An alternative to the default socket.io-parser, encoding and decoding packets with JSON.parse / stringify.

With that parser, binary data (ArrayBuffer / Buffer / Blob / File) is not supported.

Please note that you MUST use the parser on both sides (server & client).

See also:

• the default parser: https://github.com/socketio/socket.io-parser
• a parser based on msgpack: https://github.com/darrachequesne/socket.io-msgpack-parser

const io = require('socket.io');
const ioc = require('socket.io-client');
const customParser = require('socket.io-json-parser');
const server = io(PORT, {
  parser: customParser
});
const socket = ioc('ws://localhost:' + PORT, {
  parser: customParser
});
socket.on('connect', () => {
  socket.emit('hello');
});

socket.emit('hello', 'you') will create the following packet:

{
  "type": 2,
  "nsp": "/",
  "data": ["hello", "you"]
}

which will be encoded by the parser as:

{"type":2,"nsp":"/","data":["hello","you"]}

More information about the exchange protocol can be found here.