Version 1.0.2

README.md

@@ -50,8 +50,8 @@ except DuplicateTaskError:
 
 ## Features
 
-- **Sender-side deduplication** — rejects duplicate tasks at dispatch time via a Redis queue lock, before they reach the broker.
+- **Sender-side deduplication** — rejects duplicate tasks at dispatch time via a Redis lock, before they reach the broker.
-- **Worker-side detection** — logs concurrent duplicate executions without raising, keeping `SmartRetryMiddleware` safe from retry storms.
+- **Atomic lock release** — lock is released on completion or error via a Lua check-and-delete; only the owning task can release its lock.
 - **Configurable TTL** — set a global default or override per task with the `deduplication_ttl` label.
 - **Explicit lock key** — pin any task to a fixed Redis key with `deduplication_key`, bypassing fingerprint computation entirely.
 - **Partial fingerprint** — deduplicate on a subset of kwargs with `deduplication_key_fields`, ignoring irrelevant arguments.

docs/index.md

@@ -50,8 +50,8 @@ except DuplicateTaskError:
 
 ## Features
 
-- **Sender-side deduplication** — rejects duplicate tasks at dispatch time via a Redis queue lock, before they reach the broker.
+- **Sender-side deduplication** — rejects duplicate tasks at dispatch time via a Redis lock, before they reach the broker.
-- **Worker-side detection** — logs concurrent duplicate executions without raising, keeping `SmartRetryMiddleware` safe from retry storms.
+- **Atomic lock release** — lock is released on completion or error via a Lua check-and-delete; only the owning task can release its lock.
 - **Configurable TTL** — set a global default or override per task with the `deduplication_ttl` label.
 - **Explicit lock key** — pin any task to a fixed Redis key with `deduplication_key`, bypassing fingerprint computation entirely.
 - **Partial fingerprint** — deduplicate on a subset of kwargs with `deduplication_key_fields`, ignoring irrelevant arguments.

pyproject.toml

@@ -1,7 +1,7 @@
 [project]
 name = "taskiq-deduplication"
-version = "1.0.1"
+version = "1.0.2"
-description = "Production-ready utilities for FastAPI applications"
+description = "Redis-backed deduplication middleware for Taskiq"
 readme = "README.md"
 license = "MIT"
 license-files = ["LICENSE"]
@@ -9,7 +9,7 @@ requires-python = ">=3.10"
 authors = [
     { name = "d3vyce", email = "contact@d3vyce.fr" }
 ]
-keywords = ["fastapi", "sqlalchemy", "postgresql"]
+keywords = ["taskiq", "redis", "deduplication", "middleware", "task-queue"]
 classifiers = [
     "Development Status :: 5 - Production/Stable",
     "Framework :: AsyncIO",

src/taskiq_deduplication/__init__.py

@@ -1,8 +1,8 @@
-"""FastAPI utilities package."""
+"""Redis-backed deduplication middleware for Taskiq."""
 
 from .middleware import DuplicateTaskError, RedisDeduplicationMiddleware
 
-__version__ = "1.0.1"
+__version__ = "1.0.2"
 
 __all__ = [
     "DuplicateTaskError",

src/taskiq_deduplication/middleware.py

@@ -56,7 +56,7 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
         if self._redis is not None:
             await self._redis.aclose()
 
-    def _build_deduplication_key(self, message: TaskiqMessage) -> str:
+    def _build_deduplication_key(self, message: TaskiqMessage) -> str | None:
         explicit_key: str | None = message.labels.get(DEDUP_EXPLICIT_KEY_LABEL)
         if explicit_key is not None:
             return f"{self.key_prefix}:{explicit_key}"
@@ -67,10 +67,13 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
             if key_fields is not None
             else message.kwargs
         )
-        payload = json.dumps(
+        try:
-            {"task": message.task_name, "kwargs": kwargs},
+            payload = json.dumps(
-            sort_keys=True,
+                {"task": message.task_name, "kwargs": kwargs},
-        )
+                sort_keys=True,
+            )
+        except TypeError:
+            return None
         fingerprint = hashlib.sha256(payload.encode()).hexdigest()[:16]
         return f"{self.key_prefix}:{fingerprint}"
 
