move from cronexpr to cronsim (#1)

* Replace cronexpr with cronsim for cron scheduling

The cronexpr package is replaced by cronsim for computing
next fire times. This also bumps the project version to
0.8.0, updates the build system requirement.

Author: Morry98

.pre-commit-config.yaml

@@ -32,7 +32,7 @@ repos:
     rev: v1.18.2
     hooks:
       - id: mypy
-        additional_dependencies: [ "types-redis", "fastapi", "pydantic"]
+        additional_dependencies: [ "types-redis", "fastapi", "pydantic", "cronsim"]
         args: ["--scripts-are-modules"]
 
   - repo: https://github.com/astral-sh/uv-pre-commit

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "fastapi-task-manager"
-version = "0.7.0"
+version = "0.8.0"
 description = "A task manager for Fastapi. Robust Scheduling, Distributed Safety"
 readme = "README.md"
 authors = [
@@ -31,14 +31,14 @@ classifiers = [
     "Operating System :: OS Independent",
 ]
 dependencies = [
-    "cronexpr>=0.30.0",
+    "cronsim>=2.7",
     "fastapi>=0.115.13",
     "pydantic>=2.11.7",
     "redis>=6.2.0",
 ]
 
 [build-system]
-requires = ["uv_build>=0.7.20,<0.9.0"]
+requires = ["uv_build>=0.9.0,<0.10.0"]
 build-backend = "uv_build"
 
 [[tool.uv.index]]

src/fastapi_task_manager/runner.py

@@ -6,7 +6,7 @@
 from typing import TYPE_CHECKING
 from uuid import uuid4
 
-from cronexpr import next_fire
+from cronsim import CronSim
 from redis.asyncio import Redis
 
 from fastapi_task_manager import TaskGroup
@@ -142,7 +142,9 @@ async def _run_task(self, task_group: TaskGroup, task: Task) -> None:  # noqa: P
             if redis_uuid_b.decode("utf-8") != self._uuid:
                 return
 
-            next_run = next_fire(task.expression)
+            local_date = datetime.now(timezone.utc)
+            next_run = next(CronSim(task.expression, local_date))
+
             await self._redis_client.set(
                 self._task_manager.config.app_name + "_" + task_group.name + "_" + task.name + "_next_run",
                 next_run.timestamp(),