Make all the rate limiting options more consistent (#5181)

5 files changed, 104 insertions, 91 deletions

diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 5a68399e63..5a9adac480 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -16,16 +16,56 @@ from ._base import Config
 
 
 class RateLimitConfig(object):
-    def __init__(self, config):
-        self.per_second = config.get("per_second", 0.17)
-        self.burst_count = config.get("burst_count", 3.0)
+    def __init__(self, config, defaults={"per_second": 0.17, "burst_count": 3.0}):
+        self.per_second = config.get("per_second", defaults["per_second"])
+        self.burst_count = config.get("burst_count", defaults["burst_count"])
 
 
-class RatelimitConfig(Config):
+class FederationRateLimitConfig(object):
+    _items_and_default = {
+        "window_size": 10000,
+        "sleep_limit": 10,
+        "sleep_delay": 500,
+        "reject_limit": 50,
+        "concurrent": 3,
+    }
+
+    def __init__(self, **kwargs):
+        for i in self._items_and_default.keys():
+            setattr(self, i, kwargs.get(i) or self._items_and_default[i])
+
 
+class RatelimitConfig(Config):
     def read_config(self, config):
-        self.rc_messages_per_second = config.get("rc_messages_per_second", 0.2)
-        self.rc_message_burst_count = config.get("rc_message_burst_count", 10.0)
+
+        # Load the new-style messages config if it exists. Otherwise fall back
+        # to the old method.
+        if "rc_message" in config:
+            self.rc_message = RateLimitConfig(
+                config["rc_message"], defaults={"per_second": 0.2, "burst_count": 10.0}
+            )
+        else:
+            self.rc_message = RateLimitConfig(
+                {
+                    "per_second": config.get("rc_messages_per_second", 0.2),
+                    "burst_count": config.get("rc_message_burst_count", 10.0),
+                }
+            )
+
+        # Load the new-style federation config, if it exists. Otherwise, fall
+        # back to the old method.
+        if "federation_rc" in config:
+            self.rc_federation = FederationRateLimitConfig(**config["rc_federation"])
+        else:
+            self.rc_federation = FederationRateLimitConfig(
+                **{
+                    "window_size": config.get("federation_rc_window_size"),
+                    "sleep_limit": config.get("federation_rc_sleep_limit"),
+                    "sleep_delay": config.get("federation_rc_sleep_delay"),
+                    "reject_limit": config.get("federation_rc_reject_limit"),
+                    "concurrent": config.get("federation_rc_concurrent"),
+                }
+            )
 
         self.rc_registration = RateLimitConfig(config.get("rc_registration", {}))
 
@@ -33,38 +73,26 @@ class RatelimitConfig(Config):
         self.rc_login_address = RateLimitConfig(rc_login_config.get("address", {}))
         self.rc_login_account = RateLimitConfig(rc_login_config.get("account", {}))
         self.rc_login_failed_attempts = RateLimitConfig(
-            rc_login_config.get("failed_attempts", {}),
+            rc_login_config.get("failed_attempts", {})
         )
 
-        self.federation_rc_window_size = config.get("federation_rc_window_size", 1000)
-        self.federation_rc_sleep_limit = config.get("federation_rc_sleep_limit", 10)
-        self.federation_rc_sleep_delay = config.get("federation_rc_sleep_delay", 500)
-        self.federation_rc_reject_limit = config.get("federation_rc_reject_limit", 50)
-        self.federation_rc_concurrent = config.get("federation_rc_concurrent", 3)
-
         self.federation_rr_transactions_per_room_per_second = config.get(
-            "federation_rr_transactions_per_room_per_second", 50,
+            "federation_rr_transactions_per_room_per_second", 50
         )
 
     def default_config(self, **kwargs):
         return """\
         ## Ratelimiting ##
 
-        # Number of messages a client can send per second
-        #
-        #rc_messages_per_second: 0.2
-
-        # Number of message a client can send before being throttled
-        #
-        #rc_message_burst_count: 10.0
-
-        # Ratelimiting settings for registration and login.
+        # Ratelimiting settings for client actions (registration, login, messaging).
         #
         # Each ratelimiting configuration is made of two parameters:
         #   - per_second: number of requests a client can send per second.
         #   - burst_count: number of requests a client can send before being throttled.
         #
         # Synapse currently uses the following configurations:
+        #   - one for messages that ratelimits sending based on the account the client
+        #     is using
         #   - one for registration that ratelimits registration requests based on the
         #     client's IP address.
         #   - one for login that ratelimits login requests based on the client's IP
@@ -77,6 +105,10 @@ class RatelimitConfig(Config):
         #
         # The defaults are as shown below.
         #
+        #rc_message:
+        #  per_second: 0.2
+        #  burst_count: 10
+        #
         #rc_registration:
         #  per_second: 0.17
         #  burst_count: 3
@@ -92,29 +124,28 @@ class RatelimitConfig(Config):
         #    per_second: 0.17
         #    burst_count: 3
 
-        # The federation window size in milliseconds
-        #
-        #federation_rc_window_size: 1000
-
-        # 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
 
-        # The duration in milliseconds to delay processing events from
-        # remote servers by if they go over the sleep limit.
+        # Ratelimiting settings for incoming federation
         #
-        #federation_rc_sleep_delay: 500
-
-        # The maximum number of concurrent federation requests allowed
-        # from a single server
+        # The rc_federation configuration is made up of the following settings:
+        #   - window_size: window size in milliseconds
+        #   - sleep_limit: number of federation requests from a single server in
+        #     a window before the server will delay processing the request.
+        #   - sleep_delay: duration in milliseconds to delay processing events
+        #     from remote servers by if they go over the sleep limit.
+        #   - reject_limit: maximum number of concurrent federation requests
+        #     allowed from a single server
+        #   - concurrent: number of federation requests to concurrently process
+        #     from a single server
         #
-        #federation_rc_reject_limit: 50
-
-        # The number of federation requests to concurrently process from a
-        # single server
+        # The defaults are as shown below.
         #
-        #federation_rc_concurrent: 3
+        #rc_federation:
+        #  window_size: 1000
+        #  sleep_limit: 10
+        #  sleep_delay: 500
+        #  reject_limit: 50
+        #  concurrent: 3
 