@@ -81,7 +84,10 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
         return int(labels.get(DEDUP_TTL_LABEL, self.default_ttl))
 
     async def _release_if_owned(self, key: str, task_id: str) -> None:
-        assert self._redis is not None
+        if self._redis is None:
+            raise RuntimeError(
+                "RedisDeduplicationMiddleware.startup() was never called."
+            )
         released = await check_and_delete(self._redis, key, task_id)
         if released:
             logger.debug("Released lock %s", key)
@@ -92,8 +98,18 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
         if not self._is_enabled(message.labels):
             return message
 
-        assert self._redis is not None
+        if self._redis is None:
+            raise RuntimeError(
+                "RedisDeduplicationMiddleware.startup() was never called."
+            )
         key = self._build_deduplication_key(message)
+        if key is None:
+            logger.warning(
+                "Task %s has non-JSON-serializable kwargs; deduplication skipped."
+                " Use the deduplication_key label to deduplicate this task.",
+                message.task_name,
+            )
+            return message
         ttl = self._get_ttl(message.labels)
 
         logger.debug("Acquiring lock %s for task %s", key, message.task_name)
@@ -118,9 +134,10 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
     ) -> None:
         if not self._is_enabled(message.labels):
             return
-        await self._release_if_owned(
+        key = self._build_deduplication_key(message)
-            self._build_deduplication_key(message), message.task_id
+        if key is None:
-        )
+            return
+        await self._release_if_owned(key, message.task_id)
 
     async def on_error(
         self,
@@ -130,6 +147,7 @@ class RedisDeduplicationMiddleware(TaskiqMiddleware):
     ) -> None:
         if not self._is_enabled(message.labels):
             return
-        await self._release_if_owned(
+        key = self._build_deduplication_key(message)
-            self._build_deduplication_key(message), message.task_id
+        if key is None:
-        )
+            return
+        await self._release_if_owned(key, message.task_id)

tests/test_middleware.py

@@ -92,7 +92,45 @@ class TestDefaultBuildDeduplicationKey:
         mw._redis = None
         m = make_message()
         key = mw._build_deduplication_key(m)
-        assert key.startswith("myapp:locks:")
+        assert key is not None and key.startswith("myapp:locks:")
+
+    def test_empty_kwargs_produces_consistent_key(self, middleware, make_message):
+        m1 = make_message(kwargs={})
+        m2 = make_message(kwargs={})
+        assert middleware._build_deduplication_key(
+            m1
+        ) == middleware._build_deduplication_key(m2)
+
+    def test_key_fields_empty_list_ignores_all_kwargs(self, middleware, make_message):
+        m1 = make_message(kwargs={"a": 1}, labels={DEDUP_KEY_FIELDS_LABEL: []})
+        m2 = make_message(kwargs={"a": 999}, labels={DEDUP_KEY_FIELDS_LABEL: []})
+        assert middleware._build_deduplication_key(
+            m1
+        ) == middleware._build_deduplication_key(m2)
+
+    def test_key_fields_absent_from_kwargs_are_ignored(self, middleware, make_message):
+        m1 = make_message(
+            kwargs={"order_id": 1}, labels={DEDUP_KEY_FIELDS_LABEL: ["user_id"]}
+        )
+        m2 = make_message(
+            kwargs={"order_id": 999}, labels={DEDUP_KEY_FIELDS_LABEL: ["user_id"]}
+        )
+        assert middleware._build_deduplication_key(
+            m1
+        ) == middleware._build_deduplication_key(m2)
+
+    def test_explicit_key_takes_precedence_over_key_fields(
+        self, middleware, make_message
+    ):
+        m = make_message(
+            kwargs={"a": 1},
+            labels={DEDUP_EXPLICIT_KEY_LABEL: "my-lock", DEDUP_KEY_FIELDS_LABEL: ["a"]},
+        )
+        assert middleware._build_deduplication_key(m) == "taskiq:deduplication:my-lock"
+
+    def test_non_serializable_kwargs_returns_none(self, middleware, make_message):
+        m = make_message(kwargs={"dt": object()})
+        assert middleware._build_deduplication_key(m) is None
 
