Spring2019 E1907 refactor response controller
Introduction
Expertiza is an open source webapp that was built on Ruby on Rails stack. It provides a platform to students with various features like peer-reviewing projects, submitting work, form teams, viewing grades, etc. The project is maintained by students and faculty at NCSU.
Project Summary
The file response_controller.rb handles the operations on responses based on user permissions. The user is redirected to the appropriate place on Expertiza after the action is complete. The responses are from the completion of peer reviews and questionnaires. The controller takes care of tasks such as creating, saving, editing, updating and deleting these responses.
Project Tasks
The problem statement for E 1907 can be viewed here https://docs.google.com/document/d/1SeIPiccoujhJZgdb3WzWBkg2v8TKSn5SwcHBeX9kzJQ/edit?usp=sharing
The pull request of our project can be viewed here https://github.com/expertiza/expertiza/pull/1414
Task 1
Problem:
edit_allowed function The function name is misleading - it checks if the response can be viewed by a person or not. Refactor to a more appropriate name.
def edit_allowed?(map, user_id)
...
end
Solution:
The edit_allowed? function was renamed to view_allowed? in the response_controller.rb file.
def view_allowed?(map, user_id)
...
end
Task 2
Problem:
Move the pending_surveys function to survey_deployment_contoller.rb. Ensure that moving the function does not break the code functionalities.
The original code for the pending_surveys method in the response_controller.rb is shown below.
def pending_surveys
unless session[:user] # Check for a valid user
redirect_to '/'
return
end
@surveys = [] # Get all the course survey deployments for this user
[CourseParticipant, AssignmentParticipant].each do |participant_type| # Get all the participant(course or assignment) entries for this user
participants = participant_type.where(user_id: session[:user].id)
next unless participants
participants.each do |p|
survey_deployment_type = (participant_type == CourseParticipant ? CourseSurveyDeployment : AssignmentSurveyDeployment)
survey_deployments = survey_deployment_type.where(parent_id: p.parent_id)
next unless survey_deployments
survey_deployments.each do |survey_deployment|
next unless survey_deployment && Time.zone.now > survey_deployment.start_date && Time.zone.now < survey_deployment.end_date
@surveys <<
[ 'survey' => Questionnaire.find(survey_deployment.questionnaire_id),
'survey_deployment_id' => survey_deployment.id,
'start_date' => survey_deployment.start_date,
'end_date' => survey_deployment.end_date,
'parent_id' => p.parent_id,
'participant_id' => p.id,
'global_survey_id' => survey_deployment.global_survey_id ]
end
end
end
end
Solution:
Moved the pending_surveys function to survey_deployment_controller.rb
Made changes in the following files and folders:
- app/controllers/survey_deployment_controller.rb (the pending_surveys method was moved to this file)
- app/controllers/response_controller.rb
Original -
elsif params[:return] == "survey"
redirect_to controller: 'response_controller', action: 'pending_surveys'
else
New -
elsif params[:return] == "survey"
redirect_to controller: 'survey_deployment', action: 'pending_surveys'
else
- config/routes.rb
Original -
collection do
get :list
get :reminder_thread
end
New -
collection do
get :list
get :reminder_thread
get :pending_surveys
end
- spec/controllers/respose_controller_spec.rb
Original -
context 'when params[:return] is survey' do
it 'redirects to response_controller#pending_surveys page' do
@params[:return] = 'survey'
get :redirect, @params
expect(response).to redirect_to('/response_controller/pending_surveys')
end
end
New -
context 'when params[:return] is survey' do
it 'redirects to survey_deployment#pending_surveys page' do
@params[:return] = 'survey'
get :redirect, @params
expect(response).to redirect_to('/survey_deployment/pending_surveys')
end
end
- Moved pending_surveys.html.erb from views/response to views/survey_deployment
Task 3
Problem:
The assign_instance_variables method violates several principles - The method is doing two things, and the method is not really needed at all. It is called only in two places and does entirely different things based on where it is called from.
The original assign_instance_vars method is shown below:
# assigning the instance variables for Edit and New actions
def assign_instance_vars
case params[:action]
when 'edit'
@header = 'Edit'
@next_action = 'update'
@response = Response.find(params[:id])
@map = @response.map
@contributor = @map.contributor
when 'new'
@header = 'New'
@next_action = 'create'
@feedback = params[:feedback]
@map = ResponseMap.find(params[:id])
@modified_object = @map.id
end
@return = params[:return]
end
Solution:
The assign_instance_vars method was removed as it was not needed. The logic from this method was combined with the Edit and New sections as shown below.
The edit method with modifications.
def edit
# instance variables for Edit action
@header = 'Edit'
@next_action = 'update'
@response = Response.find(params[:id])
@map = @response.map
@contributor = @map.contributor
@prev = Response.where(map_id: @map.id)
@review_scores = @prev.to_a
if @prev.present?
