CSC/ECE 517 Fall 2021 - E2160. Implementing and testing import export controllers

Team

• Akash Sarda, aksarda
• Sairam Sakhamuri, svsakham
• Sidhant Arora, sarora22
• Sai Harsha Nadendla, snadend2

Import and Export Functionality

In Expertiza, many kinds of files can be imported or exported: lists of users for whom accounts are to be created, lists of teams that have been created or need to be created, lists of topics that users are to be able to sign up for, or instructor or peer scores that have been given for a particular assignment. Historically, all of these import and export methods were written individually, using similar code patterns. The instructor might end up adding those in excel or having that data in excel - this functionality allows the expertiza to accept that csv file and tabulate it infront of the user. The user can then select to assign columns to that data and then import it into the database. Eg. list of topics or feedback comments from the students can be tabular if it is say a MCQ questionnaire. The instructor will then have to either enter each entry manually through the UI or can upload this file to automate it.

The export functionality is however is already quite refactored to suit the strategy pattern, which is not changed by the previous group as well.

Problem Description

Initially the different classes (Topics, Assignments, Course Participants) had different implementations of taking in the csv file which was tightly coupled with the feature / model class. However, it was discovered that instead of defining the new method again and again, this process can be automated, by pushing common code of reading the headers and writing to the database into a single generic function. This would basically make it really easy to add this functionality to other model classes and to the new features yet to come to Expertiza.

Existing Import Functionality

The current import functionality is done through the ImportFileController and there are different import class methods implemented in different models that are performing import function.

In the SignUpTopic and User models use helper classes and the attributes are taken from a hash and new ActiveRecord object is created.

Controllers

• import_file_controller, methods:
  • Methods used to process files:
    • #get_delimiter - Sets delimiter for filetype
    • #parse_line - Processes line of the file
    • #parse_to_grid - parses the file into 2D array
    • #parse_to_hash - parses file into hash where 'header' stores header row and 'body' stores all contents.
    • #hash_rows_with_headers - Creates hash for each row of file. Keys are headers, values are row values.
  • Import methods:
    • #import_from_hash - Primary import functionality. Creates objects for hashed rows (from #hash_rows_with_headers).
    • #import - Larger controller of import, sets error messages and displays.

Helpers

• import_file_helper, the list of methods in the file are the following:
  • ::define_attributes - Sets and returns attributes for User object from hash.
  • ::create_new_user - Makes a user object in the database.

• import_topics_helper, the list of methods in the file are the following:
  • ::define_attributes - Sets and returns attributes for a SignUpTopic from hash.
  • ::create_new_sign_up_topic - Makes SignUpTopic objects in the database.

Models

We have found that the below mentioned models are using the import functionality defined in ImportFileController. SignUpTopic and User are dependent on the helper methods to use import functionality.

• assignment_participant
• assignment_team
• course_participant
• course_team
• team
• metareview_response_map
• question
• review_response_map
• sign_up_sheet
• sign_up_topic
• user

Design Plan

The design plan is to use Strategy patter to implement import functionality, so that all the import requests present in different models are routed through the ImportFileController. Right now since the import functionality is implemented in various model methods this leads to many if and else statements to check the type of model. So, we intent to generalize the import functionality by placing common code in the ImportFileController. But each model will still have its own import method. With this approach the redundancy is reduced by moving common code to ImportFileController and code will become DRY.

Other helper methods such as ImportFileHelper and ImportTopicHelper that are used to perform import functionality will also be removed, which keeps import functionality consistent. We will be using method overloading and overriding for the methods in ImportFileController to eliminate unnecessary if and else blocks.

To summarize our plan of changes:

• Redirect all import calls through ImportFileController
• Refactor ImportFileController by removing the redundant code and making code generic.
• Insert object creation conditions into all relevant ::import functions and into the ImportFileController form.

What has been Implemented

Models

• ImportFileController is changed and has been made more generalized, many case statements are removed. The ImprortFileController is made so small and understandable. The import functionality is moved into the corresponding models. Previously code was present in different modules which was confusing now the functionality was all in one place. The following code changes are follows:

