from fastapi.testclient import TestClient

from docs_src.sub_applications.tutorial001_py39 import app

client = TestClient(app)

openapi_schema_main = {
    "openapi": "3.1.0",
    "info": {"title": "FastAPI", "version": "0.1.0"},
    "paths": {
        "/app": {
            "get": {
                "responses": {
                    "200": {
                        "description": "Successful Response",

import pytest
from fastapi import (
    APIRouter,
    Depends,
    FastAPI,
    Header,
    WebSocket,
    WebSocketDisconnect,
    status,
)
from fastapi.middleware import Middleware
from fastapi.testclient import TestClient

router = APIRouter()
prefix_router = APIRouter()
native_prefix_route = APIRouter(prefix="/native")
app = FastAPI()


@app.websocket_route("/")
async def index(websocket: WebSocket):

<a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a> がベースなので、非常に使いやすく直感的です。

これを使用すると、**FastAPI** と共に <a href="https://docs.pytest.org/" class="external-link" target="_blank">pytest</a> を直接利用できます。

## `TestClient` を使用

`TestClient` をインポートします。

`TestClient` を作成し、**FastAPI** に渡します。

import pytest
from fastapi.testclient import TestClient


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial006_py39"),
        pytest.param("tutorial006_an_py39"),
    ],
)
def get_client(request: pytest.FixtureRequest) -> TestClient:
    mod = importlib.import_module(
        f"docs_src.path_params_numeric_validations.{request.param}"
    )
    return TestClient(mod.app)

from dirty_equals import IsPartialDict
from fastapi import Cookie, FastAPI, Header, Query
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

app = FastAPI()


class Model(BaseModel):
    param: str = Field(alias="param_alias")


@app.get("/query")
async def query_model(data: Model = Query()):
    return {"param": data.param}


@app.get("/header")
async def header_model(data: Model = Header()):

from collections.abc import Awaitable
from contextvars import ContextVar
from typing import Any, Callable, Optional

from fastapi import Depends, FastAPI, Request, Response
from fastapi.testclient import TestClient

legacy_request_state_context_var: ContextVar[Optional[dict[str, Any]]] = ContextVar(
    "legacy_request_state_context_var", default=None
)

app = FastAPI()


async def set_up_request_state_dependency():

from typing import Union

from fastapi import Body, FastAPI, Query
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/query")
def read_query(q: Union[str, None]):
    return q


@app.get("/explicit-query")
def read_explicit_query(q: Union[str, None] = Query()):
    return q


@app.post("/body-embed")
def send_body_embed(b: Union[str, None] = Body(embed=True)):
    return b

from typing import Annotated, Optional

import pytest
from fastapi import FastAPI, File, UploadFile
from fastapi.testclient import TestClient

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-bytes", operation_id="optional_bytes")
async def read_optional_bytes(p: Annotated[Optional[bytes], File()] = None):

from typing import Annotated, Optional

import pytest
from fastapi import FastAPI, Form
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-str", operation_id="optional_str")

from typing import Annotated, Optional

import pytest
from fastapi import FastAPI, Query
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

app = FastAPI()

# =====================================================================================
# Without aliases


@app.get("/optional-list-str")
async def read_optional_list_str(
    p: Annotated[Optional[list[str]], Query()] = None,
):