@sorted = @review_scores.sort {|m1, m2| m1.version_num.to_i && m2.version_num.to_i ? m2.version_num.to_i <=>
m1.version_num.to_i : (m1.version_num ? -1 : 1) }
@largest_version_num = @sorted[0]
end
@modified_object = @response.response_id
# set more handy variables for the view
set_content
@review_scores = []
@questions.each do |question|
@review_scores << Answer.where(response_id: @response.response_id, <br> question_id: question.id).first
end
@questionnaire = set_questionnaire
render action: 'response'
end
Moved assign_instance_vars for the New action inside the new method : -
def new
# instance variable for New action
@header = 'New'
@next_action = 'create'
@feedback = params[:feedback]
@map = ResponseMap.find(params[:id])
@modified_object = @map.id
set_content(true)
@stage = @assignment.get_current_stage(SignedUpTeam.topic_id(@participant.parent_id, @participant.user_id)) if @assignment
team = AssignmentTeam.find(@map.reviewee_id)
@response = Response.where(map_id: @map.id, round: @current_round.to_i).order(updated_at: :desc).first
if @response.nil? || team.most_recent_submission.updated_at > @response.updated_at
@response = Response.create(map_id: @map.id, additional_comment: '', round: @current_round, is_submitted: 0)
end
questions = sort_questions(@questionnaire.questions)
init_answers(questions)
render action: 'response'
end
Task 4
Problem:
In the create() code in create method, especially the was_submitted and is_submitted part, is hard to understand. It can be cleaned up.
The original code of the create method is shown below.
def create
map_id = params[:id]
map_id = params[:map_id] unless params[:map_id].nil? # pass map_id as a hidden field in the review form
@map = ResponseMap.find(map_id)
if params[:review][:questionnaire_id]
@questionnaire = Questionnaire.find(params[:review][:questionnaire_id])
@round = params[:review][:round]
else
@round = nil
end
is_submitted = (params[:isSubmit] == 'Yes')
was_submitted = false
# There could be multiple responses per round, when re-submission is enabled for that round.
# Hence we need to pick the latest response.
@response = Response.where(map_id: @map.id, round: @round.to_i).order(created_at: :desc).first
if @response.nil?
@response = Response.create(
map_id: @map.id,
additional_comment: params[:review][:comments],
round: @round.to_i,
is_submitted: is_submitted
)
end
was_submitted = @response.is_submitted
@response.update(additional_comment: params[:review][:comments], is_submitted: is_submitted)
# ignore if autoupdate try to save when the response object is not yet created.
# ,:version_num=>@version)
# Change the order for displaying questions for editing response views.
questions = sort_questions(@questionnaire.questions)
create_answers(params, questions) if params[:responses]
msg = "Your response was successfully saved."
error_msg = ""
# only notify if is_submitted changes from false to true
if (@map.is_a? ReviewResponseMap) && (was_submitted == false && @response.is_submitted) && @response.significant_difference?
@response.notify_instructor_on_difference
@response.email
end
redirect_to controller: 'response', action: 'save', id: @map.map_id,
return: params[:return], msg: msg, error_msg: error_msg, review: params[:review], save_options: params[:save_options]
end
Solution:
The first instance of was_submitted was removed. This variable was renamed to previously_submitted in the other lines of the create method. The purpose of this variable is to determine if the response was previously submitted or the submitted response is a new response. These changes are shown in the code below.
def create
map_id = params[:id]
map_id = params[:map_id] unless params[:map_id].nil? # pass map_id as a hidden field in the review form
@map = ResponseMap.find(map_id)
if params[:review][:questionnaire_id]
@questionnaire = Questionnaire.find(params[:review][:questionnaire_id])
@round = params[:review][:round]
else
@round = nil
end
is_submitted = (params[:isSubmit] == 'Yes')
# There could be multiple responses per round, when re-submission is enabled for that round.
# Hence we need to pick the latest response.
@response = Response.where(map_id: @map.id, round: @round.to_i).order(created_at: :desc).first
if @response.nil?
@response = Response.create(
map_id: @map.id,
additional_comment: params[:review][:comments],
round: @round.to_i,
is_submitted: is_submitted
)
end
previously_submitted = @response.is_submitted
@response.update(additional_comment: params[:review][:comments], is_submitted: is_submitted)
# ignore if autoupdate try to save when the response object is not yet created.
# ,:version_num=>@version)
# Change the order for displaying questions for editing response views.
questions = sort_questions(@questionnaire.questions)
create_answers(params, questions) if params[:responses]
msg = "Your response was successfully saved."
error_msg = ""
# only notify if is_submitted changes from false to true
if (@map.is_a? ReviewResponseMap) && (previously_submitted == false && @response.is_submitted) && @response.significant_difference?
