O `TestClient` faz algumas mágicas para invocar a aplicação FastAPI assíncrona em suas funções `def` normais, utilizando o pytest padrão. Porém a mágica não acontece mais quando nós estamos utilizando dentro de funções assíncronas. Ao executar os nossos testes de forma assíncrona, nós não podemos mais utilizar o `TestClient` dentro das nossas funções de teste.

import importlib
import warnings

import pytest
from dirty_equals import IsInt
from fastapi.testclient import TestClient
from inline_snapshot import snapshot
from sqlalchemy import StaticPool
from sqlmodel import SQLModel, create_engine
from sqlmodel.main import default_registry

from tests.utils import needs_py310


def clear_sqlmodel():
    # Clear the tables in the metadata for the default base model
    SQLModel.metadata.clear()

from fastapi.testclient import TestClient

from .config import Settings
from .main import app, get_settings

client = TestClient(app)


def get_settings_override():
    return Settings(admin_email="******@****.***")


app.dependency_overrides[get_settings] = get_settings_override


def test_app():
    response = client.get("/info")
    data = response.json()
    assert data == {
        "app_name": "Awesome API",

# 测试 WebSockets

测试 WebSockets 也使用 `TestClient`。

为此，要在 `with` 语句中使用 `TestClient` 连接 WebSocket。

{* ../../docs_src/app_testing/tutorial002.py hl[27:31] *}

/// note | 笔记

更多细节详见 <a href="https://www.starlette.dev/testclient/#testing-websocket-sessions" class="external-link" target="_blank">Starlette 官档 - 测试 WebSockets</a>。

from pathlib import Path
from typing import Optional

from fastapi import APIRouter, FastAPI, File, UploadFile
from fastapi.exceptions import HTTPException
from fastapi.testclient import TestClient

app = FastAPI()

router = APIRouter()


class ContentSizeLimitMiddleware:
    """Content size limiting middleware for ASGI applications
    Args:
      app (ASGI application): ASGI application

from pathlib import Path

from fastapi.testclient import TestClient

from docs_src.custom_response import tutorial008_py39
from docs_src.custom_response.tutorial008_py39 import app

client = TestClient(app)


def test_get(tmp_path: Path):
    file_path: Path = tmp_path / "large-video-file.mp4"
    tutorial008_py39.some_file_path = str(file_path)
    test_content = b"Fake video bytes"
    file_path.write_bytes(test_content)

# Testing WebSockets { #testing-websockets }

You can use the same `TestClient` to test WebSockets.

For this, you use the `TestClient` in a `with` statement, connecting to the WebSocket:

{* ../../docs_src/app_testing/tutorial002_py39.py hl[27:31] *}

/// note

For more details, check Starlette's documentation for <a href="https://www.starlette.dev/testclient/#testing-websocket-sessions" class="external-link" target="_blank">testing WebSockets</a>.

from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()

items = {}


@app.on_event("startup")
async def startup_event():
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}


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


def test_read_items():
    with TestClient(app) as client:

import pytest
from fastapi import FastAPI
from fastapi.testclient import TestClient


@pytest.fixture(name="app", scope="module")
def get_app():
    with pytest.warns(DeprecationWarning):
        from docs_src.events.tutorial001_py39 import app
    yield app


def test_events(app: FastAPI):
    with TestClient(app) as client:
        response = client.get("/items/foo")
        assert response.status_code == 200, response.text

from fastapi.testclient import TestClient

app = FastAPI()


async def response_status_setter(response: Response):
    response.status_code = 201


async def parent_dep(result=Depends(response_status_setter)):
    return result


@app.get("/", dependencies=[Depends(parent_dep)])
async def get_main():
    return {"msg": "Hello World"}


client = TestClient(app)