async with engine.begin() as conn: await conn.run_sync(metadata.create_all) # 依赖以获取异步数据库会话 async def get_async_db(): async with AsyncSessionLocal() as session: yield session # 启动:初始化数据库 async def initialize_database(): await init_db() 在这个版本中,请求是异步处理的...
asyncwithengine.begin()asconn: await conn.run_sync(metadata.create_all)# 获取异步数据库会话的依赖async def get_async_db(): asyncwithAsyncSessionLocal()assession: yieldsession# 启动:初始化数据库async def initialize_database(): await init_db() 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. ...
classItem(BaseModel):name:strdescription:str@app.post("/items/")asyncdefcreate_item(item:Item):...
allow_headers=["*"], ) @app.get("/") async def main(): return {"message": "Hell...
@api.get('/handler') async def handler(): ... # Slow async function await my_async_function() ... # Slow running sync function sync_function() As written above, it'll work, but the sync function will block the async event loop. Is there any way to avoid this? If the handler is...
@app.get('/sync1',dependencies=[Depends(auth)])asyncdefsync1():return{'hello':sync_task()} But we can do nothing about the code below, this is completely up to Python interpreter. withThreadPoolExecutor()astp:return{'hello':tp.submit(sync_task).result()} ...
About def vs async def 关于def 与 sync def Here we are using SQLAlchemy code inside of the path operation function and in the dependency, and, in turn, it will go and communicate with an external database. 在这里,我们在路径操作函数内部和依赖项中使用 SQLAlchemy 代码,然后它将与外部数据...
FastAPI 在 线程池 中运行 sync 路由,阻塞式 I/O 操作不会阻止 事件循环 执行任务。 否则,如果路由定义为 async,则会通过 await 常规调用,FastAPI 信任你仅执行非阻塞 I/O 操作。如果你违背了这种信任,在异步路由中执行阻塞操作,事件循环将无法运行下一个任务,直到阻塞操作完成。
import azure.functions as func import fastapi app = fastapi.FastAPI() @app.get("/sample") async def index(): return { "info": "Try /hello/Shivani for parameterized route.", } @app.get("/hello/{name}") async def get_name(name: str): return { "name": name, } Running...
app.add_middleware(sync_middleware) # 外层同步中间件 app.add_middleware(async_middleware) # 内层异步中间件 潜在问题:外层的同步中间件若包含阻塞操作,会降低内层异步中间件的性能优势。 最佳实践:尽量统一中间件类型(全同步或全异步),或确保外层中间件无阻塞。