def signing_request
      req = OpenSSL::X509::Request.new
      req.public_key = key.public_key
      req.subject = OpenSSL::X509::Name.new([['CN', domain]])
      req.sign(key, OpenSSL::Digest::SHA256.new)
    end
def signing_request
      req = OpenSSL::X509::Request.new
      req.public_key = key.public_key
      req.subject = OpenSSL::X509::Name.new([['CN', domain]])
      req.sign(key, OpenSSL::Digest::SHA256.new)
    end
Generate a new certificate signing request (CSR) which will be picked
 up by the certificate subject and public key.