node-js-for-other-things

NodeJS for Other Things

Command-Line

Sample App - Reading CSV Crime Data

First, create an empty directory, and npm init in it

mkdir crimedata
cd crimedata
npm init

{
  "name": "crimedata",
  ...
  "bin": {
      "crimedata": "./index.js"
  }
}

#!/usr/bin/env node

console.log('Hello');

npm install -g
snippet

Reading CSV

http://csv.adaltas.com/

npm install --save csv-parse

Example

var parse = require("csv-parse");
parse(
    fs.readFileSync(inputFile, "utf-8"),
    {
        delimiter: ",",
        ltrim: true,
        rtrim: true,
        columns: true
    },
    function (err, data) { ... });

Showing a table

https://github.com/Automattic/cli-table

npm install --save cli-table

Example:

┌──────────────────────────────┬──────────┬──────────┐
│ District                     │ Count    │ %        │
├──────────────────────────────┼──────────┼──────────┤
│ 1                            │ 868      │ 11       │
├──────────────────────────────┼──────────┼──────────┤
│ 2                            │ 1462     │ 19       │
├──────────────────────────────┼──────────┼──────────┤
│ 3                            │ 1575     │ 21       │
├──────────────────────────────┼──────────┼──────────┤
│ 4                            │ 1161     │ 15       │
├──────────────────────────────┼──────────┼──────────┤
│ 5                            │ 1159     │ 15       │
├──────────────────────────────┼──────────┼──────────┤
│ 6                            │ 1359     │ 18       │
├──────────────────────────────┼──────────┼──────────┤
│ Total                        │ 7584     │ 100      │
└──────────────────────────────┴──────────┴──────────┘

Color

Using chalk!

https://github.com/chalk/chalk

Big Files

https://github.com/Osterjour/line-by-line

npm install line-by-line

var LineByLineReader = require('line-by-line'),
    lr = new LineByLineReader('big_file.txt');

lr.on('error', function (err) {
    // 'err' contains error object
});

lr.on('line', function (line) {
    // 'line' contains the current line without the trailing newline character.
});

lr.on('end', function () {
    // All lines are read, file is closed now.
});

Progress bars

https://github.com/tj/node-progress

Installation:

npm install progress

Example:

var ProgressBar = require('progress');

var bar = new ProgressBar(':bar', { total: 10 });
var timer = setInterval(function () {
  bar.tick();
  if (bar.complete) {
    console.log('\ncomplete\n');
    clearInterval(timer);
  }
}, 100);

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Prompting for Questions

https://github.com/SBoudrias/Inquirer.js

Installation:

npm install inquirer

Usage:

var inquirer = require("inquirer");
inquirer.prompt([/* Pass your questions in here */], function( answers ) {
    // Use user feedback for... whatever!!
});

Program Choices

https://github.com/tj/commander.js/

npm install --save commander

var program = require('commander');

program
    .arguments('<file>')
    .option('-u, --username <username>', 'The user to authenticate as')
    .option('-p, --password <password>', 'The user\'s password')
    .action(function(file) {
        console.log('user: %s pass: %s file: %s',
        program.username, program.password, file);
        })
    .parse(process.argv);

Quick Apps

HTTP server

Author: Marak Squires

a simple zero-configuration command-line http server

https://github.com/indexzero/http-server

Installation:

npm install http-server -g

Usage:

http-server [path] [options]

Robotics

Projects

• http://nodebots.io/ - Robots powered by JavaScript

• https://github.com/rwaldron/johnny-five - JavaScript Robotics and IoT programming framework

  JavaScript Robotics and IoT programming framework

  Arduino (all models), Electric Imp, Beagle Bone, Intel Galileo & Edison, Linino One, Pinoccio, pcDuino3, Raspberry Pi, Particle/Spark Core & Photon, Tessel 2, TI Launchpad and more

• https://cylonjs.com/ - Cylon

Spark (Particle) Photon Example w/ Cylon

http://cylonjs.com/documentation/platforms/particle/

Installation:

npm init
npm install --save cylon
npm install --save cylon cylon-spark

Uses:

http://voodoospark.me/

https://raw.githubusercontent.com/voodootikigod/voodoospark/master/firmware/voodoospark.cpp

Deploy via:

http://build.particle.io

Run this to get your local IP address:

curl "https://api.spark.io/v1/devices/{DEVICE-ID}/endpoint?access_token={ACCESS-TOKEN}"

Result:

{
  "cmd": "VarReturn",
  "name": "endpoint",
  "result": "192.168.1.10:48879",
  "coreInfo": {
    "last_app": "",
    "last_heard": "2014-05-08T02:51:48.826Z",
    "connected": true,
    "deviceID": "{DEVICE-ID}"
  }
}

Desktop Automation

https://github.com/octalmage/robotjs

Example interaction on the Node.js REPL: > require("openurl").open("http://rauschma.de") > require("openurl").open("mailto:john@example.com") Install via npm: npm install openurl