decomposer: generate deliverable files for Define the service contract and project architecture for the FastAPI endpoint monitoring service.; Implement the typed monitor CRUD API and concurrency-safe in-memory state according to the service design.; Implement secure on-demand endpoint checks with status updates, latency measurement, robust error handling, and redacted structured logs.; Add operational API endpoints and environment-driven runtime configuration to the monitoring service.; Create automated tests for the monitoring service.; Package the service with Docker and developer documentation.; Validate the complete project.

app/store.py

@@ -1,68 +1,53 @@
 import asyncio
 from dataclasses import dataclass
-from datetime import datetime, timezone
 from uuid import UUID, uuid4
 
-from app.models import CheckStatus, Monitor, MonitorCreate, MonitorUpdate
-
-
-@dataclass(frozen=True)
-class Snapshot:
-    monitor: Monitor
-    revision: int
+from .models import CheckResult, Monitor, MonitorCreate, MonitorStatus, MonitorUpdate, utcnow
 
 
+@dataclass
 class MonitorStore:
-    def __init__(self) -> None:
+    def __post_init__(self) -> None:
+        self._items: dict[UUID, Monitor] = {}
         self._lock = asyncio.Lock()
-        self._items: dict[UUID, tuple[Monitor, int]] = {}
 
     async def create(self, data: MonitorCreate) -> Monitor:
-        now = datetime.now(timezone.utc)
-        item = Monitor(id=uuid4(), name=data.name, url=data.url, created_at=now,
-                       updated_at=now, status=CheckStatus())
+        now = utcnow()
+        item = Monitor(id=uuid4(), name=data.name, url=data.url, created_at=now, updated_at=now)
         async with self._lock:
-            self._items[item.id] = (item, 1)
-        return item.model_copy(deep=True)
+            self._items[item.id] = item
+        return item
 
     async def list(self) -> list[Monitor]:
         async with self._lock:
-            values = [item.model_copy(deep=True) for item, _ in self._items.values()]
-        return sorted(values, key=lambda item: (item.created_at, str(item.id)))
+            return sorted(self._items.values(), key=lambda item: (item.created_at, str(item.id)))
 
-    async def snapshot(self, monitor_id: UUID) -> Snapshot | None:
+    async def get(self, monitor_id: UUID) -> Monitor | None:
         async with self._lock:
-            stored = self._items.get(monitor_id)
-            if stored is None:
-                return None
-            item, revision = stored
-            return Snapshot(item.model_copy(deep=True), revision)
+            return self._items.get(monitor_id)
 
     async def update(self, monitor_id: UUID, data: MonitorUpdate) -> Monitor | None:
         async with self._lock:
-            stored = self._items.get(monitor_id)
-            if stored is None:
+            current = self._items.get(monitor_id)
+            if current is None:
                 return None
-            item, revision = stored
-            changes = data.model_dump(exclude_none=True)
-            if "url" in changes:
-                changes["status"] = CheckStatus()
-            changes["updated_at"] = datetime.now(timezone.utc)
-            updated = item.model_copy(update=changes)
-            self._items[monitor_id] = (updated, revision + 1)
-            return updated.model_copy(deep=True)
+            updated = current.model_copy(update={
+                "name": data.name, "url": data.url, "updated_at": utcnow(),
+                "status": MonitorStatus.unknown, "checked_at": None,
+                "latency_ms": None, "http_status": None, "error": None,
+            })
+            self._items[monitor_id] = updated
+            return updated
 
     async def delete(self, monitor_id: UUID) -> bool:
         async with self._lock:
             return self._items.pop(monitor_id, None) is not None
 
-    async def apply_status(self, monitor_id: UUID, revision: int,
-                           status: CheckStatus) -> bool:
+    async def record(self, monitor_id: UUID, result: CheckResult) -> Monitor | None:
         async with self._lock:
-            stored = self._items.get(monitor_id)
-            if stored is None or stored[1] != revision:
-                return False
-            item, current_revision = stored
-            updated = item.model_copy(update={"status": status})
-            self._items[monitor_id] = (updated, current_revision)
-            return True
+            current = self._items.get(monitor_id)
+            if current is None:
+                return None
+            updated = current.model_copy(update={**result.model_dump(), "updated_at": utcnow()})
+            self._items[monitor_id] = updated
+            return updated