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
    finally:
        state["finally"] = True

    try:
        yield dep_a
    finally:
        dep_a.close()


async def dependency_b(dep_a=Depends(dependency_a)):
    dep_b = generate_dep_b()
    try:
        yield dep_b
    finally:
        dep_b.close(dep_a)


async def dependency_c(dep_b=Depends(dependency_b)):
    dep_c = generate_dep_c()
    try:
        yield dep_c
    finally:

        raise
    finally:
        state["/async_raise"] = "asyncgen raise finalized"


def generator_state_try(state: dict[str, str] = Depends(get_state)):
    state["/sync_raise"] = "generator raise started"
    try:
        yield state["/sync_raise"]
    except SyncDependencyError:
        errors.append("/sync_raise")
        raise
    finally:

from fastapi import Depends, FastAPI

app = FastAPI()


def get_username():
    try:
        yield "Rick"
    finally:
        print("Cleanup up before response is sent")


@app.get("/users/me")
def get_user_me(username: str = Depends(get_username, scope="function")):

        private final boolean debugEnabled;
        private final LinkedList<Object> interpolationTargets;
        private final StringSearchModelInterpolator modelInterpolator;
        private final Logger logger;
        private final List<ValueSource> valueSources;
        private final List<InterpolationPostProcessor> postProcessors;

        InterpolateObjectAction(
                Object target,

            else:
                raise ValueError("Session closed")


@contextmanager
def acquire_session() -> Generator[Session, None, None]:
    session = Session()
    try:
        yield session
    finally:
        session.open = False


def dep_session() -> Any:
    with acquire_session() as s:
        yield s


def broken_dep_session() -> Any:
    with acquire_session() as s:
        s.open = False

async def get_db():
    db = DBSession()
    try:
        yield db
    finally:

from typing import Annotated

from fastapi import Depends, FastAPI

app = FastAPI()


def get_username():
    try:
        yield "Rick"
    finally:
        print("Cleanup up before response is sent")


@app.get("/users/me")
def get_user_me(username: Annotated[str, Depends(get_username, scope="function")]):

            else:
                raise ValueError("Session closed")


@contextmanager
def acquire_session() -> Generator[Session, None, None]:
    session = Session()
    try:
        yield session
    finally:
        session.open = False


def dep_session() -> Any:
    with acquire_session() as s:
        yield s


def broken_dep_session() -> Any:
    with acquire_session() as s:
        s.open = False

Таким образом, можно искать конкретное исключение внутри зависимости с помощью `except SomeException`.

Точно так же можно использовать `finally`, чтобы убедиться, что обязательные шаги при выходе выполнены независимо от того, было ли исключение или нет.

{* ../../docs_src/dependencies/tutorial007_py39.py hl[3,5] *}