add: base64url support

[jrschumacher]

Using string replaceAll since base64 is external base64-js.
Dependency does not yet support base64url beatgammit/base64-js#53

[samuelscheit]

I also need base64url encoding support for my project,
@jrschumacher thank you for implementing it, I'll use your branch until this PR gets merged.

[Dabada]

Any news for this ? Please.

[ghost]

same issue, any news?

[ChrisAntaki]

Thanks for coding this, @jrschumacher! Using it for a fork

[swetshaw]

I need base64url encoding support for my project, can we review and merge this ASAP?

[jrschumacher]

It's probably not going to happen if it's been this long. Just use my branch or just wrap the base64 function in a string replace.

[TDola]

Hopefully this is merged some day. It seems to work well
npm install feross/buffer#pull/314/head

[dcousens]

LGTM, I'll need to resolve the CI issues before I can merge though

[jrschumacher]

@dcousens I removed trailing spaces on line 955 of index.js

[jrschumacher]

@dcousens still interested in taking this?

[jrschumacher]

I rebased with the master branch and removed my lint scripts from the package.json to reduce conflicts.

[dcousens]

Thanks @jrschumacher, I'm happy to take this from here next I can, I need to check in on @chjj's pull request in #349, which might supersede this

[ST-DDT]

Would it be possible to merge and release this first since the other PR seems stuck for a long time now?

[SamVerschueren]

If the goal is to make it behave like Node.js, we also need to strip and add the padding.

function base64urlToBase64 (str) {
  // Replace '-' back to '+' and '_' back to '/'
  let base64 = str
    .replaceAll(BASE64URL_CHAR_62, BASE64_CHAR_62)
    .replaceAll(BASE64URL_CHAR_63, BASE64_CHAR_63)

  // Add padding ('=') if needed
  const padding = base64.length % 4

  if (padding > 0) {
    base64 += '='.repeat(4 - padding)
  }

  return base64;
}

function base64urlFromBase64 (str) {
  return str
    .replaceAll(BASE64_CHAR_62, BASE64URL_CHAR_62)
    .replaceAll(BASE64_CHAR_63, BASE64URL_CHAR_63)
    .replace(/=+$/, '')
}

[jrschumacher]

@SamVerschueren given that this will be 3 years old this month, I'm going to close it since there doesn't seem any intention to move forward with it.

[jrschumacher]

@SamVerschueren you might want to consider adding a PR to https://github.com/feross/base64-js

[SamVerschueren]

Yeah agreed. In the mean time I created my own fork to fix the issue. Just wanted to post it as additional information for people running into the same issue.