private static function getPageStreamingDescriptors() { $listTopicsPageStreamingDescriptor = new PageStreamingDescriptor(['requestPageTokenField' => 'page_token', 'requestPageSizeField' => 'page_size', 'responsePageTokenField' => 'next_page_token', 'resourceField' => 'topics']); $listTopicSubscriptionsPageStreamingDescriptor = new PageStreamingDescriptor(['requestPageTokenField' => 'page_token', 'requestPageSizeField' => 'page_size', 'responsePageTokenField' => 'next_page_token', 'resourceField' => 'subscriptions']); $pageStreamingDescriptors = ['listTopics' => $listTopicsPageStreamingDescriptor, 'listTopicSubscriptions' => $listTopicSubscriptionsPageStreamingDescriptor]; return $pageStreamingDescriptors; }