "--generate-config",
             action="store_true",
-            help="Generate config file"
+            help="Generate a config file for the server name"
+        )
+        config_parser.add_argument(
+            "-H", "--server-name",
+            help="The server name to generate a config file for"
         )
         config_args, remaining_args = config_parser.parse_known_args(argv)
 
+        if not config_args.config_path:
+            config_parser.error(
+                "Must supply a config file.\nA config file can be automatically"
+                " generated using \"--generate-config -h SERVER_NAME"
+                " -c CONFIG-FILE\""
+            )
+
+        config_dir_path = os.path.dirname(config_args.config_path[0])
+        config_dir_path = os.path.abspath(config_dir_path)
         if config_args.generate_config:
-            if not config_args.config_path:
-                config_parser.error(
-                    "Must specify where to generate the config file"
+            server_name = config_args.server_name
+            if not server_name:
+                print "Most specify a server_name to a generate config for."
+                sys.exit(1)
+            (config_path,) = config_args.config_path
+            if not os.path.exists(config_dir_path):
+                os.makedirs(config_dir_path)
+            if os.path.exists(config_path):
+                print "Config file %r already exists" % (config_path,)
+                yaml_config = cls.read_config_file(config_path)
+                yaml_name = yaml_config["server_name"]
+                if server_name != yaml_name:
+                    print (
+                        "Config file %r has a different server_name: "
+                        " %r != %r" % (config_path, server_name, yaml_name)
+                    )
+                    sys.exit(1)
+                config_bytes, config = obj.generate_config(
+                    config_dir_path, server_name
+                )
+                config.update(yaml_config)
+                print "Generating any missing keys for %r" % (server_name,)
+                obj.invoke_all("generate_files", config)
+                sys.exit(0)
+            with open(config_path, "wb") as config_file:
+                config_bytes, config = obj.generate_config(
+                    config_dir_path, server_name
                 )
-            config_dir_path = os.path.dirname(config_args.config_path)
-            if os.path.exists(config_args.config_path):
-                defaults = cls.read_config_file(config_args.config_path)
-            else:
-                defaults = {}
-        else:
-            if config_args.config_path:
-                defaults = cls.read_config_file(config_args.config_path)
-            else:
-                defaults = {}
+                obj.invoke_all("generate_files", config)
+                config_file.write(config_bytes)
+                print (
+                    "A config file has been generated in %s for server name"
+                    " '%s' with corresponding SSL keys and self-signed"
+                    " certificates. Please review this file and customise it to"
+                    " your needs."
+                ) % (config_path, server_name)
+            print (
+                "If this server name is incorrect, you will need to regenerate"
+                " the SSL certificates"
+            )
+            sys.exit(0)
+
+        specified_config = {}
+        for config_path in config_args.config_path:
+            yaml_config = cls.read_config_file(config_path)
+            specified_config.update(yaml_config)
+
+        server_name = specified_config["server_name"]
+        _, config = obj.generate_config(config_dir_path, server_name)
+        config.pop("log_config")
+        config.update(specified_config)
+
+        obj.invoke_all("read_config", config)
 
         parser = argparse.ArgumentParser(
             parents=[config_parser],
             description=description,
             formatter_class=argparse.RawDescriptionHelpFormatter,
         )
-        cls.add_arguments(parser)
-        parser.set_defaults(**defaults)
 
+        obj.invoke_all("add_arguments", parser)
         args = parser.parse_args(remaining_args)
 
-        if config_args.generate_config:
-            config_dir_path = os.path.dirname(config_args.config_path)
-            config_dir_path = os.path.abspath(config_dir_path)
-            if not os.path.exists(config_dir_path):
-                os.makedirs(config_dir_path)
-            cls.generate_config(args, config_dir_path)
-            config = {}
-            for key, value in vars(args).items():
-                if (key not in set(["config_path", "generate_config"])
-                        and value is not None):
-                    config[key] = value
-            with open(config_args.config_path, "w") as config_file:
-                # TODO(mark/paul) We might want to output emacs-style mode
-                # markers as well as vim-style mode markers into the file,
-                # to further hint to people this is a YAML file.
-                config_file.write("# vim:ft=yaml\n")
-                yaml.dump(config, config_file, default_flow_style=False)
-            print (
-                "A config file has been generated in %s for server name"
-                " '%s' with corresponding SSL keys and self-signed"
-                " certificates. Please review this file and customise it to"
-                " your needs."
-            ) % (
-                config_args.config_path, config['server_name']
-            )
-            print (
-                "If this server name is incorrect, you will need to regenerate"
-                " the SSL certificates"
-            )
-            sys.exit(0)
+        obj.invoke_all("read_arguments", args)
 
-        return cls(args)
+        return obj
diff --git a/synapse/config/appservice.py b/synapse/config/appservice.py
index 399a716d80..38f41933b7 100644
--- a/synapse/config/appservice.py
+++ b/synapse/config/appservice.py
@@ -17,15 +17,11 @@ from ._base import Config
 
 class AppServiceConfig(Config):
 
