xian_algorithm_new/app/core/server.py

"""
FastAPI 服务创建与配置
"""
import time
from contextlib import asynccontextmanager

from fastapi import FastAPI, Request

from app.utils.api_deps import get_rainfall_model, get_earthquake_model
from app.config.paths import get_logger
from config import settings

logger = get_logger("api")


@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期：启动时预加载 DBN 模型"""
    logger.info("正在预加载DBN模型...")
    get_rainfall_model()
    get_earthquake_model()
    logger.info("DBN模型预加载完成")

    # 检测 Docker QGIS 容器是否可用
    try:
        import subprocess
        from app.services.qgis.qgis_env import get_docker_container
        container = get_docker_container()
        result = subprocess.run(
            ["docker", "inspect", "--format={{.State.Running}}", container],
            capture_output=True, text=True, timeout=5,
        )
        if result.stdout.strip() == "true":
            logger.info(f"Docker QGIS 容器 '{container}' 运行中")
        else:
            logger.warning(f"Docker QGIS 容器 '{container}' 未运行，专题图功能降级")
    except Exception as e:
        logger.error(f"Docker QGIS 检测失败: {e}")

    yield

    logger.info("应用关闭")

def create_app() -> FastAPI:
    """创建 FastAPI 应用实例"""
    application = FastAPI(
        title="西安灾害链预测服务",
        description="基于动态贝叶斯网络的暴雨/地震灾害链预测API",
        version="1.0.0",
        lifespan=lifespan,
    )

    @application.middleware("http")
    async def log_requests(request: Request, call_next):
        """请求日志中间件"""
        start = time.time()
        response = await call_next(request)
        elapsed = time.time() - start
        # 静默健康检查探针
        if request.url.path == "/" and request.method == "GET":
            return response
        logger.info(f"{request.method} {request.url.path} -> {response.status_code} ({elapsed:.3f}s)")
        return response

    # 注册路由
    from app.api import register_routers
    register_routers(application)

    return application