         # Target outgoing federation transaction frequency for sending read-receipts,
         # per-room.
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 9030eb18c5..385eda2dca 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -63,11 +63,7 @@ class TransportLayerServer(JsonResource):
         self.authenticator = Authenticator(hs)
         self.ratelimiter = FederationRateLimiter(
             self.clock,
-            window_size=hs.config.federation_rc_window_size,
-            sleep_limit=hs.config.federation_rc_sleep_limit,
-            sleep_msec=hs.config.federation_rc_sleep_delay,
-            reject_limit=hs.config.federation_rc_reject_limit,
-            concurrent_requests=hs.config.federation_rc_concurrent,
+            config=hs.config.rc_federation,
         )
 
         self.register_servlets()
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index ac09d03ba9..dca337ec61 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -90,8 +90,8 @@ class BaseHandler(object):
             messages_per_second = override.messages_per_second
             burst_count = override.burst_count
         else:
-            messages_per_second = self.hs.config.rc_messages_per_second
-            burst_count = self.hs.config.rc_message_burst_count
+            messages_per_second = self.hs.config.rc_message.per_second
+            burst_count = self.hs.config.rc_message.burst_count
 
         allowed, time_allowed = self.ratelimiter.can_do_action(
             user_id, time_now,
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index dc3e265bcd..3d045880b9 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -31,6 +31,7 @@ from synapse.api.errors import (
     SynapseError,
     UnrecognizedRequestError,
 )
+from synapse.config.ratelimiting import FederationRateLimitConfig
 from synapse.config.server import is_threepid_reserved
 from synapse.http.servlet import (
     RestServlet,
@@ -153,16 +154,18 @@ class UsernameAvailabilityRestServlet(RestServlet):
         self.registration_handler = hs.get_registration_handler()
         self.ratelimiter = FederationRateLimiter(
             hs.get_clock(),
-            # Time window of 2s
-            window_size=2000,
-            # Artificially delay requests if rate > sleep_limit/window_size
-            sleep_limit=1,
-            # Amount of artificial delay to apply
-            sleep_msec=1000,
-            # Error with 429 if more than reject_limit requests are queued
-            reject_limit=1,
-            # Allow 1 request at a time
-            concurrent_requests=1,
+            FederationRateLimitConfig(
+                # Time window of 2s
+                window_size=2000,
+                # Artificially delay requests if rate > sleep_limit/window_size
+                sleep_limit=1,
+                # Amount of artificial delay to apply
+                sleep_msec=1000,
+                # Error with 429 if more than reject_limit requests are queued
+                reject_limit=1,
+                # Allow 1 request at a time
+                concurrent_requests=1,
+            )
         )
 
     @defer.inlineCallbacks
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index 7deb38f2a7..b146d137f4 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -30,31 +30,14 @@ logger = logging.getLogger(__name__)
 
 
 class FederationRateLimiter(object):
-    def __init__(self, clock, window_size, sleep_limit, sleep_msec,
-                 reject_limit, concurrent_requests):
+    def __init__(self, clock, config):
         """
         Args:
             clock (Clock)
-            window_size (int): The window size in milliseconds.
-            sleep_limit (int): The number of requests received in the last
-                `window_size` milliseconds before we artificially start
-                delaying processing of requests.
-            sleep_msec (int): The number of milliseconds to delay processing
-                of incoming requests by.
-            reject_limit (int): The maximum number of requests that are can be
-                queued for processing before we start rejecting requests with
-                a 429 Too Many Requests response.
-            concurrent_requests (int): The number of concurrent requests to
-                process.
+            config (FederationRateLimitConfig)
         """
         self.clock = clock
-
-        self.window_size = window_size
-        self.sleep_limit = sleep_limit
-        self.sleep_msec = sleep_msec
-        self.reject_limit = reject_limit
-        self.concurrent_requests = concurrent_requests
-
+        self._config = config
         self.ratelimiters = {}
 
     def ratelimit(self, host):
@@ -76,25 +59,25 @@ class FederationRateLimiter(object):
             host,
             _PerHostRatelimiter(
                 clock=self.clock,
-                window_size=self.window_size,
-                sleep_limit=self.sleep_limit,
-                sleep_msec=self.sleep_msec,
-                reject_limit=self.reject_limit,
-                concurrent_requests=self.concurrent_requests,
+                config=self._config,
             )
         ).ratelimit()
 
 
 class _PerHostRatelimiter(object):
-    def __init__(self, clock, window_size, sleep_limit, sleep_msec,
-                 reject_limit, concurrent_requests):
+    def __init__(self, clock, config):
+        """
+        Args:
+            clock (Clock)
+            config (FederationRateLimitConfig)
+        """
         self.clock = clock
 
-        self.window_size = window_size
-        self.sleep_limit = sleep_limit
-        self.sleep_sec = sleep_msec / 1000.0
-        self.reject_limit = reject_limit
-        self.concurrent_requests = concurrent_requests
+        self.window_size = config.window_size
+        self.sleep_limit = config.sleep_limit
+        self.sleep_sec = config.sleep_delay / 1000.0
+        self.reject_limit = config.reject_limit
+        self.concurrent_requests = config.concurrent
 
         # request_id objects for requests which have been slept
         self.sleeping_requests = set()