initializer broken by ruby-jwt api changes

[subuta]

I found config.token_secret_signature_key was broken by ruby-jwt API updates ...

# config.token_secret_signature_key = -> { JWT.base64url_decode Rails.application.secrets.auth0_client_secret }

Latest ruby-jwt(v1.5.3) completely removes base64url_decode method from JWT module(at this PR)

BTW, We may use these work around as a temporary solution :)
(we may have better solution for this problem...)

require 'base64'

# extracted from original [method](http://www.rubydoc.info/github/jwt/ruby-jwt/JWT.base64url_decode)
config.token_secret_signature_key = -> {
    secret = Rails.application.secrets.auth0_client_secret
    secret += '=' * (4 - secret.length.modulo(4))
    Base64.decode64(secret.tr('-_', '+/'))
  }

[solsberg]

Thanks for the workaround, works for me also

[nsarno]

There's an issue open in ruby-jwt (jwt/ruby-jwt#133) because of 1.5.3 breaking compatibility with 1.5.2. The breaking version is going to be yanked and re-released as 1.6.0 so it should be all good after that.

I'll let this issue open for people to see the workaround in the meantime. Thanks for your help @subuta !

[nsarno]

jwt/ruby-jwt#133