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 docs_src.python_types.tutorial007_py39 import process_items


def test_process_items():
    items_t = (1, 2, "foo")
    items_s = {b"a", b"b", b"c"}

app = FastAPI()


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

Yfoo test2/foo fewafewa fewa feawfehahaha hahaafwe hahafawe hahawafe a fwefewa test2/sparse...

Wenn Sie mit dieser *Pfadoperation* kommunizieren und zwei HTTP-Header senden, wie:

```
X-Token: foo
X-Token: bar
```

Dann wäre die <abbr title="Response – Antwort: Daten, die der Server zum anfragenden Client zurücksendet">Response</abbr>:

```JSON
{
    "X-Token values": [
        "bar",
        "foo"
    ]
}
```

## Zusammenfassung { #recap }

例如，声明 `X-Token` 多次出现的请求头，可以写成这样：

{* ../../docs_src/header_params/tutorial003_an_py310.py hl[9] *}

与*路径操作*通信时，以下面的方式发送两个 HTTP 请求头：

```
X-Token: foo
X-Token: bar
```

响应结果是：

```JSON
{
    "X-Token values": [
        "bar",
        "foo"
    ]
}
```

## 小结

使用 `Header` 声明请求头的方式与 `Query`、`Path` 、`Cookie` 相同。

from fastapi import FastAPI

app = FastAPI()

fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]


@app.get("/items/")
async def read_item(skip: int = 0, limit: int = 10):

from fastapi import FastAPI

app = FastAPI()


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

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", operation_id="some_specific_id_you_define")
async def read_items():

          {
            set("foo");
          }
        };
    assertFalse(future.cancel(true));
    assertFalse(future.isCancelled());
    assertTrue(future.isDone());
  }

  public void testGetWithTimeoutDoneFuture() throws Exception {
    AbstractFuture<String> future =
        new AbstractFuture<String>() {
          {
            set("foo");
          }
        };