Sample Server container policy file

gtmContainerPolicy.js

gtag('policy', 'all', function(container, policy, data) {
  switch (policy) {

    // Only allow _ga cookie to be set.
    case 'set_cookies':
      return data.name === '_ga';

    // All other permission requests are allowed.
    case 'access_response':
    case 'access_template_storage':
    case 'get_cookies':
    case 'logging':
    case 'use_message':
    case 'read_container_data':
    case 'read_event_data':
    case 'read_event_metadata':
    case 'read_request':
    case 'return_response':
    case 'run_container':
    case 'send_http':
    default:
      return true;
  }
});