decomposer: generate files for Maintain only the latest check result for each monitored target in concurrency-safe memory and expose it through the specified FastAPI current-status endpoint.

tests/test_concurrency.py

@@ -0,0 +1,56 @@
+import asyncio
+
+from current_status import CurrentStatusCoordinator
+
+
+async def test_older_overlapping_check_cannot_replace_newer_check() -> None:
+    coordinator = CurrentStatusCoordinator()
+    await coordinator.register_target("t")
+    release_old = asyncio.Event()
+
+    async def old(_target):
+        await release_old.wait()
+        return {"value": "old"}
+
+    async def new(_target):
+        return {"value": "new"}
+
+    old_task = asyncio.create_task(coordinator.run_check("t", {}, old))
+    await asyncio.sleep(0)
+    assert await coordinator.run_check("t", {}, new) is True
+    release_old.set()
+    assert await old_task is False
+    exists, status = await coordinator.read("t")
+    assert exists and status is not None
+    assert status["payload"] == {"value": "new"}
+    assert await coordinator.retained_status_count() == 1
+
+
+async def test_delete_cleans_status_and_stale_check_cannot_resurrect_recreate() -> None:
+    coordinator = CurrentStatusCoordinator()
+    await coordinator.register_target("same-id")
+
+    async def initial(_target):
+        return {"value": "initial"}
+
+    assert await coordinator.run_check("same-id", {}, initial)
+    assert await coordinator.retained_status_count() == 1
+
+    release = asyncio.Event()
+
+    async def stale(_target):
+        await release.wait()
+        return {"value": "stale"}
+
+    stale_task = asyncio.create_task(coordinator.run_check("same-id", {}, stale))
+    await asyncio.sleep(0)
+    assert await coordinator.delete_target("same-id")
+    assert await coordinator.retained_status_count() == 0
+    await coordinator.register_target("same-id")
+    release.set()
+
+    assert await stale_task is False
+    exists, status = await coordinator.read("same-id")
+    assert exists is True
+    assert status is None
+    assert await coordinator.retained_status_count() == 0