feat(FN-004): merge fusion/fn-004

apps/api/app/main.py

@@ -1,22 +1,60 @@
+from collections.abc import AsyncGenerator
+from contextlib import asynccontextmanager
+
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.responses import JSONResponse
+from sqlalchemy import text
 
 from app.config import settings
+from app.db import AsyncSessionLocal, engine
+from app.routers import routers
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI) -> AsyncGenerator[None, None]:
+    async with AsyncSessionLocal() as session:
+        try:
+            await session.execute(text("SELECT 1"))
+        except Exception:
+            import logging
+            logging.getLogger(__name__).warning("Database connectivity check failed on startup")
+    yield
+    await engine.dispose()
+
 
 app = FastAPI(
     title=settings.app_name,
     debug=settings.debug,
+    lifespan=lifespan,
 )
 
+allow_origins = ["*"] if settings.debug else []
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=["http://localhost:5173"],
+    allow_origins=allow_origins,
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],
 )
 
+for router in routers:
+    app.include_router(router, prefix=settings.api_v1_prefix)
+
 
 @app.get("/health")
-def health() -> dict[str, str]:
-    return {"status": "ok", "service": settings.app_name}
+async def health() -> JSONResponse:
+    db_status = "connected"
+    try:
+        async with AsyncSessionLocal() as session:
+            await session.execute(text("SELECT 1"))
+    except Exception:
+        db_status = "unreachable"
+
+    content = {
+        "status": "ok" if db_status == "connected" else "degraded",
+        "service": settings.app_name,
+        "database": db_status,
+    }
+    status_code = 200 if db_status == "connected" else 503
+    return JSONResponse(status_code=status_code, content=content)