-    def __init__(self, args):
-        super(AppServiceConfig, self).__init__(args)
-        self.app_service_config_files = args.app_service_config_files
+    def read_config(self, config):
+        self.app_service_config_files = config.get("app_service_config_files", [])
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(AppServiceConfig, cls).add_arguments(parser)
-        group = parser.add_argument_group("appservice")
-        group.add_argument(
-            "--app-service-config-files", type=str, nargs='+',
-            help="A list of application service config files to use."
-        )
+    def default_config(cls, config_dir_path, server_name):
+        return """\
+        # A list of application service config file to use
+        app_service_config_files: []
+        """
diff --git a/synapse/config/captcha.py b/synapse/config/captcha.py
index 456ce9c632..d8fe577e34 100644
--- a/synapse/config/captcha.py
+++ b/synapse/config/captcha.py
@@ -17,42 +17,35 @@ from ._base import Config
 
 class CaptchaConfig(Config):
 
-    def __init__(self, args):
-        super(CaptchaConfig, self).__init__(args)
-        self.recaptcha_private_key = args.recaptcha_private_key
-        self.recaptcha_public_key = args.recaptcha_public_key
-        self.enable_registration_captcha = args.enable_registration_captcha
-
+    def read_config(self, config):
+        self.recaptcha_private_key = config["recaptcha_private_key"]
+        self.recaptcha_public_key = config["recaptcha_public_key"]
+        self.enable_registration_captcha = config["enable_registration_captcha"]
         # XXX: This is used for more than just captcha
         self.captcha_ip_origin_is_x_forwarded = (
-            args.captcha_ip_origin_is_x_forwarded
-        )
-        self.captcha_bypass_secret = args.captcha_bypass_secret
-
-    @classmethod
-    def add_arguments(cls, parser):
-        super(CaptchaConfig, cls).add_arguments(parser)
-        group = parser.add_argument_group("recaptcha")
-        group.add_argument(
-            "--recaptcha-public-key", type=str, default="YOUR_PUBLIC_KEY",
-            help="This Home Server's ReCAPTCHA public key."
-        )
-        group.add_argument(
-            "--recaptcha-private-key", type=str, default="YOUR_PRIVATE_KEY",
-            help="This Home Server's ReCAPTCHA private key."
-        )
-        group.add_argument(
-            "--enable-registration-captcha", type=bool, default=False,
-            help="Enables ReCaptcha checks when registering, preventing signup"
-            + " unless a captcha is answered. Requires a valid ReCaptcha "
-            + "public/private key."
-        )
-        group.add_argument(
-            "--captcha_ip_origin_is_x_forwarded", type=bool, default=False,
-            help="When checking captchas, use the X-Forwarded-For (XFF) header"
-            + " as the client IP and not the actual client IP."
-        )
-        group.add_argument(
-            "--captcha_bypass_secret", type=str,
-            help="A secret key used to bypass the captcha test entirely."
+            config["captcha_ip_origin_is_x_forwarded"]
         )
+        self.captcha_bypass_secret = config.get("captcha_bypass_secret")
+
+    def default_config(self, config_dir_path, server_name):
+        return """\
+        ## Captcha ##
+
+        # This Home Server's ReCAPTCHA public key.
+        recaptcha_private_key: "YOUR_PUBLIC_KEY"
+
+        # This Home Server's ReCAPTCHA private key.
+        recaptcha_public_key: "YOUR_PRIVATE_KEY"
+
+        # Enables ReCaptcha checks when registering, preventing signup
+        # unless a captcha is answered. Requires a valid ReCaptcha
+        # public/private key.
+        enable_registration_captcha: False
+
+        # When checking captchas, use the X-Forwarded-For (XFF) header
+        # as the client IP and not the actual client IP.
+        captcha_ip_origin_is_x_forwarded: False
+
+        # A secret key used to bypass the captcha test entirely.
+        #captcha_bypass_secret: "YOUR_SECRET_HERE"
+        """
diff --git a/synapse/config/database.py b/synapse/config/database.py
index 190d119df4..f0611e8884 100644
--- a/synapse/config/database.py
+++ b/synapse/config/database.py
@@ -14,28 +14,21 @@
 # limitations under the License.
 
 from ._base import Config
-import os
-import yaml
 
 
 class DatabaseConfig(Config):
-    def __init__(self, args):
-        super(DatabaseConfig, self).__init__(args)
-        if args.database_path == ":memory:":
-            self.database_path = ":memory:"
-        else:
-            self.database_path = self.abspath(args.database_path)
-        self.event_cache_size = self.parse_size(args.event_cache_size)
 
-        if args.database_config:
-            with open(args.database_config) as f:
-                self.database_config = yaml.safe_load(f)
-        else:
+    def read_config(self, config):
+        self.event_cache_size = self.parse_size(
+            config.get("event_cache_size", "10K")
+        )
+
+        self.database_config = config.get("database")
+
+        if self.database_config is None:
             self.database_config = {
                 "name": "sqlite3",
-                "args": {
-                    "database": self.database_path,
-                },
+                "args": {},
             }
 
