app/serializers/api/v1/leagues/roster_serializer.rb
module API
module V1
module Leagues
class RosterSerializer < ActiveModel::Serializer
type :roster
attributes :id, :team_id, :name, :description, :disbanded
attribute(:division) { object.division.name }
has_many :users, key: :players, serializer: UserSerializer
has_many :matches, serializer: MatchSerializer
end
end
end
end