app/core/app.py

"""Fábrica de la aplicación FastAPI."""

from __future__ import annotations

from fastapi import FastAPI

from app.core.config import settings
from app.core.exception_handlers import register_exception_handlers
from app.core.lifespan import lifespan
from app.core.middleware import setup_middlewares
from app.rutas import api_router


def create_app() -> FastAPI:
    """Crea y configura la instancia de FastAPI."""
    app = FastAPI(
        title=settings.APP_NAME,
        version=settings.APP_VERSION,
        description=settings.APP_DESCRIPTION,
        debug=settings.DEBUG,
        lifespan=lifespan,
    )

    setup_middlewares(app)
    register_exception_handlers(app)
    app.include_router(api_router, prefix=settings.API_PREFIX)

    @app.get("/health", tags=["Salud"], summary="Estado del servicio")
    async def health() -> dict[str, str]:
        """Liveness: responde siempre y rápido (no depende de la base de datos)."""
        return {"status": "ok"}

    @app.get(
        "/health/db",
        tags=["Salud"],
        summary="Estado de la conexión a MongoDB",
    )
    async def health_db() -> dict[str, str]:
        """Readiness: comprueba si MongoDB responde en este momento."""
        from app.database.mongodb import mongodb

        conectado = await mongodb.ping()
        return {"database": "connected" if conectado else "disconnected"}

    return app