feat: accept redis client in rate limit RedisBackend

remoulade/rate_limits/backends/redis.py

@@ -25,8 +25,10 @@ class RedisBackend(RateLimitBackend):
     """Redis backend using ``limits`` RedisStorage.
 
     Parameters:
-      url(str): A redis connection URL.  If both a URL and
+      url(str): An optional connection URL.  If both a URL and
         connection parameters are provided, the URL is used.
+      client(Redis): An optional client.  If this is passed,
+        then all other parameters are ignored.
       key_prefix(str): A prefix to prepend to all keys used for rate limiting.
       strategy(str): The rate limiting strategy to use.  One of
         ``fixed_window``, ``moving_window``, or ``sliding_window``.
@@ -41,15 +43,21 @@ class RedisBackend(RateLimitBackend):
     def __init__(
         self,
         *,
-        url: str,
+        url: str | None = None,
+        client=None,
         key_prefix: str = "remoulade-rate-limit:",
         strategy: str = "sliding_window",
         **parameters,
     ):
         super().__init__()
 
+        if client is None and url is None:
+            raise ValueError("Either url or client must be provided")
+
         storage: Storage
-        if "sentinel" in url:
+        if client:
+            storage = RedisStorage("redis://localhost", connection_pool=client.connection_pool, key_prefix=key_prefix)
+        elif "sentinel" in url:
             storage = RedisSentinelStorage(url, key_prefix=key_prefix, **parameters)
         else:
             storage = RedisStorage(url, key_prefix=key_prefix, **parameters)

tests/conftest.py

@@ -174,10 +174,40 @@ def scheduler_thread():
 
 
 @pytest.fixture
-def rate_limit_backend():
+def stub_rate_limit_backend():
     return rl_backends.StubBackend()
 
 
+@pytest.fixture
+def redis_rate_limit_backend():
+    redis_url = os.getenv("REMOULADE_TEST_REDIS_URL") or "redis://localhost:6481/0"
+    client = redis.Redis.from_url(redis_url)
+    check_redis(client)
+    return rl_backends.RedisBackend(url=redis_url)
+
+
+@pytest.fixture
+def redis_rate_limit_backend_from_client():
+    redis_url = os.getenv("REMOULADE_TEST_REDIS_URL") or "redis://localhost:6481/0"
+    client = redis.Redis.from_url(redis_url)
+    check_redis(client)
+    return rl_backends.RedisBackend(client=client)
+
+
+@pytest.fixture
+def rate_limit_backends(stub_rate_limit_backend, redis_rate_limit_backend, redis_rate_limit_backend_from_client):
+    return {
+        "stub": stub_rate_limit_backend,
+        "redis": redis_rate_limit_backend,
+        "redis_client": redis_rate_limit_backend_from_client,
+    }
+
+
+@pytest.fixture(params=["stub", "redis", "redis_client"])
+def rate_limit_backend(request, rate_limit_backends):
+    return rate_limit_backends[request.param]
+
+
 @pytest.fixture
 def redis_result_backend():
     redis_url = os.getenv("REMOULADE_TEST_REDIS_URL") or "redis://localhost:6481/0"

tests/middleware/test_rate_limit.py

@@ -79,3 +79,10 @@ def do_work():
 def test_rate_limit_unknown_strategy():
     with pytest.raises(ValueError, match="Unknown rate limit strategy"):
         StubBackend(strategy="unknown")
+
+
+def test_redis_backend_requires_url_or_client():
+    from remoulade.rate_limits.backends import RedisBackend
+
+    with pytest.raises(ValueError, match="Either url or client must be provided"):
+        RedisBackend()