SSEMessage

Kind: Interface

Source: src/helper/streaming/sse.ts

Part of: Helper

SSEMessage defines the fields of a Server-Sent Events message emitted by the streaming helper. It carries event payload data, an event name, a message identifier, and an optional retry delay value; data may be a string or a promise that resolves to a string.

Properties

Diagram

mermaid
graph LR
  SSEMessage --> data["data: string | Promise<string>"]
  SSEMessage --> event["event: string"]
  SSEMessage --> id["id: string"]
  SSEMessage --> retry["retry: number"]
  data --> SSEStream["Server-Sent Events stream"]
  event --> SSEStream
  id --> SSEStream
  retry --> SSEStream

Usage

ts
import type { SSEMessage } from "./helper/streaming/sse";

const message: SSEMessage = {
  data: Promise.resolve(JSON.stringify({ status: "complete" })),
  event: "update",
  id: "message-1",
  retry: 3000,
};

const body = await message.data;

console.log(message.event, message.id, message.retry, body);

AI Coding Instructions

• Set data to a string when the payload is already available, or to Promise<string> when payload creation is asynchronous.
• Serialize object payloads before assigning them to data; the interface accepts only string data.
• Keep event aligned with the event names expected by SSE consumers.
• Use id values that let clients identify or resume from a streamed message.
• Treat retry as the client reconnection delay value for the SSE message.

Relationships

• IMPORTS → HtmlEscapedCallbackPhase
• IMPORTS → resolveCallback
• IMPORTS → StreamingApi
• IMPORTS → isOldBunVersion