{* ../../docs_src/path_params/tutorial001.py hl[6:7] *}

La valeur du paramètre `item_id` sera transmise à la fonction dans l'argument `item_id`.

Donc, si vous exécutez cet exemple et allez sur <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>,
vous verrez comme réponse :

```JSON
{"item_id":"foo"}
```

## Paramètres de chemin typés

    )
    return TestClient(mod.app)


@pytest.mark.parametrize(
    "path,expected_response",
    [
        ("/items/42?q=", {"item_id": 42}),
        ("/items/123?q=somequery", {"item_id": 123, "q": "somequery"}),
    ],
)
def test_read_items(client: TestClient, path, expected_response):
    response = client.get(path)
    assert response.status_code == 200, response.text

client = TestClient(app)


def test_get_validation_error():
    response = client.get("/items/foo")
    assert response.status_code == 400, response.text
    assert "Validation errors:" in response.text
    assert "Field: ('path', 'item_id')" in response.text


def test_get_http_error():
    response = client.get("/items/3")
    assert response.status_code == 418, response.text

Der Wert des Pfad-Parameters `item_id` wird Ihrer Funktion als das Argument `item_id` übergeben.

Wenn Sie dieses Beispiel ausführen und auf <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a> gehen, sehen Sie als <abbr title="Response – Antwort: Daten, die der Server zum anfragenden Client zurücksendet">Response</abbr>:

```JSON
{"item_id":"foo"}
```

        },
        "openapi": "3.1.0",
        "paths": {
            "/items/{item_id}": {
                "put": {
                    "operationId": "update_item_items__item_id__put",
                    "parameters": [
                        {
                            "in": "path",
                            "name": "item_id",
                            "required": True,
                            "schema": {

def process_items(items_t: tuple[int, int, str], items_s: set[bytes]):

{* ../../docs_src/path_params/tutorial001.py hl[6:7] *}

Yol parametresi olan `item_id`'nin değeri, fonksiyonunuza `item_id` argümanı olarak aktarılacaktır.

Eğer bu örneği çalıştırıp <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a> sayfasına giderseniz, şöyle bir çıktı ile karşılaşırsınız:

```JSON
{"item_id":"foo"}
```

## Tip İçeren Yol Parametreleri

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: str | None = Query(min_length=3)):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

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": [
            {

from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/")
async def read_items(q: Union[str, None] = None):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})