Всеволод Струкчинский: Node.js

@floatdrop
bit.ly/nodejs-‐‑shri

1
2 on mouseUp
3
get the selection
4
if it is empty then as "Dial what number?"
5
if it is not empty then
6
push this card
7
visual effect zoom open
8
go to stack "Phone"
9
dial it
10
pop card
11
end if
12 end mouseUp
13

1987

Расчитан на обработку событий

1995

Был написан за

1995

дней


10 дней

1995


10

дней
Function as first-‐‑class objects

1995


10

дней
Function as first-‐‑class objects
Прототипное наследование из Self

1995

Node.JS
JavaScript on server

2009

index.php
1
2
3
4
5
6
7
8
9

$result = mysqli_query( $con,
"SELECT * FROM Persons");
while($row = mysqli_fetch_array($result)) {
echo $row['Name']."n";
}
file_put_contents("access.log",
"Request done")

Single-‐‑thread server

Pictures from node-‐‑explained

Ryan Dahl

I/O has to be done differently.
We are doing it wrong

Ryan Dahl

I/O has to be done differently.
We are doing it wrong

bit.ly/jsconf-‐‑node

event-‐‑loop сервер

event-‐‑loop server
goes wrong

JavaScript is slow

bit.ly/bombanulo-‐‑2

"ʺSimple"ʺ benchmark

bit.ly/dumb-‐‑test

Installing

nodejs.org/download

Modules
require('ʹantigravity'ʹ)

module.js
1
2
3
4
5

function HelloWorld () {
console.log('Hello world');
}
console.log('Module loaded');

index.js
1

require('./module');

index.js
1
2
3

require('./module');
HelloWorld();

module.js
1
2
3
4
5
6
7

}
exports.HelloWorld = HelloWorld;

index.js
1
2
3

var module = require('./module');
module.HelloWorld();

module.js
1
2
3
4
5
6
7

}
global.HelloWorld = HelloWorld;

exports vs module.exports
russian.js
1
2
3
4
5
6

var en_translation = {
yes: 'Нет',
no: 'Да'
};
exports = en_translation;

russian.js
1
2
3
4
5
6

var en_translation = {
yes: 'Да',
no: 'Нет'
};
module.exports = en_translation;

russian.json
{
"yes": "да",
"no": "нет"
}

requrie('ʹ./directory'ʹ)
3. require('ʹ./directory/index.json'ʹ)

2. require('ʹ./directory/index.js'ʹ)

2. require('ʹ./directory/index.js'ʹ)
1. require('ʹ./directory/'ʹ +
require('ʹ./directory/package.json'ʹ).main);

require('http')
require('express')
require('./index.js')
require('./config.json')
require('./module') // Directory

Simple web-‐‑server
index.js
1
2
3
4
5
6
7
8
9

var http = require('http');
function helloService(request, response) {
response.end("Hello, stranger!");
}
var server = http.createServer(helloService);
module.exports = server;

Simple web-‐‑server
node_modules

require("ʺantigravity"ʺ)
in /home/user/programm/library/index.js

1. /home/user/programm/library/node_modules/antigravity

2. /home/user/programm/node_modules/antigravity

3. /home/user/node_modules/antigravity

4. /home/node_modules/antigravity

5. /node_modules/antigravity

NODE_PATH

NODE_PATH
$HOME/.node_modules, $HOME/.node_libraries, $PREFIX/lib/node

node_modules/antigravity.js
1

module.exports = new Date();

index.js
1

console.log(require("antigravity"));

node_modules/antigravity.js
1
2
3

console.log(module);
module.exports = new Date();

Circular dependencies
a.js
1
2

var b = require('./b.js');
console.log("B: ", b);

b.js
1
2

var a = require('./a.js');
console.log("A: ", a);

Circular dependencies
a.js
1
2
3
4

module.exports.hello = "Hello from A";
var b = require('./b.js');
module.exports.helloFromB = b.hello;
console.log("B: ", b);

b.js
1
2
3
4

module.exports.hello = "Hello from B";
var a = require('./a.js');
module.exports.helloFromA = a.hello;
console.log("A: ", a);

Nested dependencies
pros / cons

Nested dependencies
pros / cons
+ Version independent

Nested dependencies
pros / cons
+ Version independent
-‐‑ Wieght more

package.json
{

}

"name": "express",
"version": "3.4.4",
"dependencies": {
"connect": "2.11.0", "commander": "1.3.2", "range-parser
},
"devDependencies": {
"ejs": "*", "mocha": "*", "jade": "0.30.0", "hjs": "*", "
},
"main": "index",
"bin": {
"express": "./bin/express"
},
"scripts": {
"prepublish": "npm prune",
"test": "make test"
},
"engines": {
"node": "*"
}

