records participation of user via web

answering a poll question creates a voter with the user data to record
participation in question’s poll

app/controllers/polls/questions_controller.rb

@@ -19,6 +19,7 @@ class Polls::QuestionsController < ApplicationController
 
     answer.answer = params[:answer]
     answer.save!
+    answer.record_voter_participation
 
     @answers_by_question_id = {@question.id => params[:answer]}
   end

app/models/poll/answer.rb

@@ -3,6 +3,10 @@ class Poll::Answer < ActiveRecord::Base
   belongs_to :question, -> { with_hidden }
   belongs_to :author, ->   { with_hidden }, class_name: 'User', foreign_key: 'author_id'
 
+  has_one :voter
+
+  delegate :poll, :poll_id, to: :question
+
   validates :question, presence: true
   validates :author, presence: true
   validates :answer, presence: true
@@ -10,4 +14,8 @@ class Poll::Answer < ActiveRecord::Base
 
   scope :by_author, -> (author_id) { where(author_id: author_id) }
   scope :by_question, -> (question_id) { where(question_id: question_id) }
+
+  def record_voter_participation
+    Poll::Voter.create_from_user(author, {poll_id: poll_id, answer_id: id})
+  end
 end