memory-watch/examples/test-user-tracking.js

Advanced Node.js memory monitoring with stack trace analysis, user code detection, and memory leak identification

const { MemoryWatch } = require("../dist/index");

// Simple test to verify user code tracking
const watch = new MemoryWatch({
  threshold: 0.3, // Low threshold for immediate trigger
  interval: 1000, // Check every second
  actions: [
    (data) => {
      console.log("\n🚨 MEMORY ALERT 🚨");
      console.log(`Memory Usage: ${(data.percentage * 100).toFixed(1)}%`);
      console.log(`Used: ${Math.round(data.usedBytes / 1024 / 1024)}MB`);

      console.log("\n📍 STACK TRACE:");
      if (data.context?.stackTrace && data.context.stackTrace.length > 0) {
        data.context.stackTrace.forEach((trace, index) => {
          const prefix =
            trace.fileName && trace.fileName.includes("test-user-tracking")
              ? "⭐"
              : "  ";
          console.log(`${prefix} ${index + 1}. ${trace.functionName}`);
          if (trace.fileName) {
            console.log(`     → ${trace.fileName}:${trace.lineNumber}`);
          }
        });
      } else {
        console.log("   No stack trace available");
      }

      console.log("\n" + "=".repeat(50));
    },
  ],
});

// Test functions that will show up in stack trace
function memoryHeavyFunction() {
  console.log("🔧 Running memoryHeavyFunction...");

  // Manually capture context
  watch.captureContext("memoryHeavyFunction", __filename, 35);

  // Create memory usage
  const largeArray = [];
  for (let i = 0; i < 50000; i++) {
    largeArray.push({
      id: i,
      data: new Array(100).fill(`item-${i}`),
      metadata: {
        timestamp: new Date(),
        extra: new Array(50).fill(`meta-${i}`),
      },
    });
  }

  console.log(`✅ Created ${largeArray.length} items`);
  return largeArray;
}

function apiSimulation() {
  console.log("🌐 API simulation starting...");

  // Capture this function context
  watch.captureContext("apiSimulation", __filename, 56);

  // Call the memory heavy function
  const result = memoryHeavyFunction();

  // Do some more processing
  const processed = result.map((item) => ({
    ...item,
    processed: true,
    extraData: new Array(20).fill(`processed-${item.id}`),
  }));

  console.log("✅ API simulation completed");
  return processed;
}

console.log("🚀 Testing User Code Tracking...");
console.log("Features:");
console.log("- Manual context capture with captureContext()");
console.log("- Improved stack trace detection");
console.log("- User code highlighting\n");

watch.start();

// Test sequence
setTimeout(() => {
  console.log("Starting memory-intensive operations...");
  apiSimulation();
}, 2000);

// Stop after 10 seconds
setTimeout(() => {
  watch.stop();
  console.log("\n✅ Test completed - Memory tracking stopped");
  process.exit(0);
}, 10000);