Express application
var express = require('express');
var app = express();
app.get('/', function(req, res) { res.end('Hello!'); });
app.listen(3000);

joyent/node -‐‑ node.cc

joyent/node -‐‑ env-‐‑inl.h

joyent/libuv -‐‑ loop.c

joyent/libuv -‐‑ loop.c
1 static int uv__loop_init(uv_loop_t* loop, int default_loop) {
2
// ...
3
RB_INIT(&loop->timer_handles);
4
QUEUE_INIT(&loop->wq);
5
QUEUE_INIT(&loop->active_reqs);
6
QUEUE_INIT(&loop->idle_handles);
7
QUEUE_INIT(&loop->async_handles);
8
QUEUE_INIT(&loop->check_handles);
9
QUEUE_INIT(&loop->prepare_handles);
10
QUEUE_INIT(&loop->handle_queue);
11
QUEUE_INIT(&loop->pending_queue);
12
QUEUE_INIT(&loop->watcher_queue);
13
14
err = uv__platform_loop_init(loop, default_loop);
15
// ...
16 }

uv__platform_loop_init
kqueue
epoll

joyent/node -‐‑ core.c

: 258

1 int uv_run(uv_loop_t* loop, uv_run_mode mode) {
2
r = uv__loop_alive(loop);
3
while (r != 0 && loop->stop_flag == 0) {
4
// ...
5
uv__update_time(loop);
6
uv__run_timers(loop);
7
uv__io_poll(loop, timeout);
8
// ...
9
}
10 }
1
2
3
4
5

static int uv__loop_alive(uv_loop_t* loop) {
return uv__has_active_handles(loop) ||
uv__has_active_reqs(loop) ||
loop->closing_handles != NULL;
}

Fibonacci
1
2
3
4
5
6
7
8
9
10

function fibonacci(n) {
if (n < 2)
return 1;
else
return fibonacci(n-2) + fibonacci(n-1);
}
require('http').createServer(function (req, res) {
res.end("40: " + fibonacci(40));
}).listen(8005);

Fibonacci
Requests per second: 0.61
Time per request: 1634.748 ms (vs 5676 ms)

setTimeout, setImmediate,
process.nextTick

1. process.nextTick*
2. Input / Output

2. Input / Output
3. setImmediate

2. Input / Output
3. setImmediate
4. setTimeout

Fibonacci
1
2
3
4
5
6
7
8
9
10
11
12

function fibonacci(i, n, f1, f2, res) {
if (i >= n)
res.end(n + ": " + (f1 + f2));
else
setImmediate(function() {
fibonacci(i + 1, n, f2, f1 + f2, res);
});
}
require('http').createServer(function (req, res) {
fibonacci(0, 1473, 1, 1, res);
}).listen(8005);

Fibonacci
Requests per second: 264.55
Time per request: 3.780 ms

Streams
bit.ly/streams-‐‑node

Streams
0.10.x
bit.ly/streams-‐‑node

1

$ cut -f 1 | uniq -c | sort -n

Streams in Node.JS
1. fs -‐‑ createReadStream, createWriteStream

Streams in Node.JS
2. process -‐‑ stdin, stderr and stdout

Streams in Node.JS
3. http -‐‑ client requests, server response

Streams in Node.JS
4. tcp -‐‑ sockets

Streams in Node.JS
5. zlib -‐‑ createUnzip...

Streams in Node.JS
5. zlib -‐‑ createUnzip...
6. crypto -‐‑ createCipher

Crypto service
1

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

Crypto service
1


1
2
3
4

app.post('/:algo/:secret', function(req, res) {
// Some magic should be applied here
res.end(req.params.algo + " " + req.params.secret);
});

Crypto service
1


1
2
3
4

app.post('/:algo/:secret', function(req, res) {
// Some magic should be applied here
res.end(req.params.algo + " " + req.params.secret);
});

1

app.listen(31337);

Crypto stdin
1
2
3
4
5
6

var cipher = require('crypto')
.createCipher('aes192', 'secret');
process.stdin.pipe(cipher).pipe(process.stdout);

Crypto service
1


1
2
3
4
5

app.get('/:algo/:secret', function(req, res) {
var cipher = require('crypto')
.createCipher(req.params.algo, req.params.secret);
req.pipe(cipher).pipe(res);
});

1

app.listen(31337);

Streams in Node.JS are Push

ReadableStream. Events:
data, end, close, error, readable

ReadableStream
data event
1
2
3
4

process.stdin.on('data',
function(chunk) {
console.log(chunk);
});

WriteableStream. Events
finish, pipe, unpipe, drain

WriteableStream. Methods
write method
1

var backpressure = process.stdout.write('data');

Writeable stream
backpressure
1


Writeable stream
backpressure
1


This return value is strictly advisory. You MAY continue
to write, even if it returns false. However, writes will be
buffered in memory, so it is best not to do this
excessively. Instead, wait for the drain event before
writing more data.

Всеволод Струкчинский: Node.js

Recommandé

Recommandé

Contenu connexe

Tendances

Tendances (20)

En vedette

En vedette (8)

Similaire à Всеволод Струкчинский: Node.js

Similaire à Всеволод Струкчинский: Node.js (20)

Plus de Yandex

Plus de Yandex (20)

Всеволод Струкчинский: Node.js