- Fix kubelet NodeLease potential performance issues. Kubelet now will try to update lease using cached one instead of get from API Server every time. ([#81174](https://github.com/kubernetes/kubernetes/pull/81174), [@answer1991](https://github.com/answer1991))

### Kubernetes Node system swap support

            "name": "Foo",
            "description": "A very nice Item",
            "price": 35.4,
            "tax": 3.2,
            "tags": ["foo", "bar", "foo"],
        },
    )
    assert response.status_code == 200, response.text
    assert response.json() == {
        "item_id": 123,
        "item": {
            "name": "Foo",
            "description": "A very nice Item",
            "price": 35.4,

    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",

# Dependencies { #dependencies }

**FastAPI** has a very powerful but intuitive **<abbr title="also known as components, resources, providers, services, injectables">Dependency Injection</abbr>** system.

It is designed to be very simple to use, and to make it very easy for any developer to integrate other components with **FastAPI**.

## What is "Dependency Injection" { #what-is-dependency-injection }

from docs_src.query_params.tutorial005_py39 import app

client = TestClient(app)


def test_foo_needy_very():
    response = client.get("/items/foo?needy=very")
    assert response.status_code == 200
    assert response.json() == {"item_id": "foo", "needy": "very"}


def test_foo_no_needy():
    response = client.get("/items/foo")
    assert response.status_code == 422
    assert response.json() == {
        "detail": [

    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")

    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")

    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")