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// Copyright (c) 2017-2024 Cloudflare, Inc.
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// Licensed under the Apache 2.0 license found in the LICENSE file or at:
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//     https://opensource.org/licenses/Apache-2.0
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// This is a simple SSE server written for Node.js ... it sends a message every second
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// for 10 seconds, then disconnects. The worker.js file will use the EventSource API to
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// connect to this server.
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const { createServer } = require('http');
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let counter = 0;
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function getMessage(txt) {
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  return `data: ${txt}\nid: ${counter++}\n\n`;
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}
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const server = createServer((req, res) => {
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  res.writeHead(200, {
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    'Content-Type': 'text/event-stream',
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    'Cache-Control': 'no-cache',
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    'Connection': 'keep-alive'
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  });
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  res.write(getMessage('Hello World'));
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  let t = setInterval(() => {
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    res.write(getMessage('Hello World'));
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    if (counter === 10) {
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      clearInterval(t);
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      res.end();
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      counter = 0;
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    }
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  }, 1000);
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});
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server.listen(8888, () => {
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  console.log('Server is running...');
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});