• Previous Implmentation

  def import_from_hash(session, params)
    if params[:model] == "AssignmentTeam" or params[:model] == "CourseTeam"
      contents_hash = eval(params[:contents_hash])
      @header_integrated_body = hash_rows_with_headers(contents_hash[:header],contents_hash[:body])
      errors = []
      begin
        @header_integrated_body.each do |row_hash|
          if params[:model] == "AssignmentTeam"
            teamtype = AssignmentTeam
          else
            teamtype = CourseTeam
          end
          options = eval(params[:options])
          options[:has_teamname] = params[:has_teamname]
          Team.import(row_hash, params[:id], options, teamtype)
        end
      rescue
        errors << $ERROR_INFO
      end
      elsif params[:model] == "ReviewResponseMap"
        contents_hash = eval(params[:contents_hash])
        @header_integrated_body = hash_rows_with_headers(contents_hash[:header],contents_hash[:body])
        errors = []
        begin
          @header_integrated_body.each do |row_hash|
            ReviewResponseMap.import(row_hash,session,params[:id])
          end
        rescue
          errors << $ERROR_INFO
        end
    elsif params[:model] == "MetareviewResponseMap"
      contents_hash = eval(params[:contents_hash])
      @header_integrated_body = hash_rows_with_headers(contents_hash[:header],contents_hash[:body])
      errors = []
      begin
        @header_integrated_body.each do |row_hash|
          MetareviewResponseMap.import(row_hash,session,params[:id])
        end
      rescue
        errors << $ERROR_INFO
      end
    elsif params[:model] == 'SignUpTopic' || params[:model] == 'SignUpSheet'
      contents_hash = eval(params[:contents_hash])
      if params[:has_header] == 'true'
        @header_integrated_body = hash_rows_with_headers(contents_hash[:header],contents_hash[:body])
      else
        if params[:optional_count] == '0'
          new_header = [params[:select1], params[:select2], params[:select3]]
          @header_integrated_body = hash_rows_with_headers(new_header,contents_hash[:body])
        elsif params[:optional_count] == '1'
          new_header = [params[:select1], params[:select2], params[:select3], params[:select4]]
          @header_integrated_body = hash_rows_with_headers(new_header,contents_hash[:body])
        elsif params[:optional_count] == '2'
          new_header = [params[:select1], params[:select2], params[:select3], params[:select4], params[:select5]]
          @header_integrated_body = hash_rows_with_headers(new_header,contents_hash[:body])
        elsif params[:optional_count] == '3'
          new_header = [params[:select1], params[:select2], params[:select3], params[:select4], params[:select5], params[:select6]]
          @header_integrated_body = hash_rows_with_headers(new_header,contents_hash[:body])
        end
      end
      errors = []
      begin
        @header_integrated_body.each do |row_hash|
          session[:assignment_id] = params[:id]
          Object.const_get(params[:model]).import(row_hash, session, params[:id])
        end
      rescue
        errors << $ERROR_INFO
      end
    elsif params[:model] == 'AssignmentParticipant' || params[:model] == 'CourseParticipant'
      contents_hash = eval(params[:contents_hash])
      if params[:has_header] == 'true'
        @header_integrated_body = hash_rows_with_headers(contents_hash[:header], contents_hash[:body])
      else
        new_header = [params[:select1], params[:select2], params[:select3], params[:select4]]
        @header_integrated_body = hash_rows_with_headers(new_header, contents_hash[:body])
      end
      errors = []
      begin
        if params[:model] == 'AssignmentParticipant'
          @header_integrated_body.each do |row_hash|
            AssignmentParticipant.import(row_hash, session, params[:id])
          end
        elsif params[:model] == 'CourseParticipant'
          @header_integrated_body.each do |row_hash|
            CourseParticipant.import(row_hash, session, params[:id])
          end
        end
      rescue
        errors << $ERROR_INFO
      end
    else # params[:model] = "User"
      contents_hash = eval(params[:contents_hash])
      if params[:has_header] == 'true'
        @header_integrated_body = hash_rows_with_headers(contents_hash[:header],contents_hash[:body])
      else
        new_header = [params[:select1], params[:select2], params[:select3]]
        @header_integrated_body = hash_rows_with_headers(new_header, contents_hash[:body])
      end
      errors = []
      begin
        @header_integrated_body.each do |row_hash|
          User.import(row_hash, nil, session)
        end
      rescue StandardError
        errors << $ERROR_INFO
      end
  end

• Current Implementation

  def import
    errors = import_from_hash(session, params)
    err_msg = "The following errors were encountered during import.Other records may have been added. A second submission will not duplicate these records."
    errors.each do |error|
      err_msg = err_msg + error.to_s
    end
    err_msg += </ul>
    if errors.empty?
      ExpertizaLogger.info LoggerMessage.new(controller_name, session[:user].name, "The file has been successfully imported.", request)
      undo_link("The file has been successfully imported.")
    else
      ExpertizaLogger.error LoggerMessage.new(controller_name, session[:user].name, err_msg, request)
      flash[:error] = err_msg
    end
    redirect_to session[:return_to]
  end

