initial_fake_database = {"rick": "Rick Sanchez"}

fake_database = initial_fake_database.copy()

initial_state = {"except": False, "finally": False}

state = initial_state.copy()

app = FastAPI()


async def get_database():
    temp_database = fake_database.copy()
    try:
        yield temp_database
        fake_database.update(temp_database)
    except HTTPException:
        state["except"] = True
        raise

 *
 */

package okhttp3

import java.net.InetAddress
import java.net.UnknownHostException
import java.util.concurrent.CountDownLatch
import okio.IOException

/**
 * An async domain name service that resolves IP addresses for host names.
 *
 * The main implementations will typically be implemented using specific DNS libraries such as
 *  * Android DnsResolver
 *  * OkHttp DnsOverHttps

Es handelt sich schlicht um eine Standard-Funktion, die Parameter empfangen kann.

Es kann sich um eine `async def`- oder normale `def`-Funktion handeln. **FastAPI** weiß, wie damit zu verfahren ist.

In diesem Fall schreibt die Taskfunktion in eine Datei (den Versand einer E-Mail simulierend).

Und da der Schreibvorgang nicht `async` und `await` verwendet, definieren wir die Funktion mit normalem `def`:

```Python hl_lines="6-9"

	CurrentSendCalls int64 // CurrentSendCalls is the number of concurrent async Send calls to all targets
	CurrentQueue     int   // Populated if target has a store.
	TotalEvents      int64
	FailedEvents     int64 // Number of failed events per target
}

// TargetList - holds list of targets indexed by target ID.
type TargetList struct {
	// The number of concurrent async Send calls to all targets
	currentSendCalls  atomic.Int64

```Python hl_lines="1"
async def needy_dependency(fresh_value: Annotated[str, Depends(get_value, use_cache=False)]):
    return {"fresh_value": fresh_value}
```

////

//// tab | Python 3.6+ без Annotated

/// tip | "Подсказка"

Предпочтительнее использовать версию с аннотацией, если это возможно.

///

```Python hl_lines="1"

//// tab | Python 3.8+

```Python hl_lines="1"
async def needy_dependency(fresh_value: Annotated[str, Depends(get_value, use_cache=False)]):
    return {"fresh_value": fresh_value}
```

////

//// tab | Python 3.8+ non-Annotated

/// tip | "Dica"

Utilize a versão com `Annotated` se possível.

///

```Python hl_lines="1"

```

⤴️ 👥 🔜 📣 *➡ 🛠️ 🔢* & 🔗 🍵 `async def`, ⏮️ 😐 `def`,:

```Python hl_lines="2"
@app.get("/users/{user_id}", response_model=schemas.User)
def read_user(user_id: int, db: Session = Depends(get_db)):
    db_user = crud.get_user(db, user_id=user_id)
    ...
```

/// info

🚥 👆 💪 🔗 👆 🔗 💽 🔁, 👀 [🔁 🗄 (🔗) 💽](../advanced/async-sql-databases.md){.internal-link target=_blank}.

///

        model_config = ConfigDict(extra="forbid")
    else:

        class Config:
            extra = "forbid"


class Foo(FooBaseModel):
    pass


app = FastAPI()


@app.post("/")
async def post(
    foo: Union[Foo, None] = None,
):
    return foo


client = TestClient(app)


def test_call_invalid():
    response = client.post("/", json={"foo": {"bar": "baz"}})

    assert testing_file_store
    assert testing_file_store[0].file.closed


# For UploadFile coverage, segments copied from Starlette tests


@pytest.mark.anyio
async def test_upload_file():
    stream = io.BytesIO(b"data")
    file = UploadFile(filename="file", file=stream, size=4)
    assert await file.read() == b"data"
    assert file.size == 4
    await file.write(b" and more data!")

// which creates a remote input, to simulate a scenario that the remote input
// is not ready when we start running an op or a function.
void TestRemoteExecuteSilentCopies(bool async, bool remote, bool func,
                                   bool heavy_load_on_streaming_rpc,
                                   bool remote_func_outputs = false,
                                   bool has_packed_input = false);