         name = self.database_config.get("name", None)
@@ -50,24 +43,37 @@ class DatabaseConfig(Config):
         else:
             raise RuntimeError("Unsupported database type '%s'" % (name,))
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(DatabaseConfig, cls).add_arguments(parser)
+        self.set_databasepath(config.get("database_path"))
+
+    def default_config(self, config, config_dir_path):
+        database_path = self.abspath("homeserver.db")
+        return """\
+        # Database configuration
+        database:
+          # The database engine name
+          name: "sqlite3"
+          # Arguments to pass to the engine
+          args:
+            # Path to the database
+            database: "%(database_path)s"
+
+        # Number of events to cache in memory.
+        event_cache_size: "10K"
+        """ % locals()
+
+    def read_arguments(self, args):
+        self.set_databasepath(args.database_path)
+
+    def set_databasepath(self, database_path):
+        if database_path != ":memory:":
+            database_path = self.abspath(database_path)
+        if self.database_config.get("name", None) == "sqlite3":
+            if database_path is not None:
+                self.database_config["args"]["database"] = database_path
+
+    def add_arguments(self, parser):
         db_group = parser.add_argument_group("database")
         db_group.add_argument(
-            "-d", "--database-path", default="homeserver.db",
-            metavar="SQLITE_DATABASE_PATH", help="The database name."
-        )
-        db_group.add_argument(
-            "--event-cache-size", default="100K",
-            help="Number of events to cache in memory."
+            "-d", "--database-path", metavar="SQLITE_DATABASE_PATH",
+            help="The path to a sqlite database to use."
         )
-        db_group.add_argument(
-            "--database-config", default=None,
-            help="Location of the database configuration file."
-        )
-
-    @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)
diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index 1c8ff38465..fe0ccb6eb7 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -36,4 +36,6 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
 
 if __name__ == '__main__':
     import sys
-    HomeServerConfig.load_config("Generate config", sys.argv[1:], "HomeServer")
+    sys.stdout.write(
+        HomeServerConfig().generate_config(sys.argv[1], sys.argv[2])[0]
+    )
diff --git a/synapse/config/key.py b/synapse/config/key.py
index a2de6d5c17..0494c0cb77 100644
--- a/synapse/config/key.py
+++ b/synapse/config/key.py
@@ -20,48 +20,58 @@ from syutil.crypto.signing_key import (
     is_signing_algorithm_supported, decode_verify_key_bytes
 )
 from syutil.base64util import decode_base64
+from synapse.util.stringutils import random_string
 
 
 class KeyConfig(Config):
 
-    def __init__(self, args):
-        super(KeyConfig, self).__init__(args)
-        self.signing_key = self.read_signing_key(args.signing_key_path)
+    def read_config(self, config):
+        self.signing_key = self.read_signing_key(config["signing_key_path"])
         self.old_signing_keys = self.read_old_signing_keys(
-            args.old_signing_key_path
+            config["old_signing_keys"]
+        )
+        self.key_refresh_interval = self.parse_duration(
+            config["key_refresh_interval"]
         )
-        self.key_refresh_interval = args.key_refresh_interval
         self.perspectives = self.read_perspectives(
-            args.perspectives_config_path
+            config["perspectives"]
         )
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(KeyConfig, cls).add_arguments(parser)
-        key_group = parser.add_argument_group("keys")
-        key_group.add_argument("--signing-key-path",
-                               help="The signing key to sign messages with")
-        key_group.add_argument("--old-signing-key-path",
-                               help="The keys that the server used to sign"
-                                    " sign messages with but won't use"
-                                    " to sign new messages. E.g. it has"
-                                    " lost its private key")
-        key_group.add_argument("--key-refresh-interval",
-                               default=24 * 60 * 60 * 1000,  # 1 Day
-                               help="How long a key response is valid for."
-                                    " Used to set the exipiry in /key/v2/."
-                                    " Controls how frequently servers will"
-                                    " query what keys are still valid")
-        key_group.add_argument("--perspectives-config-path",
-                               help="The trusted servers to download signing"
-                                    " keys from")
-
-    def read_perspectives(self, perspectives_config_path):
-        config = self.read_yaml_file(
-            perspectives_config_path, "perspectives_config_path"
-        )
+    def default_config(self, config_dir_path, server_name):
+        base_key_name = os.path.join(config_dir_path, server_name)
+        return """\
+        ## Signing Keys ##
+
+        # Path to the signing key to sign messages with
+        signing_key_path: "%(base_key_name)s.signing.key"
+
+        # The keys that the server used to sign messages with but won't use
+        # to sign new messages. E.g. it has lost its private key
+        old_signing_keys: {}
+        #  "ed25519:auto":
+        #    # Base64 encoded public key
+        #    key: "The public part of your old signing key."
+        #    # Millisecond POSIX timestamp when the key expired.
+        #    expired_ts: 123456789123
+
+        # How long key response published by this server is valid for.
+        # Used to set the valid_until_ts in /key/v2 APIs.
+        # Determines how quickly servers will query to check which keys
+        # are still valid.
+        key_refresh_interval: "1d" # 1 Day.
+
+        # The trusted servers to download signing keys from.
+        perspectives:
+          servers:
+            "matrix.org":
+              verify_keys:
+                "ed25519:auto":
+                  key: "Noi6WqcDj0QmPxCNQqgezwTlBKrfqehY1u2FyWP9uYw"
+        """ % locals()
+
+    def read_perspectives(self, perspectives_config):
         servers = {}
-        for server_name, server_config in config["servers"].items():
+        for server_name, server_config in perspectives_config["servers"].items():
             for key_id, key_data in server_config["verify_keys"].items():
                 if is_signing_algorithm_supported(key_id):
                     key_base64 = key_data["key"]
@@ -82,66 +92,42 @@ class KeyConfig(Config):
                 " Try running again with --generate-config"
             )
 
