Creating AuthRequests with nil RelayState sends empty RelayState URL param

[vincentwoo]

Doing OneLogin::RubySaml::Authrequest.new.create(settings, RelayState: nil) still creates an empty RelayState url param. Ideally nil (or perhaps even falsy) RelayState would cause ruby-saml to not output a param. This caused an issue for a customer integration recently. SimpleSaml (the PHP library) apparently decided that we had an improperly signed request with the empty param.

[pitbulk]

We should definitely avoid to generate TX with empty RelayState URL parameters.

When we generate the url_string we use the build_query that doesn't add the RelayState parameter if there is no content.

but the issue is after that, at the

params.each_pair do |key, value|
    request_params[key] = value.to_s
end

where params has the RelayState value, so if null set a null value for that parameter to request_params.

Similar issue happens at LogoutRequest and LogoutResponse

@vincentwoo are you able to provide a PR to fix that? Maybe makes sense some refactor.

[vincentwoo]

Scratch last comment, got tests working w/ bundle exec