absl::string_view host_address, Envoy::Http::ResponseHeaderMap& headers) {

  const bool host_changed =

      !upstream_address_.has_value() || host_address != upstream_address_.value();

  if (host_changed) {

    const std::string encoded_address =

        Envoy::Base64::encode(host_address.data(), host_address.length());

    headers.setCopy(factory_.getHeaderName(), encoded_address);

  }

  return host_changed;

}

    : name_(config.name()) {

  if (config.name().empty()) {

    throw EnvoyException("Header name cannot be empty for header based stateful sessions");

  }

}