price-point-api/app/models/vote.rb

# == Schema Information
#
# Table name: votes
#
#  id           :bigint           not null, primary key
#  direction    :integer
#  votable_type :string           not null
#  created_at   :datetime         not null
#  updated_at   :datetime         not null
#  user_id      :bigint           not null
#  votable_id   :bigint           not null
#
# Indexes
#
#  index_votes_on_user_id  (user_id)
#  index_votes_on_votable  (votable_type,votable_id)
#
# Foreign Keys
#
#  fk_rails_...  (user_id => users.id)
#
class Vote < ApplicationRecord
  belongs_to :user
  belongs_to :votable, polymorphic: true, counter_cache: true

  enum :direction, {upvote: 0, downvote: 1}

  validates :user_id, uniqueness: { scope: [:votable_type, :votable_id], message: "has already voted on this item" }
end