-    def read_old_signing_keys(self, old_signing_key_path):
-        old_signing_keys = self.read_file(
-            old_signing_key_path, "old_signing_key"
-        )
-        try:
-            return syutil.crypto.signing_key.read_old_signing_keys(
-                old_signing_keys.splitlines(True)
-            )
-        except Exception:
-            raise ConfigError(
-                "Error reading old signing keys."
-            )
-
-    @classmethod
-    def generate_config(cls, args, config_dir_path):
-        super(KeyConfig, cls).generate_config(args, config_dir_path)
-        base_key_name = os.path.join(config_dir_path, args.server_name)
-
-        args.pid_file = os.path.abspath(args.pid_file)
-
-        if not args.signing_key_path:
-            args.signing_key_path = base_key_name + ".signing.key"
+    def read_old_signing_keys(self, old_signing_keys):
+        keys = {}
+        for key_id, key_data in old_signing_keys.items():
+            if is_signing_algorithm_supported(key_id):
+                key_base64 = key_data["key"]
+                key_bytes = decode_base64(key_base64)
+                verify_key = decode_verify_key_bytes(key_id, key_bytes)
+                verify_key.expired_ts = key_data["expired_ts"]
+                keys[key_id] = verify_key
+            else:
+                raise ConfigError(
+                    "Unsupported signing algorithm for old key: %r" % (key_id,)
+                )
+        return keys
 
-        if not os.path.exists(args.signing_key_path):
-            with open(args.signing_key_path, "w") as signing_key_file:
+    def generate_files(self, config):
+        signing_key_path = config["signing_key_path"]
+        if not os.path.exists(signing_key_path):
+            with open(signing_key_path, "w") as signing_key_file:
+                key_id = "a_" + random_string(4)
                 syutil.crypto.signing_key.write_signing_keys(
                     signing_key_file,
-                    (syutil.crypto.signing_key.generate_signing_key("auto"),),
+                    (syutil.crypto.signing_key.generate_signing_key(key_id),),
                 )
         else:
-            signing_keys = cls.read_file(args.signing_key_path, "signing_key")
+            signing_keys = self.read_file(signing_key_path, "signing_key")
             if len(signing_keys.split("\n")[0].split()) == 1:
                 # handle keys in the old format.
+                key_id = "a_" + random_string(4)
                 key = syutil.crypto.signing_key.decode_signing_key_base64(
                     syutil.crypto.signing_key.NACL_ED25519,
-                    "auto",
+                    key_id,
                     signing_keys.split("\n")[0]
                 )
-                with open(args.signing_key_path, "w") as signing_key_file:
+                with open(signing_key_path, "w") as signing_key_file:
                     syutil.crypto.signing_key.write_signing_keys(
                         signing_key_file,
                         (key,),
                     )
-
-        if not args.old_signing_key_path:
-            args.old_signing_key_path = base_key_name + ".old.signing.keys"
-
-        if not os.path.exists(args.old_signing_key_path):
-            with open(args.old_signing_key_path, "w"):
-                pass
-
-        if not args.perspectives_config_path:
-            args.perspectives_config_path = base_key_name + ".perspectives"
-
-        if not os.path.exists(args.perspectives_config_path):
-            with open(args.perspectives_config_path, "w") as perspectives_file:
-                perspectives_file.write(
-                    'servers:\n'
-                    '  matrix.org:\n'
-                    '    verify_keys:\n'
-                    '      "ed25519:auto":\n'
-                    '         key: "Noi6WqcDj0QmPxCNQqgezwTlBKrfqehY1u2FyWP9uYw"\n'
-                )
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 247b324816..fa542623b7 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -19,25 +19,88 @@ from twisted.python.log import PythonLoggingObserver
 import logging
 import logging.config
 import yaml
+from string import Template
+import os
+
+
+DEFAULT_LOG_CONFIG = Template("""
+version: 1
+
+formatters:
+  precise:
+   format: '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s\
+- %(message)s'
+
+filters:
+  context:
+    (): synapse.util.logcontext.LoggingContextFilter
+    request: ""
+
+handlers:
+  file:
+    class: logging.handlers.RotatingFileHandler
+    formatter: precise
+    filename: ${log_file}
+    maxBytes: 104857600
+    backupCount: 10
+    filters: [context]
+    level: INFO
+  console:
+    class: logging.StreamHandler
+    formatter: precise
+
+loggers:
+    synapse:
+        level: INFO
+
+    synapse.storage.SQL:
+        level: INFO
+
+root:
+    level: INFO
+    handlers: [file, console]
+""")
 
 
 class LoggingConfig(Config):
-    def __init__(self, args):
-        super(LoggingConfig, self).__init__(args)
-        self.verbosity = int(args.verbose) if args.verbose else None
-        self.log_config = self.abspath(args.log_config)
-        self.log_file = self.abspath(args.log_file)
 
-    @classmethod
+    def read_config(self, config):
+        self.verbosity = config.get("verbose", 0)
+        self.log_config = self.abspath(config.get("log_config"))
+        self.log_file = self.abspath(config.get("log_file"))
+
+    def default_config(self, config_dir_path, server_name):
+        log_file = self.abspath("homeserver.log")
+        log_config = self.abspath(
+            os.path.join(config_dir_path, server_name + ".log.config")
+        )
+        return """
+        # Logging verbosity level.
+        verbose: 0
+
+        # File to write logging to
+        log_file: "%(log_file)s"
+
+        # A yaml python logging config file
+        log_config: "%(log_config)s"
+        """ % locals()
+
+    def read_arguments(self, args):
+        if args.verbose is not None:
+            self.verbosity = args.verbose
+        if args.log_config is not None:
+            self.log_config = args.log_config
+        if args.log_file is not None:
+            self.log_file = args.log_file
+
     def add_arguments(cls, parser):
-        super(LoggingConfig, cls).add_arguments(parser)
         logging_group = parser.add_argument_group("logging")
         logging_group.add_argument(
             '-v', '--verbose', dest="verbose", action='count',
             help="The verbosity level."
         )
         logging_group.add_argument(
-            '-f', '--log-file', dest="log_file", default="homeserver.log",
+            '-f', '--log-file', dest="log_file",
             help="File to log to."
         )
         logging_group.add_argument(
@@ -45,6 +108,14 @@ class LoggingConfig(Config):
             help="Python logging config file"
         )
 
