import pytest
from dirty_equals import IsDict
from fastapi.testclient import TestClient

from ...utils import needs_py39


@pytest.fixture(name="client")
def get_client():
    from docs_src.dependencies.tutorial004_an_py39 import app

    client = TestClient(app)
    return client


@needs_py39
@pytest.mark.parametrize(
    "path,expected_status,expected_response",
    [
        (
            "/items",

from dirty_equals import IsDict
from fastapi.testclient import TestClient

from docs_src.dependencies.tutorial006 import app

client = TestClient(app)


def test_get_no_headers():
    response = client.get("/items/")
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "missing",

/// info

我们将`SessionLocal()`请求的创建和处理放在一个`try`块中。

然后我们在finally块中关闭它。

通过这种方式，我们确保数据库会话在请求后始终关闭。即使在处理请求时出现异常。

但是您不能从退出代码中引发另一个异常（在yield之后）。可以查阅 [Dependencies with yield and HTTPException](https://fastapi.tiangolo.com/zh/tutorial/dependencies/dependencies-with-yield/#dependencies-with-yield-and-httpexception)

///

*然后，当在路径操作函数*中使用依赖项时，我们使用`Session`，直接从 SQLAlchemy 导入的类型声明它。

*这将为我们在路径操作函数*中提供更好的编辑器支持，因为编辑器将知道`db`参数的类型`Session`：

If you want to secure your API, there are several better things you can do, for example:

* Make sure you have well defined Pydantic models for your request bodies and responses.
* Configure any required permissions and roles using dependencies.
* Never store plaintext passwords, only password hashes.
* Implement and use well-known cryptographic tools, like Passlib and JWT tokens, etc.
* Add more granular permission controls with OAuth2 scopes where needed.
* ...etc.

You can also declare the `Response` parameter in dependencies, and set cookies (and headers) in them.

## Return a `Response` directly

You can also create cookies when returning a `Response` directly in your code.

A common choice is Jinja2, the same one used by Flask and other tools.

There are utilities to configure it easily that you can use directly in your **FastAPI** application (provided by Starlette).

## Install dependencies

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and install `jinja2`:

<div class="termy">

```console
$ pip install jinja2

---> 100%

import pytest
from dirty_equals import IsDict
from fastapi.testclient import TestClient

from ...utils import needs_py39


@pytest.fixture(name="client")
def get_client():
    from docs_src.dependencies.tutorial001_an_py39 import app

    client = TestClient(app)
    return client


@needs_py39
@pytest.mark.parametrize(
    "path,expected_status,expected_response",
    [

# -*- coding: utf-8 -*-
import json
# standard.
import os

import certifi
# Dependencies
import urllib3
from botocore.credentials import CredentialProvider, RefreshableCredentials
from botocore.exceptions import CredentialRetrievalError
from dateutil.parser import parse

from .sts_element import STSElement


class ClientGrantsCredentialProvider(CredentialProvider):
    """

### Dépendances

La même chose s'applique aux dépendances. Si une dépendance est définie avec `def` plutôt que `async def`, elle est exécutée dans la threadpool externe.

### Sous-dépendances

* It can do something to that **response** or run any needed code.
* Then it returns the **response**.

/// note | "Technical Details"

If you have dependencies with `yield`, the exit code will run *after* the middleware.

If there were any background tasks (documented later), they will run *after* all the middleware.

///

## Create a middleware