The main tasks that you can do right now are:

* [Help others with questions in GitHub](#help-others-with-questions-in-github){.internal-link target=_blank} (see the section above).
* [Review Pull Requests](#review-pull-requests){.internal-link target=_blank} (see the section above).

Those two tasks are what **consume time the most**. That's the main work of maintaining FastAPI.

}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: Union[str, None] = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item_id not in fake_db:

Sebastián Ramírez <******@****.***> 1679142599 +0100

}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: str | None = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item_id not in fake_db:

Beau Barker <******@****.***> 1589710454 +1000

Sebastián Ramírez <******@****.***> 1698179166 +0400

FastAPI will now:

* **Validate** the data making sure that the max length is 50 characters
* Show a **clear error** for the client when the data is not valid
* **Document** the parameter in the OpenAPI schema *path operation* (so it will show up in the **automatic docs UI**)

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


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

    client = TestClient(app)
    return client


def test_users_token_jessica(client: TestClient):
    response = client.get("/users?token=jessica")
    assert response.status_code == 200

from fastapi.testclient import TestClient

from .main import app

client = TestClient(app)


def test_read_item():
    response = client.get("/items/foo", headers={"X-Token": "coneofsilence"})
    assert response.status_code == 200
    assert response.json() == {
        "id": "foo",
        "title": "Foo",
        "description": "There goes my hero",
    }


def test_read_item_bad_token():

from fastapi.testclient import TestClient

from .main import app

client = TestClient(app)


def test_read_item():
    response = client.get("/items/foo", headers={"X-Token": "coneofsilence"})
    assert response.status_code == 200
    assert response.json() == {
        "id": "foo",
        "title": "Foo",
        "description": "There goes my hero",
    }


def test_read_item_bad_token():