class SignedGlobalID

def pick_verifier(options)

Raise ArgumentError if neither is available.
Grab the verifier from options and fall back to SignedGlobalID.verifier. 
def pick_verifier(options)
  options.fetch :verifier do
    verifier || raise(ArgumentError, 'Pass a `verifier:` option with an `ActiveSupport::MessageVerifier` instance, or set a default SignedGlobalID.verifier.')
  end
end