+    def generate_files(self, config):
+        log_config = config.get("log_config")
+        if log_config and not os.path.exists(log_config):
+            with open(log_config, "wb") as log_config_file:
+                log_config_file.write(
+                    DEFAULT_LOG_CONFIG.substitute(log_file=config["log_file"])
+                )
+
     def setup_logging(self):
         log_format = (
             "%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s"
diff --git a/synapse/config/metrics.py b/synapse/config/metrics.py
index 901a429c76..71a1b1d189 100644
--- a/synapse/config/metrics.py
+++ b/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.get("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: 8081
+        """
diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 862c07ef8c..76d9970e5b 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -17,56 +17,42 @@ from ._base import Config
 
 class RatelimitConfig(Config):
 
-    def __init__(self, args):
-        super(RatelimitConfig, self).__init__(args)
-        self.rc_messages_per_second = args.rc_messages_per_second
-        self.rc_message_burst_count = args.rc_message_burst_count
+    def read_config(self, config):
+        self.rc_messages_per_second = config["rc_messages_per_second"]
+        self.rc_message_burst_count = config["rc_message_burst_count"]
 
-        self.federation_rc_window_size = args.federation_rc_window_size
-        self.federation_rc_sleep_limit = args.federation_rc_sleep_limit
-        self.federation_rc_sleep_delay = args.federation_rc_sleep_delay
-        self.federation_rc_reject_limit = args.federation_rc_reject_limit
-        self.federation_rc_concurrent = args.federation_rc_concurrent
+        self.federation_rc_window_size = config["federation_rc_window_size"]
+        self.federation_rc_sleep_limit = config["federation_rc_sleep_limit"]
+        self.federation_rc_sleep_delay = config["federation_rc_sleep_delay"]
+        self.federation_rc_reject_limit = config["federation_rc_reject_limit"]
+        self.federation_rc_concurrent = config["federation_rc_concurrent"]
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(RatelimitConfig, cls).add_arguments(parser)
-        rc_group = parser.add_argument_group("ratelimiting")
-        rc_group.add_argument(
-            "--rc-messages-per-second", type=float, default=0.2,
-            help="number of messages a client can send per second"
-        )
-        rc_group.add_argument(
-            "--rc-message-burst-count", type=float, default=10,
-            help="number of message a client can send before being throttled"
-        )
+    def default_config(self, config_dir_path, server_name):
+        return """\
+        ## Ratelimiting ##
 
-        rc_group.add_argument(
-            "--federation-rc-window-size", type=int, default=10000,
-            help="The federation window size in milliseconds",
-        )
+        # Number of messages a client can send per second
+        rc_messages_per_second: 0.2
 
-        rc_group.add_argument(
-            "--federation-rc-sleep-limit", type=int, default=10,
-            help="The number of federation requests from a single server"
-                 " in a window before the server will delay processing the"
-                 " request.",
-        )
+        # Number of message a client can send before being throttled
+        rc_message_burst_count: 10.0
 
-        rc_group.add_argument(
-            "--federation-rc-sleep-delay", type=int, default=500,
-            help="The duration in milliseconds to delay processing events from"
-                 " remote servers by if they go over the sleep limit.",
-        )
+        # The federation window size in milliseconds
+        federation_rc_window_size: 1000
 
-        rc_group.add_argument(
-            "--federation-rc-reject-limit", type=int, default=50,
-            help="The maximum number of concurrent federation requests allowed"
-                 " from a single server",
-        )
+        # The number of federation requests from a single server in a window
+        # before the server will delay processing the request.
+        federation_rc_sleep_limit: 10
 
-        rc_group.add_argument(
-            "--federation-rc-concurrent", type=int, default=3,
-            help="The number of federation requests to concurrently process"
-                 " from a single server",
-        )
+        # The duration in milliseconds to delay processing events from
+        # remote servers by if they go over the sleep limit.
+        federation_rc_sleep_delay: 500
+
+        # The maximum number of concurrent federation requests allowed
+        # from a single server
+        federation_rc_reject_limit: 50
+
+        # The number of federation requests to concurrently process from a
+        # single server
+        federation_rc_concurrent: 3
+        """
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index f412a72f59..b39989a87f 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -17,45 +17,44 @@ from ._base import Config
 
 from synapse.util.stringutils import random_string_with_symbols
 
-import distutils.util
+from distutils.util import strtobool
 
 
 class RegistrationConfig(Config):
 
-    def __init__(self, args):
-        super(RegistrationConfig, self).__init__(args)
-
-        # `args.enable_registration` may either be a bool or a string depending
-        # on if the option was given a value (e.g. --enable-registration=true
-        # would set `args.enable_registration` to "true" not True.)
+    def read_config(self, config):
         self.disable_registration = not bool(
-            distutils.util.strtobool(str(args.enable_registration))
+            strtobool(str(config["enable_registration"]))
         )
-        self.registration_shared_secret = args.registration_shared_secret
+        if "disable_registration" in config:
+            self.disable_registration = bool(
+                strtobool(str(config["disable_registration"]))
+            )
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(RegistrationConfig, cls).add_arguments(parser)
-        reg_group = parser.add_argument_group("registration")
+        self.registration_shared_secret = config.get("registration_shared_secret")
 
