from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[str, Query(min_length=3)] = "fixedquery"):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

            " default value together for 'foo'"
        ),
    ):

        @app.get("/")
        async def get3(foo: Annotated[int, Query(min_length=1)] = Depends(dep)):
            pass  # pragma: nocover

    client = TestClient(app)
    response = client.get("/multi-query", params={"foo": "5"})
    assert response.status_code == 200

@app.get("/path/param-minlength/{item_id}")
def get_path_param_min_length(item_id: str = Path(min_length=3)):
    return item_id


@app.get("/path/param-maxlength/{item_id}")
def get_path_param_max_length(item_id: str = Path(max_length=3)):
    return item_id


@app.get("/path/param-min_maxlength/{item_id}")
def get_path_param_min_max_length(item_id: str = Path(max_length=3, min_length=2)):
    return item_id


@app.get("/path/param-gt/{item_id}")

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})

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: str = Query(default="fixedquery", min_length=3)):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[str, Query(min_length=3)]):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from fastapi import FastAPI, Query

app = FastAPI()


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

因為 `Annotated` 可以有多個中繼資料註解，你甚至可以用同一個函式配合其他工具，例如 [Typer](https://typer.tiangolo.com/)。🚀

## 加入更多驗證 { #add-more-validations }

你也可以加入 `min_length` 參數：

{* ../../docs_src/query_params_str_validations/tutorial003_an_py310.py hl[10] *}

## 加入正規表示式 { #add-regular-expressions }

    suppress the check there but enforce it everywhere else. This prevents the list from getting longer even if it is
    unfair. -->
  <module name="LineLength">
    <property name="max" value="140" />
    <property name="ignorePattern" value="^ *\* *https?://[^ ]+$" />
  </module>

  <module name="TreeWalker">

## Больше валидаций { #add-more-validations }

Можно также добавить параметр `min_length`:

{* ../../docs_src/query_params_str_validations/tutorial003_an_py310.py hl[10] *}

## Регулярные выражения { #add-regular-expressions }