from typing import Annotated, Union

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[Union[str, None], Query(min_length=3, max_length=50)] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from unittest.mock import patch

from docs_src.python_types.tutorial008_py39 import process_items


def test_process_items():
    with patch("builtins.print") as mock_print:
        process_items({"a": 1.0, "b": 2.5})

    assert mock_print.call_count == 4
    call_args = [arg.args for arg in mock_print.call_args_list]
    assert call_args == [
        ("a",),
        (1.0,),
        ("b",),
        (2.5,),

    }

    /**
     * Removes a stored crawling configuration from the session-based storage.
     *
     * @param sessionCountId the session count ID of the configuration to remove
     */
    public void remove(final String sessionCountId) {
        crawlingConfigMap.remove(sessionCountId);
    }

    /**
     * Retrieves a stored crawling configuration from the session-based storage.
     *

        transformValues(
            underlying,
            new Function<@Nullable String, Boolean>() {
              @Override
              public Boolean apply(@Nullable String from) {
                return from == null;
              }
            });
    Map<String, Boolean> expected = ImmutableMap.of("a", true, "b", false);
    assertMapsEqual(expected, map);
    assertEquals(expected.get("a"), map.get("a"));

The docs will show it like this:

<img src="/img/tutorial/query-params-str-validations/image01.png">

## Exclude parameters from OpenAPI { #exclude-parameters-from-openapi }

To exclude a query parameter from the generated OpenAPI schema (and thus, from the automatic documentation systems), set the parameter `include_in_schema` of `Query` to `False`:

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    item_id: int,
    item: Item = Body(
        examples=[
            {
                "name": "Foo",
                "description": "A very nice Item",

from fastapi import FastAPI
from pydantic import BaseModel, HttpUrl

app = FastAPI()


class Image(BaseModel):
    url: HttpUrl
    name: str


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()
    image: Image | None = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):

from typing import Annotated, Union

from fastapi import Depends, FastAPI

app = FastAPI()


async def common_parameters(
    q: Union[str, None] = None, skip: int = 0, limit: int = 100
):
    return {"q": q, "skip": skip, "limit": limit}


CommonsDep = Annotated[dict, Depends(common_parameters)]


@app.get("/items/")
async def read_items(commons: CommonsDep):
    return commons


@app.get("/users/")

from typing import Union

from fastapi import Depends, FastAPI

app = FastAPI()


async def common_parameters(
    q: Union[str, None] = None, skip: int = 0, limit: int = 100
):
    return {"q": q, "skip": skip, "limit": limit}


@app.get("/items/")
async def read_items(commons: dict = Depends(common_parameters)):
    return commons


@app.get("/users/")
async def read_users(commons: dict = Depends(common_parameters)):

from typing import Annotated, Union

from fastapi import Cookie, Depends, FastAPI

app = FastAPI()


def query_extractor(q: Union[str, None] = None):
    return q


def query_or_cookie_extractor(
    q: Annotated[str, Depends(query_extractor)],
    last_query: Annotated[Union[str, None], Cookie()] = None,
):
    if not q:
        return last_query
    return q


@app.get("/items/")
async def read_query(