:cyclone: ws-extensions

Sec-WebSocket-Extensions header parser and serializer utils. This library aims to allow any WebSocket server implementation to parse the extensions supplied by the client decoupling the logic of parsing and checking the header value conforms to the ABNF specified in Section 9.1 of the WebSocket Protocol RFC.

Getting Started

Install ws-extensions using npm:

1npm install --save @hugmanrique/ws-extensions

Or via yarn:

1yarn add @hugmanrique/ws-extensions

The minimum supported Node version is v8.10.0.

Let's get started by parsing a header:

1import { parse } from '@hugmanrique/ws-extensions';
2const header = 'a; b=1';
3
4// [ { name: 'a', params: { b: 1 } } ]
5parse(header);

Multiple complex offers support

ws-extensions supports duplicate offers or params:

1const header = 'a; b=1, c, b; d, c; e="hey, you"; e, a; b';
2
3/*
4[ { name: 'a', params: { b: 1 } },
5  { name: 'c', params: {} },
6  { name: 'b', params: { d: true } },
7  { name: 'c', params: { e: ['hey, you', true] } },
8  { name: 'a', params: { b: true } } ]
9*/
10parse(header);

Methods

parse(header)

Parses the Sec-WebSocket-Extensions header into a JavaScript object.

• Returns an empty object if the header is empty.
• Throws a SyntaxError if the header is invalid.
• Unescapes data (numbers and flags get converted to JS primitives)
• Supports duplicate offers
• Supports duplicate params (converts the param value to an Array)

serialize(name, params)

Serializes the params of an offer.

License

MIT © Hugo Manrique