Provides functionality to sort Ecto queries based on user-defined rules.

This module allows sorting queries using predefined default fields (handled by FatOrderBy) and custom fields (handled by a fallback function).

Usage

defmodule MyApp.SortQuery do
  <!-- needed if you are writing queries in override_sortable -->
  import Ecto.Query
  use FatEcto.FatQuery.Sortable,
    sortable_fields: %{"id" => "$asc", "name" => ["$asc", "$desc"]},
    overrideable_fields: ["custom_field"]

  @impl true
  def override_sortable(query, field, operator) do
    case {field, operator} do
      {"custom_field", "$asc"} ->
        from(q in query, order_by: [asc: fragment("?::jsonb->>'custom_field'", q)])
      _ ->
        query
    end
  end
end

Example

query = from(u in User)
sort_params = %{"id" => "$asc", "name" => "$desc", "custom_field" => "$asc"}
MyApp.SortQuery.build(query, sort_params)

This will sort the query by id in ascending order, name in descending order, and apply custom sorting for custom_field.