need to require 'forwardable' to use Forwardable

[mikegee]

I get an error from JWT 2.2.0 on Ruby 2.3 and 2.5.

JWT::JWK::RSA extends Forwardable, but there is no require 'forwardable' in the gem. I worked around this in my script by explicitly requiring forwardable.

This fails:

% docker run --rm -it ruby:2.3 ruby -e 'class MyClass; extend Forwardable; end'
-e:1:in `<class:MyClass>': uninitialized constant MyClass::Forwardable (NameError)
	from -e:1:in `<main>'

This doesn't fail:

% docker run --rm -it ruby:2.3 ruby -e 'require "forwardable"; class MyClass; extend Forwardable; end'

[excpt]

Which version of openssl is installed in you environment?

Please try to update it to version ~> 2.1.

[mikegee]

Looks like the official Ruby 2.3 docker image comes with OpenSSL 1.1.1:

% docker run --rm -it ruby:2.3 ruby -ropenssl -e'puts OpenSSL::VERSION'
1.1.1

I'm not interested in updating a system library, nor do I understand how it is related, since require 'forwardable' resolves the problem.

[btyy77c]

I've had the same problem: https://github.com/railscltgroup/firebase_auth/blob/master/lib/firebase_ruby_auth.rb
JWT 2.2.0 and Ruby 2.6.2

I have a similar file in a personal Rails app. I don't get any errors in my Rails app. However, when I'm just working on this gem, the require 'jwt' command errors out. require 'forwardable' seems to fix the error.

[excpt]

@mikegee @btyy77c

Version 2.2.1 just released. This should fix he missing dependency issue for you.

Thanks for the detailed reporting!