@response.notify_instructor_on_difference
@response.email
end
redirect_to controller: 'response', action: 'save', id: @map.map_id,
return: params[:return], msg: msg, error_msg: error_msg, review: params[:review], save_options: params[:save_options]
end
Task 5
Problem:
The private methods have few to no comments.
Solution:
Comments were added to the private methods as shown below.
# assigning the instance variables for Edit and New actions def assign_instance_vars
# identifying the questionnaire type # updating the current round for the reviewer's responses def set_questionnaire_for_new_response
# maps questions based on their id to its corresponding to its review score def scores
# if user is not filling a new rubric, the @response object should be available. # we can find the questionnaire from the question_id in answers def set_questionnaire
# checks if the questionnaire is nil and opens drop down or rating accordingly def set_dropdown_or_scale
# sorts by sequence number def sort_questions(questions)
def create_answers(params, questions)
# create score if it is not found. If it is found update it otherwise update it.
def init_answers(questions)
questions.each do |q|
# it's unlikely that these answers exist, but in case the user refresh the browser some might have been inserted.
Task 6
Problem:
Redirect method has a if-else ladder. See if it can be refactored to something more understandable.
Originally, the redirect method was :-
def redirect
error_id = params[:error_msg]
message_id = params[:msg]
flash[:error] = error_id unless error_id and error_id.empty?
flash[:note] = message_id unless message_id and message_id.empty?
@map = Response.find_by(map_id: params[:id])
if params[:return] == "feedback"
redirect_to controller: 'grades', action: 'view_my_scores', id: @map.reviewer.id
elsif params[:return] == "teammate"
redirect_to view_student_teams_path student_id: @map.reviewer.id
elsif params[:return] == "instructor"
redirect_to controller: 'grades', action: 'view', id: @map.response_map.assignment.id
elsif params[:return] == "assignment_edit"
redirect_to controller: 'assignments', action: 'edit', id: @map.response_map.assignment.id
elsif params[:return] == "selfreview"
redirect_to controller: 'submitted_content', action: 'edit', id: @map.response_map.reviewer_id
elsif params[:return] == "survey"
redirect_to controller: 'survey_deployment', action: 'pending_surveys'
else
redirect_to controller: 'student_review', action: 'list', id: @map.reviewer.id
end
end
Solution:
A local variable was created to hold the description of the action to be taken by the redirect method. The if-else ladder was transformed into a switch (case) statement to make the code more legible.
The modifications to the redirect method are shown below.
def redirect
error_id = params[:error_msg]
message_id = params[:msg]
flash[:error] = error_id unless error_id and error_id.empty?
flash[:note] = message_id unless message_id and message_id.empty?
@map = Response.find_by(map_id: params[:id])
case params[:return]
when "feedback"
redirect_to controller: 'grades', action: 'view_my_scores', id: @map.reviewer.id
when "teammate"
redirect_to view_student_teams_path student_id: @map.reviewer.id
when "instructor"
redirect_to controller: 'grades', action: 'view', id: @map.response_map.assignment.id
when "assignment_edit"
redirect_to controller: 'assignments', action: 'edit', id: @map.response_map.assignment.id
when "selfreview"
redirect_to controller: 'submitted_content', action: 'edit', id: @map.response_map.reviewer_id
when "survey"
redirect_to controller: 'survey_deployment', action: 'pending_surveys'
else
redirect_to controller: 'student_review', action: 'list', id: @map.reviewer.id
end
end
Test Plan
Because of moving the pending_surveys method, some of the original spec tests failed. So we fixed it.
context 'when params[:return] is survey' do
it 'redirects to survey_deployment#pending_surveys page' do
@params[:return] = 'survey'
get :redirect, @params
expect(response).to redirect_to('/survey_deployment/pending_surveys')
end
end
context 'when params[:return] is other content' do
it 'redirects to student_review#list page' do
@params[:return] = 'other'
get :redirect, @params
expect(response).to redirect_to('/student_review/list?id=1')
end
end
Code Climate and Travis CI
There are only cyclomatic, cognitive errors with code climate whereas there are no integration errors with Travis CI
References
1. The problem statement for E 1907 can be viewed here https://docs.google.com/document/d/1SeIPiccoujhJZgdb3WzWBkg2v8TKSn5SwcHBeX9kzJQ/edit?usp=sharing
2. The pull request for this assignment can be viewed at: https://github.com/expertiza/expertiza/pull/1414
3. Team Branches: All the three team members have contributed towards the project and their branches can be viewed here https://github.com/Anusha-Godavarthi/expertiza/branches
4. Screencast: https://docs.google.com/presentation/d/1AAc95U7vq-zJ8mgD4lVvoQzn5Dui75cMKCoAyjcRm8c/edit?usp=sharing
5. Expertiza Main Repo https://github.com/expertiza/expertiza
6. Expertiza Documentation http://wiki.expertiza.ncsu.edu/index.php/Main_Page
Team Members
1. Anusha Godavarithi
2. Michael Lewallen
3. Akhil Pabba