broadcast([options])

• options <Object>
  • highWaterMark <number> 缓冲区大小（以槽为单位）。必须 >= 1；小于 1 的值将被限制为 1。默认值： 16。
  • backpressure <string> 'strict'、'block'、'drop-oldest' 或 'drop-newest'。默认值： 'strict'。
  • signal <AbortSignal>
• 返回：<Object>
  • writer BroadcastWriter
  • broadcast Broadcast

创建一个推模式多消费者广播通道。单个写入器将数据推送给多个消费者。每个消费者在共享缓冲区中都有一个独立的游标。

🌐 Create a push-model multi-consumer broadcast channel. A single writer pushes data to multiple consumers. Each consumer has an independent cursor into a shared buffer.

import { broadcast, text } from 'node:stream/iter';

const { writer, broadcast: bc } = broadcast();

// Create consumers before writing
const c1 = bc.push();  // Consumer 1
const c2 = bc.push();  // Consumer 2

// Producer and consumers must run concurrently. Awaited writes
// block when the buffer fills until consumers read.
const producing = (async () => {
  await writer.write('hello');
  await writer.end();
})();

const [r1, r2] = await Promise.all([text(c1), text(c2)]);
console.log(r1); // 'hello'
console.log(r2); // 'hello'
await producing;const { broadcast, text } = require('node:stream/iter');

async function run() {
  const { writer, broadcast: bc } = broadcast();

  // Create consumers before writing
  const c1 = bc.push();  // Consumer 1
  const c2 = bc.push();  // Consumer 2

  // Producer and consumers must run concurrently. Awaited writes
  // block when the buffer fills until consumers read.
  const producing = (async () => {
    await writer.write('hello');
    await writer.end();
  })();

  const [r1, r2] = await Promise.all([text(c1), text(c2)]);
  console.log(r1); // 'hello'
  console.log(r2); // 'hello'
  await producing;
}

run().catch(console.error);拷贝