Question

This is hard to explain, but I will do my best:

I am building a system where user’s can take courses. Courses are made up of steps, that must be taken in order. In the system there are 6 step types (Download, Presentation, Video, Text, Quiz, and Survey)

The way a user accesses a STEP currently is:

http://example.com/courses/2/course_steps/1

As you can tell course_steps are nested under courses.

Below is the show method in course steps:

def show
  render "show_#{@course_step.step.step_type.name.downcase}"
end

As you can tell it basically picks a view to show_[TYPE] (quiz, survey, text..etc)

This works fine for simple steps such as a text, video, or download, but for complicated steps such as a quiz, this model does not work well for the following reasons:

• How do I validate a form for a quiz or survey as I would be using a different controller (QuizAttemptsController).
• It seems to break the REST principal as a quiz, survey..etc should be treated separately. (I know they are step types, but they can have their own actions and validations)

Step Model

class Step < ActiveRecord::Base
  belongs_to :step_type
  belongs_to :client
  has_one :step_quiz, :dependent => :destroy
  has_one :step_survey, :dependent => :destroy
  has_one :step_text, :dependent => :destroy
  has_one :step_download, :dependent => :destroy
  has_one :step_video, :dependent => :destroy
  has_one :step_presentation, :dependent => :destroy
  has_many :course_steps, :dependent => :destroy
  has_many :courses, :through => :course_steps
  has_many :patient_course_steps, :dependent => :destroy

  attr_accessible :step_type_id, :client_id, :title, :subtitle, :summary

  validates :title, :presence=>true
  validates :summary, :presence=>true

  def getSpecificStepObject()
    case self.step_type.name.downcase
      when "text"
        return StepText.find_by_step_id(self.id)
      when "quiz"
        return StepQuiz.find_by_step_id(self.id)
      when "survey"
        return StepSurvey.find_by_step_id(self.id)
      when "download"
        return StepDownload.find_by_step_id(self.id)
      when "video"
        return StepVideo.find_by_step_id(self.id)
      when "presentation"
        return StepPresentation.find_by_step_id(self.id)
    end
  end
end

Step Quiz Model:

class StepQuiz < ActiveRecord::Base
  belongs_to :step, :dependent => :destroy
  has_many :step_quiz_questions, :dependent => :destroy
  has_many :quiz_attempts, :dependent => :destroy

  accepts_nested_attributes_for :step
  accepts_nested_attributes_for :step_quiz_questions, :allow_destroy => true
  attr_accessible :step_id, :instructions, :step_attributes, :step_quiz_questions_attributes
  validates :instructions, :presence=>true
end

CourseStep Model

class CourseStep < ActiveRecord::Base
  belongs_to :step
  belongs_to :course

  validates_uniqueness_of :step_id, :scope => :course_id

  def next_step()
    Course.find(self.course.id).course_steps.order(:position).where("position >= ?", self.position).limit(1).offset(1).first
  end

  def previous_step()
     Course.find(self.course.id).course_steps.order("position DESC").where("position <= ?", self.position).limit(1).offset(1).first
  end
end

How would you suggest fixing this?

Answer 1

One way I have solved the problem is by adding a member action of “submit_quiz”to the course_steps controller. I am not sure if I like this, as the code looks kind of ugly. I would appreciate feedback.(Note: I Am using CanCan so @course_step is created automagically in the course_steps_controller)

The things I don’t like are:

• show_quiz view has a lot of code in it
• submit_quiz is in the course_steps_controller
• quiz_attempt model has virtual attribute of quiz_questions (for validation purposes)

show_quiz.html.erb

<%= form_for (@quiz_attempt.blank? ? QuizAttempt.new(:started => Time.now.utc, :step_quiz_id => @course_step.step.step_quiz.id) : @quiz_attempt, :url => submit_quiz_course_course_step_path(@course_step.course, @course_step)) do |f| %>
<%= render :partial => 'shared/error_messages', :object => f.object %>
    <% @course_step.step.step_quiz.step_quiz_questions.each do |quiz_question| %>
        <h3><%= quiz_question.value %></h3>
        <% quiz_question.step_quiz_question_choices.each do |quiz_question_choice| %>
        <%= radio_button_tag("quiz_attempt[quiz_questions][#{quiz_question.id}]", quiz_question_choice.value, f.object.get_quiz_question_choice(quiz_question.id) == quiz_question_choice.value)%>
        <%= quiz_question_choice.value %><br />
        <% end %>

    <% end %>
    <%= f.hidden_field(:step_quiz_id)%>
    <%= f.hidden_field(:started)%>
    <%= submit_tag("Submit Quiz")%>
<% end %>

course_steps_controller.rb

 def show
    PatientCourseStep.viewed(current_user.id, params[:course_id], @course_step.step.id )
    render "show_#{@course_step.step.step_type.name.downcase}"
  end

  def submit_quiz
    @quiz_attempt = QuizAttempt.new(params[:quiz_attempt])

    if !@quiz_attempt.save()
      render 'show_quiz'
    end
  end

quiz_attempt.rb

class QuizAttempt < ActiveRecord::Base
  belongs_to :step_quiz
  belongs_to :patient

  attr_accessor :quiz_questions
  attr_accessible :step_quiz_id, :patient_id, :started, :ended, :correct, :incorrect, :quiz_questions

  validate :answered_all_questions?

  def get_quiz_question_choice(quiz_question_id)
    unless self.quiz_questions.blank?
      quiz_questions[quiz_question_id.to_s]
    end
  end

  private
    def answered_all_questions?
      #Making sure they answered all the questions
      if self.quiz_questions.blank? or self.quiz_questions.try(:keys).try(:count) != self.step_quiz.step_quiz_questions.count
        errors.add_to_base "Not all questions were answered"
    end
  end
end


  def submit_quiz
    @quiz_attempt = QuizAttempt.new(params[:quiz_attempt])

    if !@quiz_attempt.save()
      render 'show_quiz'
    end
  end