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lib | ||
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CHANGELOG.md | ||
LICENSE | ||
package.json | ||
README.md |
rfc4648.js
This library implements encoding and decoding for the data formats specified in rfc4648:
- base64
- base64url
- base32
- base32hex
- base16
Each encoding has a simple API inspired by Javascript's built-in JSON
object:
import { base32 } from "rfc4648";
base32.stringify([42, 121, 160]); // -> 'FJ42A==='
base32.parse("FJ42A==="); // -> Uint8Array([42, 121, 160])
The library has tree-shaking support, so tools like rollup.js or Webpack 2+ can automatically trim away any encodings you don't use.
- Zero external dependencies
- 100% test coverage
- Built-in types for Typescript & Flow
- 0.8K minified + gzip (can be even smaller with tree shaking)
API details
The library provides the following top-level modules:
base64
base64url
base32
base32hex
base16
codec
Each module exports a parse
and stringify
function.
const string = baseXX.stringify(data, opts)
Each stringify
function takes array-like object of bytes and returns a string.
If you pass the option { pad: false }
in the second parameter, the encoder will not output padding characters (=
).
const data = baseXX.parse(string, opts)
Each parse
function takes a string and returns a Uint8Array
of bytes. If you would like a different return type, such as plain Array
or a Node.js Buffer
, pass its constructor in the second argument:
base64.parse("AOk=", { out: Array });
base64.parse("AOk=", { out: Buffer.allocUnsafe });
The constructor will be called with new
, and should accept a single integer for the output length, in bytes.
If you pass the option { loose: true }
in the second parameter, the parser will not validate padding characters (=
):
base64.parse("AOk", { loose: true }); // No error
The base32 codec will also fix common typo characters in loose mode:
base32.parse("He1l0==", { loose: true }); // Auto-corrects as 'HELLO==='
Custom encodings
To define your own encodings, use the codec
module:
const codec = require("rfc4648").codec;
const myEncoding = {
chars: "01234567",
bits: 3
};
codec.stringify([220, 10], myEncoding); // '670050=='
codec.parse("670050", myEncoding, { loose: true }); // [ 220, 10 ]
The encoding
structure should have two members, a chars
member giving the alphabet and a bits
member giving the bits per character. The codec.parse
function will extend this with a third member, codes
, the first time it's called. The codes
member is a lookup table mapping from characters back to numbers.