remove_empty_topics.rb

# This module will add a method
# to clean up empty topics:
module RemoveEmptyTopicsStorageExtension
  def remove_empty_topics
    all_topics, _topics_count = topics(limit: nil, offset: nil)
    topics_to_remove = all_topics.select { |t| t.subscriptions_count == 0 }
    if topics_to_remove.any?
      topic_names = topics_to_remove.map(&:name)
      fingerprint_key = topic_names.map { |t| fingerprints_key(t) }
      with_redis do |r|
        r.del(fingerprint_key)
        r.srem(all_topics_key, topic_names)
      end
    end
  end
end

# Add the method to GraphQL-Pro's storage class:
GraphQL::Pro::Subscriptions::RedisStorage.include(RemoveEmptyTopicsStorageExtension)

# Call the method on your schema's subscriptions system:
MySchema.subscriptions.instance_variable_get(:@storage).remove_empty_topics