You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
89 lines
2.8 KiB
89 lines
2.8 KiB
2 weeks ago
|
# rfc4648.js
|
||
|
|
|
||
|
|
[](https://travis-ci.com/swansontec/rfc4648.js)
|
||
|
|
[](https://standardjs.com)
|
||
|
|
|
||
|
|
This library implements encoding and decoding for the data formats specified in [rfc4648](https://tools.ietf.org/html/rfc4648):
|
||
|
|
|
||
|
|
- base64
|
||
|
|
- base64url
|
||
|
|
- base32
|
||
|
|
- base32hex
|
||
|
|
- base16
|
||
|
|
|
||
|
|
Each encoding has a simple API inspired by Javascript's built-in `JSON` object:
|
||
|
|
|
||
|
|
```js
|
||
|
|
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](https://rollupjs.org/) or [Webpack 2+](https://webpack.js.org/) 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:
|
||
|
|
|
||
|
|
```js
|
||
|
|
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 (`=`):
|
||
|
|
|
||
|
|
```js
|
||
|
|
base64.parse("AOk", { loose: true }); // No error
|
||
|
|
```
|
||
|
|
|
||
|
|
The base32 codec will also fix common typo characters in loose mode:
|
||
|
|
|
||
|
|
```js
|
||
|
|
base32.parse("He1l0==", { loose: true }); // Auto-corrects as 'HELLO==='
|
||
|
|
```
|
||
|
|
|
||
|
|
### Custom encodings
|
||
|
|
|
||
|
|
To define your own encodings, use the `codec` module:
|
||
|
|
|
||
|
|
```js
|
||
|
|
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.
|