html不需要库直接F12看
tornado:
1.注意同步异步，其他接口不要卡死 tornado.gen.sleep(1)
2.跨域Access-Control要注意 我之前忘了那三个语句卡住了
还是不熟悉基础知识，要多补习
tornado:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
# @Author : d7L
# @Date : 2024/10/21 10:46
# @File : sse_tornado.py
# @Description:
"""
import tornado.ioloop
import tornado.web
import datetime
class SSEHandler(tornado.web.RequestHandler):
def initialize(self):
self.set_header('Content-Type', 'text/event-stream')
self.set_header('Cache-Control', 'no-cache')
self.set_header('Connection', 'keep-alive')
self.set_header('Access-Control-Allow-Origin', "*")
self.set_header('Access-Control-Allow-Headers', "Content-Type")
self.set_header('Access-Control-Allow-Methods', "GET, POST, OPTIONS")
async def get(self):
try:
while True:
data = f'data: Current time is {datetime.datetime.now().strftime("%H:%M:%S")}\n\n'
self.write(data)
await self.flush()
await tornado.gen.sleep(1)
except tornado.iostream.StreamClosedError:
pass
def make_app():
return tornado.web.Application([
(r"/events", SSEHandler),
])
if __name__ == "__main__":
print("go...")
app = make_app()
app.listen(8888)
tornado.ioloop.IOLoop.current().start()
html::
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<script>
// 创建 EventSource 对象
const eventSource = new EventSource('http://127.0.0.1:8000/events');
// 处理接收到的消息
eventSource.onmessage = function (event) {
console.log(event.data);
document.getElementById('result').innerHTML = event.data;
};
// 处理错误
eventSource.onerror = function (error) {
console.error('SSE Error:', error);
};
</script>
<div id="result"></div>
</body>
</html>
js(没有tornado才用，测后端不需要，前端自己调的):
const express = require('express');
const cors = require('cors');
const app = express();
app.use(cors({
origin: '*',
methods: ['GET', 'POST', 'OPTIONS'],
allowedHeaders: ['Content-Type']
}));
app.get('/events', (req, res) => {
res.writeHead(200, {
'Content-Type': 'text/event-stream',
'Cache-Control': 'no-cache',
'Connection': 'keep-alive'
});
const intervalId = setInterval(() => {
const data = `data: Current time is ${new Date().toLocaleTimeString()}\n\n`;
res.write(data);
}, 1000);
req.on('close', () => {
clearInterval(intervalId);
});
});
const port = 3000;
app.listen(port, () => {
console.log(`Server running at port ${port}`);
});