ws-frame

A class used to represent a websocket frame.

Usage

// server.js
const net = require('net');
const Frame = require('ws-frame');
const server = new net.Server();

server.on('connection', socket => {
  socket.on('data', buffer => {
    let payload;
    const frame = new Frame(buffer);

    if(!frame.mask){
        ... // bad request code
    } else if(frame.fin) {
      const payload = frame.payload;
      console.log(payload.toString());
    }
  })

})

server.listen(4000);

// client.js
const net = require('net');
const socket = new net.Socket();
const MASKING_KEY = Buffer.From('some masking key');
let mFrame;

socket.connect({ port: 4000 });

socket.on('data', buf => {
  let message;
  const frame = new Frame(buf);

  if(frame.opcode) {
    mFrame = frame;
  } else {
    mFrame.concat(frame.payload)
  }

  if(frame.fin){
    message = mFrame.payload.toString();
    ... // do something with message
    if(frame.opcode === PING){
      mFrame.opcode = PONG;
      mFrame.payload = Buffer.from('pong message?');
      mFrame.maskingKey = MASKING_KEY;
    } else {
      mFrame = new Frame({
        maskingKey: MASKING_KEY,
        payload: appData
      });
    }
    socket.write(mFrame.toBuffer());
  }
})

Class: Frame

new Frame(options|Buffer)

The Frame constructor accepts an options object(plain object) or a Buffer.

• options
  • fin: 0 or 1
  • rsv1: 0 or 1
  • rsv2: 0 or 1
  • rsv3: 0 or 1
  • mask: 0 or 1
  • opcode: 0 ... 15 inclusively
  • maskingKey: String or Buffer
  • payload: String or Buffer constrictor accepts a plain object or buffer

Frame Properties

Properties| Setter accepts | Getter returns ----------|----------------|--------------- fin| Number - 0 or 1| Number - 0 or 1 rsv1| Number - 0 or 1| Number - 0 or 1 rsv2| Number - 0 or 1| Number - 0 or 1 rsv3| Number - 0 or 1| Number - 0 or 1 mask| Number - 0 or 1| Number - 0 or 1 opcode| Number - 0 or 15| Number - 0 or 15 payloadLength| N/A| Number maskingKey|String or Buffer| Buffer payload|String or Buffer| Buffer

Frame Instance Methods

removePayload(): removes a frame's payload.

removeMaskingKey(): removes a frame's maskingKey and unmasks its payload if it was masked.

concat(Buffer): appends a buffer to a frame's payload.

toBuffer(): returns a buffer representation of a frame.

isValid(): returns true if a frame is valid and false otherwise.

toString(): returns a string representation of a frame.