# Événements envoyés par le serveur (SSE) { #server-sent-events-sse }

Vous pouvez diffuser des données vers le client en utilisant les **Server-Sent Events** (SSE).

C'est similaire à [Diffuser des JSON Lines](stream-json-lines.md), mais cela utilise le format `text/event-stream`, pris en charge nativement par les navigateurs via l’API [`EventSource`](https://developer.mozilla.org/en-US/docs/Web/API/EventSource).

/// info | Info

Ajouté dans FastAPI 0.135.0.

    public static final String ROLE_USER = "user";

    /** The role identifier for assistant messages. */
    public static final String ROLE_ASSISTANT = "assistant";

    /** The role of the message sender. */
    private String role;

    /** The content of the message. */
    private String content;

    /**
     * Default constructor.
     */
    public LlmMessage() {
    }

    /**

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      <a title="Deploy & scale any full-stack web app on Render. Focus on building apps, not infra." style="display: block; position: relative;" href="https://docs.render.com/deploy-fastapi?utm_source=deploydoc&utm_medium=referral&utm_campaign=fastapi" target="_blank">
        <span class="sponsor-badge">sponsor</span>
        <img class="sponsor-image" src="/img/sponsors/render-banner.svg" />
      </a>
    </div>
    <div class="item">

    public static final String ROLE_ASSISTANT = "assistant";

    /** The unique identifier for this message. */
    private String id;

    /** The role of the message sender (user or assistant). */
    private String role;

    /** The content of the message. */
    private String content;

    /** The timestamp when the message was created. */
    private LocalDateTime timestamp;

    }

    @Test
    public void test_render_null() {
        assertEquals("", markdownRenderer.render(null));
    }

    @Test
    public void test_render_empty() {
        assertEquals("", markdownRenderer.render(""));
    }

    @Test
    public void test_render_plainText() {
        String result = markdownRenderer.render("Hello World");
        assertTrue(result.contains("Hello World"));

     */
    int DCERPC_LAST_FRAG = 0x02; /* Last fragment */
    /**
     * Pending cancel flag - indicates cancel was pending at sender
     */
    int DCERPC_PENDING_CANCEL = 0x04; /* Cancel was pending at sender */
    /**
     * Reserved flag for future use
     */
    int DCERPC_RESERVED_1 = 0x08;
    /**
     * Supports concurrent multiplexing flag
     */

    /** HTTP/2: The peer must not send a PUSH_PROMISE frame when this is 0. */
    const val ENABLE_PUSH = 2

    /** Sender's maximum number of concurrent streams. */
    const val MAX_CONCURRENT_STREAMS = 3

    /** Window size in bytes. */
    const val INITIAL_WINDOW_SIZE = 4

    /** HTTP/2: Size in bytes of the largest frame payload the sender will accept. */
    const val MAX_FRAME_SIZE = 5

Ви можете транслювати дані клієнту за допомогою **Server-Sent Events** (SSE).

Це подібно до [Потік JSON Lines](stream-json-lines.md), але використовує формат `text/event-stream`, який нативно підтримується браузерами через [API `EventSource`](https://developer.mozilla.org/en-US/docs/Web/API/EventSource).

/// info | Інформація

Додано у FastAPI 0.135.0.

///

# 服务器发送事件（SSE） { #server-sent-events-sse }

你可以使用**服务器发送事件**（SSE）向客户端流式发送数据。

这类似于[流式传输 JSON Lines](stream-json-lines.md)，但使用 `text/event-stream` 格式，浏览器原生通过 [`EventSource` API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource) 支持。

/// info | 信息

新增于 FastAPI 0.135.0。

///

## 什么是服务器发送事件？ { #what-are-server-sent-events }

SSE 是一种通过 HTTP 从服务器向客户端流式传输数据的标准。

每个事件是一个带有 `data`、`event`、`id` 和 `retry` 等“字段”的小文本块，以空行分隔。

      placeholder: Tell us what you see!
      value:
      render: shell
    validations:
      required: true
  - type: textarea
    id: logs
    attributes:
      label: Relevant log output
      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.