====== Node.js ======


===== dirty =====
Key Value Database ([[https://www.npmjs.org/package/dirty|npmjs.org]])
<code javascript>
var dirty = require('dirty');
var db = dirty('/store.db');
var data = db.get('foobar');
db.set('foobar', "some content");
</code>

===== request =====
HTTP Requests ([[https://www.npmjs.org/package/request|npmjs.org]])
<code javascript>
var request = require('request');
request(url, function (error, response, html) {
  if (error || response.statusCode != 200) { console.error(error, response); return false;}
  console.log(html);
});
</code>

===== cheerio =====
jQuery like DOM Parser ([[https://www.npmjs.org/package/cheerio|npmjs.org]])
<code javascript>
var cheerio = require('cheerio');
var $ = cheerio.load(body);
</code>

===== underscore =====
Utiliys ([[https://www.npmjs.org/package/underscore|npmjs.org]])
<code javascript>
var _ = require('underscore');
</code>

===== dialog =====
Window Prompts ([[https://www.npmjs.org/package/dialog|npmjs.org]])
<code javascript>
var dialog = require('dialog');
dialog.info("text", "title");



===== commander =====
Commandline Parameter ([[https://www.npmjs.org/package/commander|npmjs.org]])
<code javascript>
var argv = require('commander');

argv
  .version('0.0.1')
  .option('-p, --peppers', 'Add peppers')
  .option('-c, --cheese [type]', 'Add type of cheese [marble]', 'marble')
  .parse(process.argv);

console.log('you ordered a pizza with:');
if (argv .peppers) console.log('  - peppers');
console.log('  - %s cheese', program.cheese);
</code>


===== prompt =====
Userinput Abfrage ([[https://www.npmjs.org/package/prompt|npmjs.org]])

<code javascript>
var prompt = require('prompt');
prompt.get(['username', 'email'], function (err, result) {
  console.log('Command-line input received:');
  console.log('  username: ' + result.username);
  console.log('  email: ' + result.email);
});
</code>



===== fs-extra =====
Extra FileSystem tools ([[https://www.npmjs.org/package/fs-extra|npmjs.org]])

<code javascript>
var fs = require('fs-extra')
 
// Async with promises:
fs.copy('/tmp/myfile', '/tmp/mynewfile')
  .then(() => console.log('success!'))
  .catch(err => console.error(err))
 
// Async with callbacks:
fs.copy('/tmp/myfile', '/tmp/mynewfile', err => {
  if (err) return console.error(err)
  console.log('success!')
})
 
// Sync:
try {
  fs.copySync('/tmp/myfile', '/tmp/mynewfile')
  console.log('success!')
} catch (err) {
  console.error(err)
}
</code>

===== mime =====
MIME-Type ([[https://www.npmjs.org/package/mime|npmjs.org]])
https://www.npmjs.org/package/mime

<code javascript>
var mime = require('mime');

mime.lookup('/path/to/file.txt');         // => 'text/plain'
mime.lookup('file.txt');                  // => 'text/plain'
mime.lookup('.TXT');                      // => 'text/plain'
mime.lookup('htm');                       // => 'text/html'
</code>


===== async =====
Queue, Warteschlange ([[https://www.npmjs.org/package/async|npmjs.org]])

<code javascript>
var async = require('async');
var queue = async.queue(worker, 40);
queue.push(ip);
queue.drain = function() {
  console.log("all done");
}

function worker (host, callback) {
  console.log("Hard Working");
  for(var i = 0; i <= 5; i++) {
    if(i == 5) 7
      callback();
    }  
  }  
}
</code>


===== socket.io =====
Realtime Web Communication ([[https://www.npmjs.org/package/socket.io|npmjs.org]])

<code javascript server.js>
var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io')(server);
var port = process.env.PORT || 8080;

server.listen(port, function () {
  console.log('Server listening at port %d', port);
});

app.use(express.static(__dirname + '/public'));

io.on('connection', function (socket) {
  socket.on('say', function (data) {
    // send to current request socket client
    socket.emit('message', "this is a test");

    // sending to all clients, include sender
    io.sockets.emit('message', "this is a test");

    // sending to all clients except sender
    socket.broadcast.emit('message', "this is a test");

    // sending to all clients in 'game' room(channel) except sender
    socket.broadcast.to('game').emit('message', 'nice game');

    // sending to all clients in 'game' room(channel), include sender
    io.sockets.in('game').emit('message', 'cool game');

    // sending to individual socketid
    io.sockets.socket(socketid).emit('message', 'for your eyes only');
  });
});
</code>

<code javascript client.html>
<html>
  <head></head>
  <body>
    <script src="/socket.io/socket.io.js"></script>
    <script>
      var socket = io();
      socket.emit('say', 'Hello from: ' + prompt("Your Name?"));
      socket.on('message', function (data) {
        console.log(data);
      });      
    </script>
  </body>
</html>
</code>


===== mkdirp=====
([[https://www.npmjs.org/package/mkdirp|npmjs.org]])

<code javascript>
var mkdirp = require('mkdirp');

mkdirp('./tmp/foo/bar/baz', function (err) {
    if (err) console.error(err)
    else console.log('pow!')
});
</code>

===== validator =====
Eingabe Überprüfung ([[https://www.npmjs.org/package/validator|npmjs.org]])

<code javascript>
var validator = require('validator');
validator.isEmail('foo@bar.com'); //=> true
</code>

===== chalk =====
Farben/Colors in der Console ([[https://www.npmjs.org/package/chalk|npmjs.org]])

<code javascript>
var chalk = require('chalk');

// Combine styled and normal strings 
log(chalk.blue('Hello') + 'World' + chalk.red('!'));
 
// Compose multiple styles using the chainable API 
log(chalk.blue.bgRed.bold('Hello world!'));
 
// Pass in multiple arguments 
log(chalk.blue('Hello', 'World!', 'Foo', 'bar', 'biz', 'baz'));

var error = chalk.bold.red;
var warning = chalk.keyword('orange');
console.log(error('Error!'));
console.log(warning('Warning!'));
</code>