is a middleware of monitoring Express router, it helps to observe information of R , and . express-watcher esponse Time RAM, heap memory CPU During the time of developing Isomorphic Application(React-Redux-ServerRendering), tracking the issue of performance become harder and harder, because performance could be affected by many factors : — Express server performance — API — Component Design(React) — Algorithm — Browser performance It is a tool that helps me find out performance issue during development stage( ). NOT PRODUCTION!!! Install $ npm install --save express-watcher Usage To print every request var resourceMonitorMiddleware = require('express-watcher').resourceMonitorMiddleware // example without callback function app.use(resourceMonitorMiddleware) To get monitoring data from every request var resourceMonitorMiddlewareCB = require('express-watcher').resourceMonitorMiddlewareCB // example with callback function app.use(function(req, res, next){ ) resourceMonitorMiddlewareCB(req, res, next, function(diffJson){console.log(' diffJson : ', diffJson)})} 1- Monitoring each response Return object as a callback: { diffRss: 0.0078125, diffHeapTotal: 0, diffHeapUsed: 0.012725830078125, diffExternal: 0, diffCpu: 0.000427 } And auto print: 2- Monitoring all time high information All time high information is printed when closing (CRT+c) the node process And auto print: Reference https://www.npmjs.com/package/js-meter https://www.npmjs.com/package/express-watcher
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