medium5-10 min34% solve rate

The Memory Leak That Passed Code Review

This Node.js stream implementation looks fine but will crash your server under load.

Node.jsMemoryPerformance

The Code

This code passed code review and works in development. But it has a bug that will cause problems in production.

server.js

1const http = require('http');
2const fs = require('fs');
3 
4const server = http.createServer((req, res) => {
5  const filePath = './large-file.pdf';
6 
7  // Stream the file to the response
8  const stream = fs.createReadStream(filePath);
9  stream.pipe(res);
10 
11  // Log when complete
12  stream.on('end', () => {
13    console.log('File sent successfully');
14  });
15});
16 
17server.listen(3000, () => {
18  console.log('Server running on port 3000');
19});
20 
21// This code passed code review.
22// It will crash your server under load.
23// Can you spot why?

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