Assim, ela envia o primeiro item, o cliente o recebe e começa a processá-lo, enquanto você ainda pode estar produzindo o próximo item.

```mermaid
sequenceDiagram
    participant App
    participant Client

    App->>App: Produce Item 1
    App->>Client: Send Item 1
    App->>App: Produce Item 2
    Client->>Client: Process Item 1
    App->>Client: Send Item 2
    App->>App: Produce Item 3

def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

könnte Ihr Programm so ausgeführt werden:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Funktion ausführen

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: führe Code der Funktion aus

@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

programınız şu şekilde çalışabilir:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code

@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

프로그램은 다음과 같이 실행될 수 있습니다:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code

```Python
@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

你的程式可能會這樣執行：

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code

///

## 什麼是串流？ { #what-is-a-stream }

「**Streaming**」資料表示你的應用會在整個資料序列尚未完全準備好之前，就開始將資料項目傳送給用戶端。

也就是說，它會先送出第一個項目，用戶端接收並開始處理時，你的應用可能仍在產生下一個項目。

```mermaid
sequenceDiagram
    participant App
    participant Client

    App->>App: Produce Item 1
    App->>Client: Send Item 1
    App->>App: Produce Item 2
    Client->>Client: Process Item 1
    App->>Client: Send Item 2
    App->>App: Produce Item 3

@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

ваша програма може виконуватись так:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code

**Proxy**'nin, client ile **application server** arasında forwarded header'ları nasıl eklediğini gösteren görsel bir temsil:

```mermaid
sequenceDiagram
    participant Client
    participant Proxy as Proxy/Load Balancer
    participant Server as FastAPI Server

    Client->>Proxy: HTTPS Request<br/>Host: mysuperapp.com<br/>Path: /items

    Note over Proxy: Proxy adds forwarded headers

@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

seu programa poderia executar assim:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code

def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

your program could execute like this:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code