 
 class TestPreSend:
@@ -140,6 +178,25 @@ class TestPreSend:
         await middleware.pre_send(make_message(kwargs={"x": 1}))
         await middleware.pre_send(make_message(kwargs={"x": 2}))
 
+    @pytest.mark.anyio
+    async def test_non_serializable_kwargs_skips_deduplication(
+        self, middleware, make_message
+    ):
+        msg1 = make_message(kwargs={"dt": object()})
+        msg2 = make_message(kwargs={"dt": object()})
+        await middleware.pre_send(msg1)
+        await middleware.pre_send(msg2)  # should not raise
+
+    @pytest.mark.anyio
+    async def test_default_ttl_applied(self, fake_redis, make_message):
+        mw = RedisDeduplicationMiddleware(redis_url="redis://localhost", default_ttl=77)
+        mw._redis = fake_redis
+        msg = make_message()
+        await mw.pre_send(msg)
+        key = mw._build_deduplication_key(msg)
+        ttl = await fake_redis.ttl(key)
+        assert 0 < ttl <= 77
+
 
 class TestPostExecute:
     @pytest.mark.anyio
@@ -166,6 +223,15 @@ class TestPostExecute:
         await middleware.post_execute(disabled_msg, make_result())
         assert await fake_redis.exists(key)
 
+    @pytest.mark.anyio
+    async def test_post_execute_after_ttl_expiry_is_safe(
+        self, middleware, fake_redis, make_message, make_result
+    ):
+        msg = make_message()
+        await middleware.pre_send(msg)
+        await fake_redis.delete(middleware._build_deduplication_key(msg))
+        await middleware.post_execute(msg, make_result())
+
 
 class TestOnError:
     @pytest.mark.anyio
@@ -195,6 +261,26 @@ class TestOnError:
         assert await fake_redis.exists(key)
 
 
+class TestRedispatchAfterRelease:
+    @pytest.mark.anyio
+    async def test_redispatch_after_post_execute(
+        self, middleware, make_message, make_result
+    ):
+        msg = make_message()
+        await middleware.pre_send(msg)
+        await middleware.post_execute(msg, make_result())
+        await middleware.pre_send(make_message())
+
+    @pytest.mark.anyio
+    async def test_redispatch_after_on_error(
+        self, middleware, make_message, make_result
+    ):
+        msg = make_message()
+        await middleware.pre_send(msg)
+        await middleware.on_error(msg, make_result(is_err=True), RuntimeError("boom"))
+        await middleware.pre_send(make_message())
+
+
 class TestAtomicRelease:
     @pytest.mark.anyio
     async def test_only_owner_can_release(self, middleware, fake_redis, make_message):
@@ -240,3 +326,9 @@ class TestLifecycle:
     async def test_shutdown_without_startup_is_safe(self):
         mw = RedisDeduplicationMiddleware(redis_url="redis://localhost")
         await mw.shutdown()
+
+    @pytest.mark.anyio
+    async def test_pre_send_without_startup_raises_runtime_error(self, make_message):
+        mw = RedisDeduplicationMiddleware(redis_url="redis://localhost")
+        with pytest.raises(RuntimeError, match="startup"):
+            await mw.pre_send(make_message())

uv.lock

@@ -1468,7 +1468,7 @@ wheels = [
 
 [[package]]
 name = "taskiq-deduplication"
-version = "1.0.1"
+version = "1.0.2"
 source = { editable = "." }
 dependencies = [
     { name = "redis" },