Rendering recursive relations about panko_serializer

[daniel-koudouna]

As an update, I was able to recursively render children of the same model by defining them as an attribute and using a method as below:

# frozen_string_literal: true

class CommentSerializer < Panko::Serializer
  attributes :id, :children

  def children
    Panko::ArraySerializer.new(object.children, each_serializer: CommentSerializer).to_a
  end
end

I am not sure what the impact to performance this would have, but it seems to be working with no issues for now. Let me know if there is a better way of doing this, I would think this is quite a common use case.

[yosiat]

Hey @daniel-koudouna !

First I am sorry for long reply time, I have looked at the bug here and looks like this happen because I am building a "serialization descriptor" (contains attributes, associations and their serializer info) ahead of time and not lazily, from first look it looks like a big one to fix.

I'll try to experiment with multiple options to solve this, but don't have promise of solution for the near-time.

Regarding your suggested solution, it works, but it's not efficient as it could be, since has_many builds the json-string incrementally (using Oj::StringWriter) and with your approach it will serialize the children to array of hashes and then to JSON. I might be able to have quick release to address by doing something like:

class CommentSerializer < Panko::Serializer
  attributes :id, :children

  def children
     serialized_json = Panko::ArraySerializer.new(object.children, each_serializer: CommentSerializer).to_json
     Panko::JsonValue.from(serialized_json)
  end
end

which will be more efficient, if this something that interests you, let me know and I'll work on it.