WebSocketsby Bodo Kaiser

What are WebSockets?

WebSockets allow bidirectional communication over HTTP!

HTTPServer

Client

GET / HTTP/1.1Host: localhostAccept: */*

HTTP/1.1 200 OKContent-Type: text/plainContent-Length: 12

WSServer

Client

GET / HTTP/1.1Host: localhostUpgrade: websocketConnection: UpgradeSec-WebSocket-Key: …Sec-WebSocket-Version:13

HTTP/1.1 101 Switching…Upgrade: websocketConnection: UpgradeSec-WebSocket-Accept: …

Frame Encoding

1000 0001 0000 0101 0100 1000 0110 0101 0111 1001

PayloadHeader

H e yF I N

R S V

OP CODE

M A S K

LENGTH

Extended Length Masking

WebSockets in node.js

socket.io by learn boost fallback support, high level api (e.g. events)

!ws by einaros

„fastest“ websocket implementation

Walve

- socket.io by learn boost not working, using xhr fallback all the time, cannot read code for PR

!- other ws implementations awful API design, also bad to read

1. Follows node’s core conventions 2. Uses node’s TransformStreams 3. Written in readable JavaScript

Designhttp.Server

„upgrade“ Event

walve.Server

walve.Response

walve.Socket

walve.Socket

walve.Incoming walve.Outgoing

„response“ Event

Some Router / Web Framework

Code Examples

Visit http://github.com/bodokaiser/node-walve ! !

!

Do not forget to leave a Start :)

Performance (Hello World)Hello World

0,000

1,000

2,000

3,000

4,000

5,000

ws walve

Performance (Small Image)Small Image

60,000

70,000

80,000

90,000

100,000

110,000

ws walve

Performance (Large Image)Large Image

Wer

teac

hse

2000,000

2400,000

2800,000

3200,000

3600,000

4000,000

4400,000

4800,000

5200,000

5600,000

6000,000

ws walve

Performance (Memory Consumption)Memory Consumption

0,0

100,0

200,0

300,0

400,0

500,0

walve ws

Further Thoughts

1. Reliability !

2. Extendability !

3. Future development !

4. Mobile Usage (ProTip)

ExamplesMessenger

!Simple WebSocket Chat with Image support.

Nearby !

Realtime Tracking with Google Maps and Geolocation.

!http://github.com/bodokaiser/messenger http://github.com/bodokaiser/nearby

Thanks and Q&A

Follow me on twitter @bodojs !

Star my projects on github github.com/bodokaiser