• Assignment Participant is changed to use the newly implemented #import functionality. Changes are as shown below:

  def self.import(row_hash, session, id)
    raise ArgumentError, "Record does not contain required items." if row_hash.length < self.required_import_fields.length
    user = User.find_by(name: row_hash[:name])
    user = User.import(row_hash, session, nil) if user.nil?
    raise ImportError, "The assignment with id #{id} was not found." if Assignment.find(id).nil?
    unless AssignmentParticipant.exists?(user_id: user.id, parent_id: id)
      new_part = AssignmentParticipant.new(user_id: user.id, parent_id: id)
      new_part.set_handle
    end
  end

  def self.required_import_fields
    {"name" => "Name",
     "fullname" => "Full Name",
     "email" => "Email"}
  end

  def self.optional_import_fields(id=nil)
    {}
  end

  def self.import_options
    {}
  end

• Assignment Team is also changed to use the newly implemented #import functionality.

  def self.import(row_hash, session = nil, id, options)
    raise ArgumentError, "Record does not contain required items." if row_hash.length < self.required_import_fields.length
    raise ImportError, "The assignment with the id \"" + id.to_s + "\" was not found. <a href='/assignment/new'>Create</a> this assignment?" if Assignment.find_by(id: id).nil?
    Team.import_helper(row_hash, id, options, prototype)
  end

  def self.required_import_fields
    {"teammembers" => "Team Members"}
  end

  def self.optional_import_fields(id=nil)
    {"teamname" => "Team Name"}
  end

  def self.import_options
     {"handle_dups" => {"display" => "Handle Duplicates",
                      "options" => {"ignore" => "Ignore new team name",
                                      "replace" => "Replace the existing team with the new team",
                                      "insert" => "Insert any new team members into the existing team",
                                      "rename" => "Rename the new team and import"}}}
  end

• Course_team is is also changed to use the newly implemented #import functionality.

def self.import(row_hash, session, id, options)
      raise ArgumentError, "Record does not contain required items." if row_hash.length < self.required_import_fields.length
      raise ImportError, "The course with the id \"" + id.to_s + "\" was not found. <a href='/course/new'>Create</a> this course?" if Course.find(id).nil?
      Team.import_helper(row_hash, id, options, prototype)
  end

  def self.required_import_fields
      {"teammembers" => "Team Members"}
  end

  def self.optional_import_fields(id=nil)
      {"teamname" => "Team Name"}
  end

  def self.import_options
      {"handle_dups" => {"display" => "Handle Duplicates",
                         "options" => {"ignore" => "Ignore new team name",
                                       "replace" => "Replace the existing team with the new team",
                                       "insert" => "Insert any new team members into the existing team",
                                       "rename" => "Rename the new team and import"}}}
  end

• Review response map's #import functionality is also updated to use the newly implemented #import functionality.

  def self.import(row_hash, _session, assignment_id)
    raise ArgumentError, "Record does not contain required items." if row_hash.length < self.required_import_fields.length
    reviewee_user_name = row_hash[:reviewee].to_s
    reviewee_user = User.find_by(name: reviewee_user_name)
    raise ArgumentError, "Cannot find reviewee user." unless reviewee_user
	@@ -57,7 +58,7 @@ def self.import(row_hash, _session, assignment_id)
      team_node = TeamNode.create(parent_id: assignment_id, node_object_id: reviewee_team.id)
      TeamUserNode.create(parent_id: team_node.id, node_object_id: t_user.id)
    end
    row_hash[:reviewers].split.each do |reviewer|
      reviewer_user_name = reviewer.to_s
      reviewer_user = User.find_by(name: reviewer_user_name)
      raise ArgumentError, "Cannot find reviewer user." unless reviewer_user
	@@ -71,6 +72,20 @@ def self.import(row_hash, _session, assignment_id)
    end
  end

With these new changes to #import functionality. The following modules review_response_map.rb, course_team.rb,assignment_team.rb,assignment_participant.rb have the "self.import" which will use the import functionality in the ImportFileController and they are made as concise as possible. Each module has specific checks while importing the file, so we can't have same code for all the module.

Test Plan

The import method has been implemented in a bunch of models which have been listed above. After preliminary analysis, we assume that the import functionality in a few of the models might have to be amended. These models are:

• assignment_participant
• assignment_team
• course_participant
• course_team
• team
• metareview_response_map
• review_response_map
• sign_up_topic
• user

We will update the test plan for those models in which the import code is amended to fit into the new framework. If we amend the import code in any other model, we will also update the tests in their respective .spec files to ensure 100% coverage. We also plan to create a spec file for the import_file_controller.

Scenarios:

  1. when assignment found and assignment participant does not exist, creates a new user and participant
  2. when assignment cannot be found, creates a new user then raises an ImportError
  3. when the assignment team does not have the required fields, raises ArgumentError
  4. check what import/export actions are allowed for admin, instructor, TA, student
  5. when course found and course participant does not exist, creates a new user and participant
  6. when the course team does not have the required fields, raises ArgumentError