How to serialize Ecto record struct to make it storeable as :map in the database?

Question

I want to store an Ecto.Schema struct which is returned from Repo.get(MyModel, id).

Stuff like __meta__, association: <Association is not loaded> prevents from jsonifying it, so I catch an exception (it's reasonable). Is there any Ecto native function to get only map of record columns which I can serialize & store at the database?

Answer 1

My solution

defmodule MyApp.Schema do
  @schema_meta_fields [:__meta__]

  def to_storeable_map(struct) do
    association_fields = struct.__struct__.__schema__(:associations)
    waste_fields = association_fields ++ @schema_meta_fields

    struct |> Map.from_struct |> Map.drop(waste_fields)
  end
end