# File lib/aws/s3/client.rb, line 52 def sign_request request version = @config.s3_signature_version ? @config.s3_signature_version.to_sym : (@region =~ /cn-/ ? :v4 : :v3) case version when :v4 then v4_signer.sign_request(request) when :v3 then v3_signer.sign_request(request) else raise "invalid signature version #{version.inspect}" end end