Revert "Allow for the configuration of max request retries and min/max retry delays in the matrix federation client (#12504)"

This reverts commit d84e66144dc12dacf71c987a2ba802dd59c0b68e.

5 files changed, 10 insertions, 68 deletions

diff --git a/CHANGES.md b/CHANGES.md
index 5412581eef..d898593664 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -30,7 +30,6 @@ Improved Documentation
 Internal Changes
 ----------------
 
-- Allow for the configuration of max request retries and min/max retry delays in the matrix federation client. ([\#12504](https://github.com/matrix-org/synapse/issues/12504))
 - Log when events are (maybe unexpectedly) filtered out of responses in tests. ([\#14213](https://github.com/matrix-org/synapse/issues/14213))
 - Read from column `full_user_id` rather than `user_id` of tables `profiles` and `user_filters`. ([\#15649](https://github.com/matrix-org/synapse/issues/15649))
 - Add support for tracing functions which return `Awaitable`s. ([\#15650](https://github.com/matrix-org/synapse/issues/15650))
diff --git a/docs/usage/configuration/config_documentation.md b/docs/usage/configuration/config_documentation.md
index 8426de0417..0cf6e075ff 100644
--- a/docs/usage/configuration/config_documentation.md
+++ b/docs/usage/configuration/config_documentation.md
@@ -1196,32 +1196,6 @@ Example configuration:
 allow_device_name_lookup_over_federation: true
 ```
 ---
-### `federation`
-
-The federation section defines some sub-options related to federation.
-
-The following options are related to configuring timeout and retry logic for one request,
-independently of the others.
-Short retry algorithm is used when something or someone will wait for the request to have an
-answer, while long retry is used for requests that happen in the background,
-like sending a federation transaction.
-
-* `client_timeout`: timeout for the federation requests in seconds. Default to 60s.
-* `max_short_retry_delay`: maximum delay to be used for the short retry algo in seconds. Default to 2s.
-* `max_long_retry_delay`: maximum delay to be used for the short retry algo in seconds. Default to 60s.
-* `max_short_retries`: maximum number of retries for the short retry algo. Default to 3 attempts.
-* `max_long_retries`: maximum number of retries for the long retry algo. Default to 10 attempts.
-
-Example configuration:
-```yaml
-federation:
-  client_timeout: 180
-  max_short_retry_delay: 7
-  max_long_retry_delay: 100
-  max_short_retries: 5
-  max_long_retries: 20
-```
----
 ## Caching
 
 Options related to caching.
diff --git a/synapse/config/federation.py b/synapse/config/federation.py
index d21f7fd02a..336fca578a 100644
--- a/synapse/config/federation.py
+++ b/synapse/config/federation.py
@@ -22,8 +22,6 @@ class FederationConfig(Config):
     section = "federation"
 
     def read_config(self, config: JsonDict, **kwargs: Any) -> None:
-        federation_config = config.setdefault("federation", {})
-
         # FIXME: federation_domain_whitelist needs sytests
         self.federation_domain_whitelist: Optional[dict] = None
         federation_domain_whitelist = config.get("federation_domain_whitelist", None)
@@ -51,13 +49,5 @@ class FederationConfig(Config):
             "allow_device_name_lookup_over_federation", False
         )
 
-        # Allow for the configuration of timeout, max request retries
-        # and min/max retry delays in the matrix federation client.
-        self.client_timeout = federation_config.get("client_timeout", 60)
-        self.max_long_retry_delay = federation_config.get("max_long_retry_delay", 60)
-        self.max_short_retry_delay = federation_config.get("max_short_retry_delay", 2)
-        self.max_long_retries = federation_config.get("max_long_retries", 10)
-        self.max_short_retries = federation_config.get("max_short_retries", 3)
-
 
 _METRICS_FOR_DOMAINS_SCHEMA = {"type": "array", "items": {"type": "string"}}
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index ed36825b67..abb5ae5815 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -95,6 +95,8 @@ incoming_responses_counter = Counter(
 )
 
 
+MAX_LONG_RETRIES = 10
+MAX_SHORT_RETRIES = 3
 MAXINT = sys.maxsize
 
 
@@ -404,12 +406,7 @@ class MatrixFederationHttpClient:
         self.clock = hs.get_clock()
         self._store = hs.get_datastores().main
         self.version_string_bytes = hs.version_string.encode("ascii")
-        self.default_timeout = hs.config.federation.client_timeout
-
-        self.max_long_retry_delay = hs.config.federation.max_long_retry_delay
-        self.max_short_retry_delay = hs.config.federation.max_short_retry_delay
-        self.max_long_retries = hs.config.federation.max_long_retries
-        self.max_short_retries = hs.config.federation.max_short_retries
+        self.default_timeout = 60
 
         self._cooperator = Cooperator(scheduler=_make_scheduler(self.reactor))
 
@@ -586,9 +583,9 @@ class MatrixFederationHttpClient:
             # XXX: Would be much nicer to retry only at the transaction-layer
             # (once we have reliable transactions in place)
             if long_retries:
-                retries_left = self.max_long_retries
+                retries_left = MAX_LONG_RETRIES
             else:
-                retries_left = self.max_short_retries
+                retries_left = MAX_SHORT_RETRIES
 
             url_bytes = request.uri
             url_str = url_bytes.decode("ascii")
@@ -733,12 +730,12 @@ class MatrixFederationHttpClient:
 
                     if retries_left and not timeout:
                         if long_retries:
-                            delay = 4 ** (self.max_long_retries + 1 - retries_left)
-                            delay = min(delay, self.max_long_retry_delay)
+                            delay = 4 ** (MAX_LONG_RETRIES + 1 - retries_left)
+                            delay = min(delay, 60)
                             delay *= random.uniform(0.8, 1.4)
                         else:
-                            delay = 0.5 * 2 ** (self.max_short_retries - retries_left)
-                            delay = min(delay, self.max_short_retry_delay)
+                            delay = 0.5 * 2 ** (MAX_SHORT_RETRIES - retries_left)
+                            delay = min(delay, 2)
                             delay *= random.uniform(0.8, 1.4)
 
                         logger.debug(
diff --git a/tests/http/test_matrixfederationclient.py b/tests/http/test_matrixfederationclient.py
index 8565f8ac64..0dfc03ce50 100644
--- a/tests/http/test_matrixfederationclient.py
+++ b/tests/http/test_matrixfederationclient.py
@@ -40,7 +40,7 @@ from synapse.server import HomeServer
 from synapse.util import Clock
 
 from tests.server import FakeTransport
-from tests.unittest import HomeserverTestCase, override_config
+from tests.unittest import HomeserverTestCase
 
 
 def check_logcontext(context: LoggingContextOrSentinel) -> None:
@@ -640,21 +640,3 @@ class FederationClientTests(HomeserverTestCase):
             self.cl.build_auth_headers(
                 b"", b"GET", b"https://example.com", destination_is=b""
             )
-
-    @override_config(
-        {
-            "federation": {
-                "client_timeout": 180,
-                "max_long_retry_delay": 100,
-                "max_short_retry_delay": 7,
-                "max_long_retries": 20,
-                "max_short_retries": 5,
-            }
-        }
-    )
-    def test_configurable_retry_and_delay_values(self) -> None:
-        self.assertEqual(self.cl.default_timeout, 180)
-        self.assertEqual(self.cl.max_long_retry_delay, 100)
-        self.assertEqual(self.cl.max_short_retry_delay, 7)
-        self.assertEqual(self.cl.max_long_retries, 20)
-        self.assertEqual(self.cl.max_short_retries, 5)