from fastapi.testclient import TestClient

items = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}
    yield
    # clean up items
    items.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/items/{item_id}")
async def read_items(item_id: str):
    return items[item_id]


def test_read_items():

//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dsync

//go:generate msgp -file $GOFILE

// LockArgs is minimal required values for any dsync compatible lock operation.
type LockArgs struct {
	// Unique ID of lock/unlock request.
	UID string

	// Resources contains single or multiple entries to be locked/unlocked.

8. Note que esta *função de operação de rota* usa `def` regular em vez de `async def`.

    Como sempre, no FastAPI você pode combinar `def` e `async def` conforme necessário.

    Se você precisar de uma atualização sobre quando usar qual, confira a seção _"Com pressa?"_ na documentação sobre [`async` e `await`](../async.md#in-a-hurry){.internal-link target=_blank}.

8. Nota que esta *path operation function* usa `def` regular en lugar de `async def`.

    Como siempre, en FastAPI puedes combinar `def` y `async def` según sea necesario.

    Si necesitas un repaso sobre cuándo usar cuál, revisa la sección _"¿Con prisa?"_ en la documentación sobre [`async` y `await`](../async.md#in-a-hurry){.internal-link target=_blank}.

from fastapi import Header, HTTPException


async def get_token_header(x_token: str = Header()):
    if x_token != "fake-super-secret-token":
        raise HTTPException(status_code=400, detail="X-Token header invalid")


async def get_query_token(token: str):
    if token != "jessica":

)

app = FastAPI()


async def set_up_request_state_dependency():
    request_state = {"user": "deadpond"}
    contextvar_token = legacy_request_state_context_var.set(request_state)
    yield request_state
    legacy_request_state_context_var.reset(contextvar_token)


@app.middleware("http")
async def custom_middleware(

# Without aliases


@app.get("/optional-str")
async def read_optional_str(p: Annotated[Optional[str], Cookie()] = None):
    return {"p": p}


class CookieModelOptionalStr(BaseModel):
    p: Optional[str] = None


@app.get("/model-optional-str")
async def read_model_optional_str(p: Annotated[CookieModelOptionalStr, Cookie()]):
    return {"p": p.p}

```Python
with open("file.txt") as file:
    file.read()
```

Em versões mais recentes do Python, há também um **gerenciador de contexto assíncrono**. Você o usaria com `async with`:

```Python
async with lifespan(app):
    await do_stuff()
```

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package disk

import (
	"os"
	"syscall"
)

// Fdatasync is fsync on freebsd/darwin
func Fdatasync(f *os.File) error {
	return syscall.Fsync(int(f.Fd()))
}

// FadviseDontNeed is a no-op
func FadviseDontNeed(f *os.File) error {
	return nil

app = FastAPI()


async def common_parameters(
    q: Union[str, None] = None, skip: int = 0, limit: int = 100
):
    return {"q": q, "skip": skip, "limit": limit}


@app.get("/items/")
async def read_items(commons: dict = Depends(common_parameters)):
    return {"message": "Hello Items!", "params": commons}


@app.get("/users/")
async def read_users(commons: dict = Depends(common_parameters)):