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.

src/current_status/api.py

@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+from typing import Any, Literal
+
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel
+
+from .coordinator import CurrentStatusCoordinator
+
+
+class CheckResult(BaseModel):
+    payload: dict[str, Any]
+    checked_at: str
+    check_sequence: int
+
+
+class CurrentStatusResponse(BaseModel):
+    target_id: str
+    state: Literal["not_checked", "checked"]
+    result: CheckResult | None
+
+
+def build_current_status_router(coordinator: CurrentStatusCoordinator) -> APIRouter:
+    router = APIRouter()
+
+    @router.get(
+        "/targets/{target_id}/status",
+        response_model=CurrentStatusResponse,
+        responses={404: {"description": "Target does not exist"}},
+    )
+    async def get_current_status(target_id: str) -> dict[str, Any]:
+        exists, result = await coordinator.read(target_id)
+        if not exists:
+            raise HTTPException(
+                status_code=404,
+                detail={"code": "target_not_found", "target_id": target_id},
+            )
+        return {
+            "target_id": target_id,
+            "state": "checked" if result is not None else "not_checked",
+            "result": result,
+        }
+
+    return router