+    def default_config(self, config_dir, server_name):
+        registration_shared_secret = random_string_with_symbols(50)
+        return """\
+        ## Registration ##
+
+        # Enable registration for new users.
+        enable_registration: True
+
+        # If set, allows registration by anyone who also has the shared
+        # secret, even if registration is otherwise disabled.
+        registration_shared_secret: "%(registration_shared_secret)s"
+        """ % locals()
+
+    def add_arguments(self, parser):
+        reg_group = parser.add_argument_group("registration")
         reg_group.add_argument(
-            "--enable-registration",
-            const=True,
-            default=False,
-            nargs='?',
-            help="Enable registration for new users.",
-        )
-        reg_group.add_argument(
-            "--registration-shared-secret", type=str,
-            help="If set, allows registration by anyone who also has the shared"
-                 " secret, even if registration is otherwise disabled.",
+            "--enable-registration", action="store_true", default=None,
+            help="Enable registration for new users."
         )
 
-    @classmethod
-    def generate_config(cls, args, config_dir_path):
-        super(RegistrationConfig, cls).generate_config(args, config_dir_path)
-        if args.enable_registration is None:
-            args.enable_registration = False
-
-        if args.registration_shared_secret is None:
-            args.registration_shared_secret = random_string_with_symbols(50)
+    def read_arguments(self, args):
+        if args.enable_registration is not None:
+            self.disable_registration = not bool(
+                strtobool(str(args.enable_registration))
+            )
diff --git a/synapse/config/repository.py b/synapse/config/repository.py
index e1827f05e4..adaf4e4bb2 100644
--- a/synapse/config/repository.py
+++ b/synapse/config/repository.py
@@ -17,32 +17,20 @@ from ._base import Config
 
 
 class ContentRepositoryConfig(Config):
-    def __init__(self, args):
-        super(ContentRepositoryConfig, self).__init__(args)
-        self.max_upload_size = self.parse_size(args.max_upload_size)
-        self.max_image_pixels = self.parse_size(args.max_image_pixels)
-        self.media_store_path = self.ensure_directory(args.media_store_path)
+    def read_config(self, config):
+        self.max_upload_size = self.parse_size(config["max_upload_size"])
+        self.max_image_pixels = self.parse_size(config["max_image_pixels"])
+        self.media_store_path = self.ensure_directory(config["media_store_path"])
 
-    def parse_size(self, string):
-        sizes = {"K": 1024, "M": 1024 * 1024}
-        size = 1
-        suffix = string[-1]
-        if suffix in sizes:
-            string = string[:-1]
-            size = sizes[suffix]
-        return int(string) * size
+    def default_config(self, config_dir_path, server_name):
+        media_store = self.default_path("media_store")
+        return """
+        # Directory where uploaded images and attachments are stored.
+        media_store_path: "%(media_store)s"
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(ContentRepositoryConfig, cls).add_arguments(parser)
-        db_group = parser.add_argument_group("content_repository")
-        db_group.add_argument(
-            "--max-upload-size", default="10M"
-        )
-        db_group.add_argument(
-            "--media-store-path", default=cls.default_path("media_store")
-        )
-        db_group.add_argument(
-            "--max-image-pixels", default="32M",
-            help="Maximum number of pixels that will be thumbnailed"
-        )
+        # The largest allowed upload size in bytes
+        max_upload_size: "10M"
+
+        # Maximum number of pixels that will be thumbnailed
+        max_image_pixels: "32M"
+        """ % locals()
diff --git a/synapse/config/server.py b/synapse/config/server.py
index c25feb4c58..f20d3fd389 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -17,64 +17,85 @@ from ._base import Config
 
 
 class ServerConfig(Config):
-    def __init__(self, args):
-        super(ServerConfig, self).__init__(args)
-        self.server_name = args.server_name
-        self.bind_port = args.bind_port
-        self.bind_host = args.bind_host
-        self.unsecure_port = args.unsecure_port
-        self.daemonize = args.daemonize
-        self.pid_file = self.abspath(args.pid_file)
-        self.web_client = args.web_client
-        self.manhole = args.manhole
-        self.soft_file_limit = args.soft_file_limit
 
-        if not args.content_addr:
-            host = args.server_name
+    def read_config(self, config):
+        self.server_name = config["server_name"]
+        self.bind_port = config["bind_port"]
+        self.bind_host = config["bind_host"]
+        self.unsecure_port = config["unsecure_port"]
+        self.manhole = config.get("manhole")
+        self.pid_file = self.abspath(config.get("pid_file"))
+        self.web_client = config["web_client"]
+        self.soft_file_limit = config["soft_file_limit"]
+
+        # Attempt to guess the content_addr for the v0 content repostitory
+        content_addr = config.get("content_addr")
+        if not content_addr:
+            host = self.server_name
             if ':' not in host:
-                host = "%s:%d" % (host, args.unsecure_port)
+                host = "%s:%d" % (host, self.unsecure_port)
             else:
                 host = host.split(':')[0]
-                host = "%s:%d" % (host, args.unsecure_port)
-            args.content_addr = "http://%s" % (host,)
+                host = "%s:%d" % (host, self.unsecure_port)
+            content_addr = "http://%s" % (host,)
+
+        self.content_addr = content_addr
+
+    def default_config(self, config_dir_path, server_name):
+        if ":" in server_name:
+            bind_port = int(server_name.split(":")[1])
+            unsecure_port = bind_port - 400
+        else:
+            bind_port = 8448
+            unsecure_port = 8008
+
+        pid_file = self.abspath("homeserver.pid")
+        return """\
+        ## Server ##
+
+        # The domain name of the server, with optional explicit port.
+        # This is used by remote servers to connect to this server,
+        # e.g. matrix.org, localhost:8080, etc.
+        server_name: "%(server_name)s"
+
+        # The port to listen for HTTPS requests on.
+        # For when matrix traffic is sent directly to synapse.
+        bind_port: %(bind_port)s
 
