Monody - a simple sensors manager

Features

Monody has 2 simple features:

provide some basic sensors to get informations like the CPU usage, memory usage, disk usage
allow for regular interrogation of those sensors

Stability

This package is in a prototyping stage and sensors support only Ubuntu hosts. Contact me for other platforms. I DO NOT recommend using this in production for now since there might be some breaking changes.

Installation

Install using npm:

npm install monody

Create a server.js file:

// file server.js
const monody = require('monody');
const sensors = require('monody/sensors');

// standalone usage of a sensor
sensors.cpu((cpu) => {
  console.log("current cpu usage", cpu);
});

// template for custom sensors
function customSensorTime(cb) {
  const responseData = {
    status: true,
    data: {
      time: new Date()
    },
    msg: "",
    extra: null
  }
  
  cb(responseData, "time");
}

// options for a http sensor
var options = {
  method: 'GET',
  host: 'nodejs.org',
  path: '/en/',
  port: 443
}

// general callback function to display data from the sensors
function callback(data, sensorName) {
  console.log(sensorName, data);
}

// tested with Ubuntu only 
// be carefull and give your sensors enough time to execute
monody.addTask(customSensorTime, callback, 1000);
monody.addTask(sensors.cpu, callback, 5000);
monody.addTask(sensors.mem, callback, 5000);
monody.addTask([sensors.http, options], callback, 5000);

// examples to get disk info and file size
// monody.addTask([sensors.disk, '/dev/sda'], callback, 5000);
// monody.addTask([sensors.fileInfo, 'your_file_name_here'], callback, 5000);

monody.start();

Launch with node server.js.

Anatomy of a sensor

monody sensors is a function that accepts two parameters:

a callback function
an options object

The reponse sent back by the callback function returns 2 parameters:

a response object:
- a status (boolean or string)
- a data object (object)
- a message (string) generally used for informations about errors.
- an extra parameter which can be of any type
a tag name (string) used by the scheduler to identify the sensor

Let's see an example that can be used as a template for your own custom sensors.

function sensorTime(cb) {
  const responseData = {
    status: true,
    data: {
      time: new Date()
    },
    msg: "",
    extra: null
  }
  
  cb(responseData, "time");
}

Available sensors

The package offers the following sensors:

cpu: cpu usage (float)
mem: mem usage (object)
disk: disk usage (float)
fileInfo: file informations(object)
(NEW) http: executes a http call (using node http.request) and returns the native response object

Roadmap

improve documentation
add more sensors
error handling
more examples

Contribute

The interest of this package will grow with the number of sensors. If you are interested in publishing new sensors, contact me: paul.brie@gmail.com.

Changelog

0.0.17 / 2016-09-01: documentation update
0.0.16 / 2016-09-01: bug corrections
0.0.15 / 2016-09-01: minor corrections
0.0.14 / 2016-09-01: new http sensor, all sensors return a standard response object
0.0.13 / 2016-08-29: documentation improvements

mihaisampaleanu/monody