Code Review: Node.js Memory Leak

hardCode ReviewJS / TS

Problem Statement

Review the following WebSocket stream manager and query cache. Identify why process memory grows continuously over time, locate uncleaned event listeners/timers, and propose a leak-free implementation.

Code under review

JAVASCRIPT• handler.js

Pairlet Snippet

const EventEmitter = require('events');
const globalBus = new EventEmitter();

const queryCache = {};

function handleClientConnection(socket, req) {
  const userId = req.headers['x-user-id'];

  globalBus.on('system_broadcast', (msg) => {
    socket.send(JSON.stringify({ type: 'broadcast', data: msg }));
  });

  socket.on('query', async (queryStr) => {
    if (!queryCache[queryStr]) {
      queryCache[queryStr] = await runHeavyQuery(queryStr);
    }
    socket.send(JSON.stringify(queryCache[queryStr]));
  });

  setInterval(() => {
    socket.send(JSON.stringify({ ping: Date.now() }));
  }, 5000);
}

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Code Review: Node.js Memory Leak

Problem Statement

Code under review

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