该函数接收的参数与*路径操作函数*的参数相同。

/// tip | 提示

下一章会介绍除了函数之外，还有哪些“东西”可以用作依赖项。

///

接收到新的请求时，**FastAPI** 会负责：

* 用正确的参数调用你的依赖项（“dependable”）函数
* 获取函数返回的结果
* 将该结果赋值给你的*路径操作函数*中的参数

```mermaid
graph TB

common_parameters(["common_parameters"])
read_items["/items/"]
read_users["/users/"]

common_parameters --> read_items
common_parameters --> read_users
```

Але FastAPI знатиме, що спочатку треба розв'язати `query_extractor`, щоб передати його результат у `query_or_cookie_extractor` під час виклику.

///

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

Ancak **FastAPI**, `query_or_cookie_extractor`'ı çağırmadan önce `query_extractor`'ı önce çözmesi gerektiğini bilir ve onun sonucunu `query_or_cookie_extractor`'a aktarır.

///

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

Aber **FastAPI** wird wissen, dass es zuerst `query_extractor` auflösen muss, um dessen Resultat an `query_or_cookie_extractor` zu übergeben, wenn dieses aufgerufen wird.

///

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

Pero **FastAPI** sabrá que tiene que resolver `query_extractor` primero, para pasar los resultados de eso a `query_or_cookie_extractor` al llamarlo.

///

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

* Ihre Abhängigkeitsfunktion („Dependable“) mit den richtigen Parametern aufzurufen.
* Sich das Ergebnis von dieser Funktion zu holen.
* Dieses Ergebnis dem Parameter Ihrer *Pfadoperation-Funktion* zuzuweisen.

```mermaid
graph TB

common_parameters(["common_parameters"])
read_items["/items/"]
read_users["/users/"]

common_parameters --> read_items
common_parameters --> read_users
```

	ZRSUBHNB Z22.S, Z10.S, Z8.H                       // 4879b645
	ZRSUBHNT Z22.S, Z10.S, Z8.H                       // 487db645
	ZSABA Z7.D, Z23.D, Z13.D                          // edfac745
	// TODO: SABAL  <Zda>.<T>, <Zn>.<Tb>, <Zm>.<Tb>
	ZSABALB Z8.B, Z4.B, Z30.H                         // 9ec04845
	ZSABALT Z8.B, Z4.B, Z30.H                         // 9ec44845
	ZSABD Z15.B, Z0.B, P3.M, Z0.B                     // e00d0c04

Но **FastAPI** будет знать, что сначала он должен выполнить `query_extractor`, чтобы передать результаты этого в `query_or_cookie_extractor` при его вызове.

///

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

* Chamar sua dependência ("dependable") com os parâmetros corretos.
* Obter o resultado da função.
* Atribuir esse resultado para o parâmetro em sua *função de operação de rota*.

```mermaid
graph TB

common_parameters(["common_parameters"])
read_items["/items/"]
read_users["/users/"]

common_parameters --> read_items
common_parameters --> read_users
```

			}
		}
		if should < 10 {
			t.Errorf("host %q only connects to %d hosts", hosts[x], should)
		}
		t.Logf("host %q should connect to %d hosts", hosts[x], should)
	}
}

func startServer(t testing.TB, listener net.Listener, handler http.Handler) (server *httptest.Server) {
	t.Helper()
	server = httptest.NewUnstartedServer(handler)
	server.Config.Addr = listener.Addr().String()
	server.Listener = listener