response = client.put(
        "/items/5",
        json={"description": "A very nice Item"},
    )
    assert response.status_code == 422, response.text
    assert response.json() == {
        "detail": [
            {
                "loc": ["body", "name"],
                "input": {"description": "A very nice Item"},
                "msg": "Field required",
                "type": "missing",

    return client


def test_post_body_example(client: TestClient):
    response = client.put(
        "/items/5",
        json={
            "name": "Foo",
            "description": "A very nice Item",
            "price": 35.4,
            "tax": 3.2,
        },
    )
    assert response.status_code == 200


def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")

Das bedeutet, dass jeder in Python aus einer Umgebungsvariablen gelesene Wert ein `str` ist und jede Konvertierung in einen anderen Typ oder jede Validierung im Code erfolgen muss.

## Pydantic `Settings` { #pydantic-settings }

    client = TestClient(mod.app)
    return client


def test_put_all(client: TestClient):
    response = client.put(
        "/items/123",
        json={
            "name": "Foo",
            "description": "A very nice Item",
            "price": 35.4,
            "tax": 3.2,
            "tags": ["foo", "bar", "foo"],
            "images": [
                {"url": "http://example.com/image.png", "name": "example image"}

# GraphQL { #graphql }

As **FastAPI** is based on the **ASGI** standard, it's very easy to integrate any **GraphQL** library also compatible with ASGI.

You can combine normal FastAPI *path operations* with GraphQL on the same application.

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.

    data = {
        "name": "Special Offer",
        "description": "This is a special offer",
        "price": 38.6,
        "items": [
            {
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,
                "tax": 3.2,
                "tags": ["foo"],
                "images": [
                    {
                        "url": "http://example.com/image.png",