Easy-Monitor

Introduction

A lightweight Node.js performance monitoring tool, you just need to require it at the entrance of your project, then Easy-Monitor will show you your Node.js process details.

I.Functions

Find 5 or more functions that take the longest execution time
Find functions that perform more than expected
Find the functions which V8 engine can not optimize

The number of listings disaplayed above can be configured directly in URL. You can also set your own rule that you can fiter functions and filePaths so that the results is what you really want.

The purpose of Easy-Monitor is to help you more in-depth understanding of our Node process, performance optimization can be more targeted, and ultimately enhance our project experience.

II.Feature

LightWeight：Easy-Monitor is unconventional C/S physical separation model, all you need to to is require in your project, there is no additional server/agent deployment costs.
RunTime：Easy-Monitor can provide you runtime performance and memory details, and it can be used for production.
Stateless：Easy-Monitor always show you your node process status when you visit it.

Compatibility

Node v6.x
Node v5.x
Node v4.x

Temporary don't support Node v7.x.

Quick Start

Easy-Monitor is simple, only three steps you can start your own performance monitor.

I.Install

Simply run as：

npm install easy-monitor

II.Require

Require in your project, argument is your project name, such as:

const easyMonitor = require('easy-monitor');
easyMonitor('your project name');

III.Visit

Open browser, input as below, then you will see detail:

http://127.0.0.1:12333

IV.A thorough example with Express

'use strict';
const easyMonitor = require('easy-monitor');
easyMonitor('your project name');
const express = require('express');
const app = express();

app.get('/hello', function (req, res, next) {
    res.send('hello');
});

app.listen(8082);

Save the above as a JS file, then open your browser and visit http://127.0.0.1:12333, just so simple!

Customization

I.Customization Parameters

Easy-Monitor also remain some important attributes so that we can customize conveniently, it's dependence on the object you set when executing require('easy-monitor')(object), this object can have below attributes as:

logLevel：Number, default is 2, it used to set log level：
- 0：don't output any log
- 1：output error log
- 2：output info log
- 3：output debug log
appName：String, default is getting from process.title, it used to set your project name.
httpServerPort：Numver, default is 12333, it used to set monitor http server port.
filterFunction：function, default filtering out the profiling results of the 'node_modules' and 'anonymous', and all file paths that don't have the string '/', because of these may be system functions. Developer can write function to filter your own results, below is the params and returned value:
- filePath: String, file path that functions at
- funcName: String, function name
- returned value: if true remain, if false filtering out
monitorAuth：function, default don't authentication, it used for authentication, developer can write function for own authentication, below is the params and returned value:
- user：String, it's username
- pass：String, it's password
- returned value：a Promise instance, resolve(true) mean authentication pass, resolve(false) or reject mean authentication failed.

II.Customization Example

Below is a thorough example that Easy-Monitor with Express：

'use strict';
const easyConfig = {
    logLevel: 3, 
    appName: 'My Project 1', 
    httpServerPort: 8888, 
    filterFunction: function (filePath, funcName) {
        if (funcName === 'anonymous' || ~filePath.indexOf('node_modules')) {
            return false;
        }
        return Boolean(/^\(\/.*/.test(filePath));
    }, 
    monitorAuth: function (user, pass) {
        return new Promise(resolve => resolve(Boolean(user === 'admin' && pass === 'lifeishard')));
    }
};
const easyMonitor = require('easy-monitor');
easyMonitor(easyConfig);

const express = require('express');
const app = express();

app.get('/hello', function helloIndex(req, res, next) {
    let date = Date.now();
    while (Date.now() - date < 300) {
    }
    res.send('hello');
});

app.listen(8082);

In this example, log level setted to be 3, monitor http server port changed to be 8888, we also set our own filtering rule and simply authentication rule.

More, /hello setted being blocking after 300ms, you can open http://127.0.0.1:8888 to visit Easy-Monitor home page, to click the project name or pid, then it will do cpu profiling, meanwhile you can visit http://127.0.0.1:8082/hello ceaselessly.

After all, you'll get result by trying it.

Monitor Page Preview

I.HomePage

1.Profiling The Whole Project

As the picture, you can click the project name, this will profiling the whole project's process, include:

single process mode: only main process
cluster mode: all cluster process

2.Profiling The Unique Process

As the picture, there will be multiple child process in cluster mode, you can click unique pid, this will profiling the unique process only.

3.Multi Project Deployment

As the picture, Easy-Monitor support multi project deployment, the usage is exactly the same as the single project, you can refer to Quick Start.

When you deploy multi projects, monitor homepage will display these different project and their child process pid.

II.DetaiPage

1.List of the Time-Executing out of Expected Functions

As the picture, we can add querystring params to customize the expected time and the number of items to display, such as:

?timeout=your expected execution time(ms)
?long_limit=the number of items you want to display
?timeout=your expected execution time(ms)&long_limit=the number of items you want to display

2.List of the Most Time-Consuming Functions

As the picture, we can add querystring params to customize the number of items to display, such as:

?top_limit=the number of items you want to display

3.List of the De-Optimizing Functions By V8 Engine