-        self.content_addr = args.content_addr
+        # The port to listen for HTTP requests on.
+        # For when matrix traffic passes through loadbalancer that unwraps TLS.
+        unsecure_port: %(unsecure_port)s
+
+        # Local interface to listen on.
+        # The empty string will cause synapse to listen on all interfaces.
+        bind_host: ""
+
+        # When running as a daemon, the file to store the pid in
+        pid_file: %(pid_file)s
+
+        # Whether to serve a web client from the HTTP/HTTPS root resource.
+        web_client: True
+
+        # Set the soft limit on the number of file descriptors synapse can use
+        # Zero is used to indicate synapse should set the soft limit to the
+        # hard limit.
+        soft_file_limit: 0
+
+        # Turn on the twisted telnet manhole service on localhost on the given
+        # port.
+        #manhole: 9000
+        """ % locals()
+
+    def read_arguments(self, args):
+        if args.manhole is not None:
+            self.manhole = args.manhole
+        self.daemonize = args.daemonize
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(ServerConfig, cls).add_arguments(parser)
+    def add_arguments(self, parser):
         server_group = parser.add_argument_group("server")
-        server_group.add_argument(
-            "-H", "--server-name", default="localhost",
-            help="The domain name of the server, with optional explicit port. "
-                 "This is used by remote servers to connect to this server, "
-                 "e.g. matrix.org, localhost:8080, etc."
-        )
-        server_group.add_argument("-p", "--bind-port", metavar="PORT",
-                                  type=int, help="https port to listen on",
-                                  default=8448)
-        server_group.add_argument("--unsecure-port", metavar="PORT",
-                                  type=int, help="http port to listen on",
-                                  default=8008)
-        server_group.add_argument("--bind-host", default="",
-                                  help="Local interface to listen on")
         server_group.add_argument("-D", "--daemonize", action='store_true',
                                   help="Daemonize the home server")
-        server_group.add_argument('--pid-file', default="homeserver.pid",
-                                  help="When running as a daemon, the file to"
-                                  " store the pid in")
-        server_group.add_argument('--web_client', default=True, type=bool,
-                                  help="Whether or not to serve a web client")
         server_group.add_argument("--manhole", metavar="PORT", dest="manhole",
                                   type=int,
                                   help="Turn on the twisted telnet manhole"
                                   " service on the given port.")
-        server_group.add_argument("--content-addr", default=None,
-                                  help="The host and scheme to use for the "
-                                  "content repository")
-        server_group.add_argument("--soft-file-limit", type=int, default=0,
-                                  help="Set the soft limit on the number of "
-                                       "file descriptors synapse can use. "
-                                       "Zero is used to indicate synapse "
-                                       "should set the soft limit to the hard"
-                                       "limit.")
diff --git a/synapse/config/tls.py b/synapse/config/tls.py
index 034f9a7bf0..ecb2d42c1f 100644
--- a/synapse/config/tls.py
+++ b/synapse/config/tls.py
@@ -23,37 +23,44 @@ GENERATE_DH_PARAMS = False
 
 
 class TlsConfig(Config):
-    def __init__(self, args):
-        super(TlsConfig, self).__init__(args)
+    def read_config(self, config):
         self.tls_certificate = self.read_tls_certificate(
-            args.tls_certificate_path
+            config.get("tls_certificate_path")
         )
 
-        self.no_tls = args.no_tls
+        self.no_tls = config.get("no_tls", False)
 
         if self.no_tls:
             self.tls_private_key = None
         else:
             self.tls_private_key = self.read_tls_private_key(
-                args.tls_private_key_path
+                config.get("tls_private_key_path")
             )
 
         self.tls_dh_params_path = self.check_file(
-            args.tls_dh_params_path, "tls_dh_params"
+            config.get("tls_dh_params_path"), "tls_dh_params"
         )
 
-    @classmethod
-    def add_arguments(cls, parser):
-        super(TlsConfig, cls).add_arguments(parser)
-        tls_group = parser.add_argument_group("tls")
-        tls_group.add_argument("--tls-certificate-path",
-                               help="PEM encoded X509 certificate for TLS")
-        tls_group.add_argument("--tls-private-key-path",
-                               help="PEM encoded private key for TLS")
-        tls_group.add_argument("--tls-dh-params-path",
-                               help="PEM dh parameters for ephemeral keys")
-        tls_group.add_argument("--no-tls", action='store_true',
-                               help="Don't bind to the https port.")
+    def default_config(self, config_dir_path, server_name):
+        base_key_name = os.path.join(config_dir_path, server_name)
+
+        tls_certificate_path = base_key_name + ".tls.crt"
+        tls_private_key_path = base_key_name + ".tls.key"
+        tls_dh_params_path = base_key_name + ".tls.dh"
+
+        return """\
+        # PEM encoded X509 certificate for TLS
+        tls_certificate_path: "%(tls_certificate_path)s"
+
+        # PEM encoded private key for TLS
+        tls_private_key_path: "%(tls_private_key_path)s"
+
+        # PEM dh parameters for ephemeral keys
+        tls_dh_params_path: "%(tls_dh_params_path)s"
+
+        # Don't bind to the https port
+        no_tls: False
+        """ % locals()
 
     def read_tls_certificate(self, cert_path):
         cert_pem = self.read_file(cert_path, "tls_certificate")
@@ -63,22 +70,13 @@ class TlsConfig(Config):
         private_key_pem = self.read_file(private_key_path, "tls_private_key")
         return crypto.load_privatekey(crypto.FILETYPE_PEM, private_key_pem)
 
