Trace requires

[targos]

PoC using a preload script:

// logrequires.js
'use strict';

var js = require.extensions['.js'];

require.extensions['.js'] = (...args) => {
  console.log('loading module', args[0].filename);
  return js(...args);
};

node -r ./logrequires.js myscript.js

[targos]

basic implementation done: ndbg trace-requires myscript.js to test.

[fraxken]

It could be interesting to hook the performance of each module at the same time no ? (With perf_hooks).

const {
    performance,
    PerformanceObserver
} = require("perf_hooks");
const mod = require("module");

// Monkey patch the require function
mod.Module.prototype.require =
    performance.timerify(mod.Module.prototype.require);
require = performance.timerify(require);

// Activate the observer
const obs = new PerformanceObserver((list) => {
    let fullRequireTime = 0;
    const entries = list.getEntries();
    entries.forEach((entry) => {
        console.log(`module '${entry[0]}' load in %s ms`, entry.duration);
        fullRequireTime += entry.duration;
    });
    console.log(`Average require time: ${fullRequireTime / entries.length} ms`);
    console.log(`Complete load time ${fullRequireTime} ms`);
    obs.disconnect();
});
obs.observe({ entryTypes: ["function"], buffered: true });