@microsoft/fetch-event-source EventSource相关示例文档

参数说明

参数名	描述
headers	仅支持字符串键值对 { “xx”: “xx”}
onopen	成功链接时回调
onmessage	服务器返回消息回调 返回{ data,event,id,retry } ，data即服务器返回数据
onclose	响应完成回调
onerror	发生任何错误的回调，并会自动在1s后重新尝试目前测试函数体内throw err;会阻断重试
openWhenHidden	页面文档被隐藏时会关闭sse链接并在显示时重连 true 无论隐藏与否都不关闭
fetch	默认 window.fetch

服务器代码示例

const http = require('http');

const server = http.createServer((req, res) => {

  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept');

  if (req.method === 'OPTIONS') {
    res.setHeader('Allow', 'GET, POST, PUT, DELETE, OPTIONS');
    res && res.sendStatus && res.sendStatus(200);
  }
  
  if (req.url === '/sse') {
    res.writeHead(200, {
      'Content-Type': 'text/event-stream',
      'Cache-Control': 'no-cache',
      'Connection': 'keep-alive'
    });

    let count = 0;

    let timer = setInterval(() => {
      count++;
      res.write(`data: ${Date.now()}\n\n`);

      if (count >= 5) {
        clearInterval(timer);
        res.end();
      }
    }, 1000); 
  } else {
    res.writeHead(404);
    res.end();
  }
});

server.listen(3000, () => {
  console.log('Server listening on port 3000...');
});

前端代码示例

<template>
  <div>
  </div>
</template>

<script setup>
import { fetchEventSource } from '@microsoft/fetch-event-source';


const ctrl = new AbortController();
fetchEventSource('http://localhost:3000/sse', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
  	a: 1,
  	b: 2,
  }),
  signal: ctrl.signal,
  openWhenHidden: true,
  async onopen(response) {
    console.log('onopen',response);
  },
  onmessage(msg) {
    console.log('fetchEventSource:', msg);
  },
  onclose() {
    console.log('onclose');
  },
  onerror(err) {
    console.log('onerror', err);
    ctrl.abort();
    throw err;
  }
});

</script>