kevva/base64-regex

Regular expression for matching base64 encoded strings

base64-regex

Regular expression for matching base64 encoded strings

Install

$ npm install --save base64-regex

Usage

const base64Regex = require('base64-regex');

base64Regex().test('dW5pY29ybg== foo bar');
//=> true

base64Regex({exact: true}).test('dW5pY29ybg== foo bar');
//=> false

base64Regex({exact: true}).test('dW5pY29ybg==');
//=> true

'foo dW5pY29ybg== bar Ym9hdA=='.match(base64Regex());
//=> ['dW5pY29ybg==', 'Ym9hdA==']

API

base64Regex([options])

Returns a regex for matching base64 encoded strings.

options

exact

Type: boolean
Default: false (Matches any base64 in a string)

Only match an exact string. Useful with RegExp#test to check if a string is a base64 encoded string.

License

MIT © Kevin Mårtensson

base64-regex's Issues

The regex can't match some base64 string

438026444 convert to base64 string is NDM4MDI2NDQ0, the regex can't match this.

This function works well.

Published version on npm is not same as in repo

index.js in the repository has an extra ? in the exact string interpolation, causing them to validate different things.

Published version: https://cdn.jsdelivr.net/npm/[email protected]/index.js
In repository: https://github.com/kevva/base64-regex/blob/0f0065cb1a1c75dc13c603c424f19103a2294782/index.js

I believe neither of the versions to be correct though, since the ? should be present in the regex for both exact and non-exact in order to match all base64 strings. Without it, it only matches 2/3 of all possible base64 strings.

File does not validate as base64

This PDF-file does not validate as a valid base64. Any idea why?

const fs = require('fs')
const base64Regex = require('base64-regex')
const b64 = fs.readFileSync('./smalltest.pdf' ,'base64')
console.log(b64) // missing == at end
console.log(base64Regex().test(b64)) // false

Regex doesn't validate base64 not ending in =

If you look at the regex, you'll see that it requires a segment that ends in a =. For example, QmCC is a valid base64 string, but this regex doesn't validate that string:

https://regex101.com/r/uGf7ne/1

However, ^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$ allows the last segment to not have to end in an =.

https://regex101.com/r/uGf7ne/2

I might also add that I've seen other people lift this regex for other uses (https://stackoverflow.com/a/29275028), which I'm also doing, thus I found this problem. In that case, it might be helpful to the greater community to make the regex more 'flavor compatible' by escaping some characters that other languages require, like so: ^(?:[A-Za-z0-9+\/]{4})*(?:[A-Za-z0-9+\/]{2}==|[A-Za-z0-9+\/]{3}=)?$

I'd be happy to create a PR if so desired.

Large base64 buffer not validate

When i try to validate large audio base64 buffer i got below error -

RangeError: Maximum call stack size exceeded

Audio file size approx 5MBb

Released version does not match inline sourcemap strings

v1.1.1 does not match sourcemap strings. The current master does. Could you release a new version?