-    @classmethod
-    def generate_config(cls, args, config_dir_path):
-        super(TlsConfig, cls).generate_config(args, config_dir_path)
-        base_key_name = os.path.join(config_dir_path, args.server_name)
-
-        if args.tls_certificate_path is None:
-            args.tls_certificate_path = base_key_name + ".tls.crt"
-
-        if args.tls_private_key_path is None:
-            args.tls_private_key_path = base_key_name + ".tls.key"
-
-        if args.tls_dh_params_path is None:
-            args.tls_dh_params_path = base_key_name + ".tls.dh"
+    def generate_files(self, config):
+        tls_certificate_path = config["tls_certificate_path"]
+        tls_private_key_path = config["tls_private_key_path"]
+        tls_dh_params_path = config["tls_dh_params_path"]
 
-        if not os.path.exists(args.tls_private_key_path):
-            with open(args.tls_private_key_path, "w") as private_key_file:
+        if not os.path.exists(tls_private_key_path):
+            with open(tls_private_key_path, "w") as private_key_file:
                 tls_private_key = crypto.PKey()
                 tls_private_key.generate_key(crypto.TYPE_RSA, 2048)
                 private_key_pem = crypto.dump_privatekey(
@@ -86,17 +84,17 @@ class TlsConfig(Config):
                 )
                 private_key_file.write(private_key_pem)
         else:
-            with open(args.tls_private_key_path) as private_key_file:
+            with open(tls_private_key_path) as private_key_file:
                 private_key_pem = private_key_file.read()
                 tls_private_key = crypto.load_privatekey(
                     crypto.FILETYPE_PEM, private_key_pem
                 )
 
-        if not os.path.exists(args.tls_certificate_path):
-            with open(args.tls_certificate_path, "w") as certifcate_file:
+        if not os.path.exists(tls_certificate_path):
+            with open(tls_certificate_path, "w") as certifcate_file:
                 cert = crypto.X509()
                 subject = cert.get_subject()
-                subject.CN = args.server_name
+                subject.CN = config["server_name"]
 
                 cert.set_serial_number(1000)
                 cert.gmtime_adj_notBefore(0)
@@ -110,16 +108,16 @@ class TlsConfig(Config):
 
                 certifcate_file.write(cert_pem)
 
-        if not os.path.exists(args.tls_dh_params_path):
+        if not os.path.exists(tls_dh_params_path):
             if GENERATE_DH_PARAMS:
                 subprocess.check_call([
                     "openssl", "dhparam",
                     "-outform", "PEM",
-                    "-out", args.tls_dh_params_path,
+                    "-out", tls_dh_params_path,
                     "2048"
                 ])
             else:
-                with open(args.tls_dh_params_path, "w") as dh_params_file:
+                with open(tls_dh_params_path, "w") as dh_params_file:
                     dh_params_file.write(
                         "2048-bit DH parameters taken from rfc3526\n"
                         "-----BEGIN DH PARAMETERS-----\n"
diff --git a/synapse/config/voip.py b/synapse/config/voip.py
index 65162d21b7..a1707223d3 100644
--- a/synapse/config/voip.py
+++ b/synapse/config/voip.py
@@ -17,28 +17,21 @@ from ._base import Config
 
 class VoipConfig(Config):
 
-    def __init__(self, args):
-        super(VoipConfig, self).__init__(args)
-        self.turn_uris = args.turn_uris
-        self.turn_shared_secret = args.turn_shared_secret
-        self.turn_user_lifetime = args.turn_user_lifetime
-
-    @classmethod
-    def add_arguments(cls, parser):
-        super(VoipConfig, cls).add_arguments(parser)
-        group = parser.add_argument_group("voip")
-        group.add_argument(
-            "--turn-uris", type=str, default=None, action='append',
-            help="The public URIs of the TURN server to give to clients"
-        )
-        group.add_argument(
-            "--turn-shared-secret", type=str, default=None,
-            help=(
-                "The shared secret used to compute passwords for the TURN"
-                " server"
-            )
-        )
-        group.add_argument(
-            "--turn-user-lifetime", type=int, default=(1000 * 60 * 60),
-            help="How long generated TURN credentials last, in ms"
-        )
+    def read_config(self, config):
+        self.turn_uris = config.get("turn_uris", [])
+        self.turn_shared_secret = config["turn_shared_secret"]
+        self.turn_user_lifetime = self.parse_duration(config["turn_user_lifetime"])
+
+    def default_config(self, config_dir_path, server_name):
+        return """\
+        ## Turn ##
+
+        # The public URIs of the TURN server to give to clients
+        turn_uris: []
+
+        # The shared secret used to compute passwords for the TURN server
+        turn_shared_secret: "YOUR_SHARED_SECRET"
+
+        # How long generated TURN credentials last
+        turn_user_lifetime: "1h"
+        """