Node.js for beginners: description, guide, features

Node.js — JavaScript, JS V8 Chrome. Node.js , -, . Node.js . Node.js. , .

Node.js :

Node.js — JavaScript . Node , . , , push-.

Node.js HTTP- . Node.js . , , , , , . Node , .

Node.JS , , . , .

Node.js — JavaScript

Node JavaScript, JS. Node.js , . JavaScript — Netscape. Microsoft Visual Basic, Sun Tcl, Perl UNIX REXX IBM. JavaScript , , C C ++. , , .

JavaScript - , -. , .

JavaScript , Java ( - , C ++).

JS

JavaScript -. Netscape -. JavaScript Java, C ECMAScript — , Sun Microsystems.

JavaScript — . , - , -. - . , JavaScript - , , . , - .

, PHP ASP, JavaScript HTML- . HTML , JavaScript -. .JS, .

JavaScript, . 7 11. HTML -, «18» .

<script>

function sum(a,b)

{

return a + b;

}

var total = sum(7,11);

alert(total);

</script>

JavaScript <script>, . onClick, onMouseDown, onMouseUp, onKeyDown, onKeyUp, onFocus, onBlur, onSubmit . JavaScript , - JavaScript, jQuery, - .

Node.js, , , / (I/O). Node.js , , . . Node.js , - , .

JavaScript , Node.js . , , Node, Ruby. : Node , Ruby, Python Java.

, Rails Node.JS? ? Node , , JavaScript Chrome . , Node.js — JavaScript C/C ++ , HTTP TCP-.

Node , . , . , .

Node.js :

• Node , , ;

• , .

(, EventMachine Ruby Twisted Python), Node .

Node.JS , , .

Node -, . (DIRT), , API JSON .

Node (NPM)

Node , . :

• , ;

• ;

• tarballs git repositories ;

• NPM.

Node.js

Node Windows OS X, . NVM ( Node).

, , . , NVM Ubuntu.

-, , C ++:

$ sudo apt-get update

$ sudo apt-get install build-essential libssl-dev

NVM :

$ curl https://raw.githubusercontent.com/creationix/nvm/v0.13.1/install.sh | hit

NVM , , , . :

$ nvm

, , . Node NPM.

:

$ nvm install v0.10.31

################################################## ################ 100,0%

npm :

$ node -v & amp; & amp; & amp; npm -v

v0.10.31

1.4.23

Node.JS :

$ nvm alias default 0.10.31

Node , , nvm use:

$ nvm install v0.8.10

, , nvm-list. , , :

list $ nvm

v0.6.3 v0.6.12 v0.6.14 v0.6.19 v0.7.7 v0.7.8 v0.7.9 v0.8.6 v0.8.11 v0.10.3 v0.10.12 v0.10.15 v0.10.21 v0.10.24 v0.11.9 : v0.10.24 default -> v0.10.24

Node.JS Java Python , PHP Ruby . Node CommonJS . , require.

, :

var http = require ('http');

var dns = require ('dns');

:

var myFile = require ('./ myFile'); // download myFile.js

NPM, - Github. :

# where express ===

$ npm install express

, , (CPS). (, ) .

IPv4- :

var dns = require ('dns');

dns.resolve4 ('www.google.com', function (err, addresses) {

if (err) throw err;

console.log ('addresses:' + JSON.stringify (addresses));

});

( ) dns.resolve4. async , , .

Node.JS , , . , , .

IRC-:

var irc = require ('irc');

var client = new irc.Client ('irc.freenode.net', 'myIrcBot', {

: ['# sample-channel']

});

client.on ('error', function (message) {

console.error ('error:', message);

});

client.on ('connect', function () {

console.log (« irc»);

});

client.on ('message', function (from, to, message) {

console.log (from + '=>' + to + ':' + message);

});

client.on ('pm', function (from, message) {

console.log (from + '=> ME: + message);

}).

:

• , IRC-;

• ;

• pm .

EventEmitter.

EventEmitter , , . , .

Node EventEmitter , EventEmitter. MemoryWatcher, EventEmitter :

• , ;

• , .

, Node - -, . JavaScript.