Sort by has_many relationship causes wrong query

[CV-Gate]

As an example:

/api/indicators?sort=widgets.title

results in this query:

SELECT "indicators".* FROM "indicators" LEFT JOIN widgets AS widgets_sorting ON widgets_sorting.id = indicators.indicator_id ORDER BY widgets_sorting.title asc

As you can see, it should be indicators.id and not indicators.indicators_id

This doesn't happen if sort is done by a has_one relation.

[CV-Gate]

Temporary fixed by:

  def self._build_joins(associations)
    joins = []

    associations.inject do |prev, current|
      if current.class == ActiveRecord::Reflection::HasOneReflection
        joins << "LEFT JOIN #{current.table_name} AS #{current.name}_sorting ON #{current.name}_sorting.#{current.foreign_key} = #{prev.table_name}.id"
      else
        joins << "LEFT JOIN #{current.table_name} AS #{current.name}_sorting ON #{current.name}_sorting.id = #{prev.table_name}.id"
      end
      current
    end
    joins.join("\n")
  end

Inspired by @fsauter here: https://github.com/cerebris/jsonapi-resources/issues/1086#issuecomment-314271863