from fastapi.testclient import TestClient

from docs_src.generate_clients.tutorial003 import app

client = TestClient(app)


def test_post_items():
    response = client.post("/items/", json={"name": "Foo", "price": 5})
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Item received"}


def test_post_users():
    response = client.post(

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


@pytest.fixture(name="client")
def get_client():
    from docs_src.body_multiple_params.tutorial001_an import app

    client = TestClient(app)
    return client


def test_post_body_q_bar_content(client: TestClient):
    response = client.put("/items/5?q=bar", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200

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.request_files.tutorial001_an_py39 import app

    client = TestClient(app)
    return client


@needs_py39
def test_post_form_no_body(client: TestClient):
    response = client.post("/files/")

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

from tests.utils import needs_py39


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

    client = TestClient(app)
    return client


@needs_py39
def test_post_body_form(client: TestClient):
    response = client.post("/login/", data={"username": "Foo", "password": "secret"})

from fastapi import APIRouter, Body

router = APIRouter()


@router.post("/compute")
def compute(a: int = Body(), b: str = Body()):

If you are working with **FastAPI** you don't have to worry about that, because that "first" function will be your *path operation function*, and FastAPI will know how to do the right thing.

But if you want to use `async` / `await` without FastAPI, you can do it as well.

### Write your own async code

# Middleware

Sie können Middleware zu **FastAPI**-Anwendungen hinzufügen.

Eine „Middleware“ ist eine Funktion, die mit jedem **Request** arbeitet, bevor er von einer bestimmten *Pfadoperation* verarbeitet wird. Und auch mit jeder **Response**, bevor sie zurückgegeben wird.

* Sie nimmt jeden **Request** entgegen, der an Ihre Anwendung gesendet wird.
* Sie kann dann etwas mit diesem **Request** tun oder beliebigen Code ausführen.

import importlib

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

from tests.utils import needs_py39, needs_py310, needs_pydanticv1, needs_pydanticv2


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial002", marks=needs_pydanticv2),
        pytest.param("tutorial002_py310", marks=[needs_py310, needs_pydanticv2]),

from dirty_equals import IsDict
from fastapi.testclient import TestClient

from docs_src.request_files.tutorial002 import app

client = TestClient(app)


def test_post_form_no_body():
    response = client.post("/files/")
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "missing",

To do that, we declare a method `__call__`:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[12] *}

In this case, this `__call__` is what **FastAPI** will use to check for additional parameters and sub-dependencies, and this is what will be called to pass a value to the parameter in your *path operation function* later.

## Parameterize the instance