CSC/ECE 517 Spring 2023 - E2301. Refactor review maping helper

Introduction

This page gives a description of the changes made for the review_mapping_helper.rb of Expertiza based OSS project.

Overview of Expertiza

Expertiza is a learning management system that is available as open source software and was created using Ruby on Rails. It has a wide range of features and capabilities, where students can submit and peer-review learning objects (articles, codes, websites, etc). Instructors add and grade the assignments submitted by students to Expertiza. The files that are largely addressed in this project, such as assignment_node.rb, course_node.rb, team_node.rb, folder_node.rb, and questionnaire_node.rb, are essential in executing this functionality. It is supported by the National Science Foundation.

Problem Statement

The review_mapping_helper.rb has multiple functions with a high complexities namely - Cognitive, Perceived, Cyclomatic, Assignment Branch Condition size (ABC size) and Lines of Code (LOC). The review_mapping_helper.rb has methods which exceeds the limit on lines of code. It is missing proper comments for each functionality.

Changes Made

1) Reduced lines of code by removing unnecessary line breaks in display_volume_metric_chart

Before

def display_volume_metric_chart(reviewer)
   labels, reviewer_data, all_reviewers_data = initialize_chart_elements(reviewer)
   data = {
     labels: labels,
     datasets: [
       {
         label: 'vol.',
         backgroundColor: 'rgba(255,99,132,0.8)',
         borderWidth: 1,
         data: reviewer_data,
         yAxisID: 'bar-y-axis1'
       },
       {
         label: 'avg. vol.',
         backgroundColor: 'rgba(255,206,86,0.8)',
         borderWidth: 1,
         data: all_reviewers_data,
         yAxisID: 'bar-y-axis2'
       }
     ]
   }
   options = {
     legend: {
       position: 'top',
       labels: {
         usePointStyle: true
       }
     },
     width: '200',
     height: '125',
     scales: {
       yAxes: [{
         stacked: true,
         id: 'bar-y-axis1',
         barThickness: 10
       }, {
         display: false,
         stacked: true,
         id: 'bar-y-axis2',
         barThickness: 15,
         type: 'category',
         categoryPercentage: 0.8,
         barPercentage: 0.9,
         gridLines: {
           offsetGridLines: true
         }
       }],
       xAxes: [{
         stacked: false,
         ticks: {
           beginAtZero: true,
           stepSize: 50,
           max: 400
         }
       }]
     }
   }
   horizontal_bar_chart data, options
 end

After

def display_volume_metric_chart(reviewer)
   labels, reviewer_data, all_reviewers_data = initialize_chart_elements(reviewer)
   data = {
     labels: labels,
     datasets: [
       {
         label: 'vol.',
         backgroundColor: 'rgba(255,99,132,0.8)',
         borderWidth: 1,
         data: reviewer_data,
         yAxisID: 'bar-y-axis1'
       },
       {
         label: 'avg. vol.',
         backgroundColor: 'rgba(255,206,86,0.8)',
         borderWidth: 1,
         data: all_reviewers_data,
         yAxisID: 'bar-y-axis2'
       }
     ]
   }
   options = {
     legend: { position: 'top', labels: { usePointStyle: true } },
     width: '200', height: '125',
     scales: {
       yAxes: [
         { stacked: true, id: 'bar-y-axis1', barThickness: 10 },
         {
           display: false, stacked: true, id: 'bar-y-axis2',
           barThickness: 15, type: 'category',
           categoryPercentage: 0.8, barPercentage: 0.9,
           gridLines: { offsetGridLines: true }
         }
       ],
       xAxes: [
         { stacked: false, ticks: { beginAtZero: true, stepSize: 50, max: 400 } }
       ]
     }
   }
   horizontal_bar_chart(data, options)
 end

2) Simplified the unless condition by using a single-line unless expression and removing the interval_mean variable initialization outside of it. Used the sum method to calculate the sum of the intervals instead of reduce(:+). Used a single-line conditional operator (!intervals.empty? && ...) to add the "Mean time spent" dataset to the chart, avoiding the need for an unless statement. Removed unnecessary curly braces around single-line hashes

Before

def display_tagging_interval_chart(intervals)
   # if someone did not do any tagging in 30 seconds, then ignore this interval
   threshold = 30
   intervals = intervals.select { |v| v < threshold }
   unless intervals.empty?
     interval_mean = intervals.reduce(:+) / intervals.size.to_f
   end
   # build the parameters for the chart
   data = {
     labels: [*1..intervals.length],
     datasets: [
       {
         backgroundColor: 'rgba(255,99,132,0.8)',
         data: intervals,
         label: 'time intervals'
       },
       unless intervals.empty?
         {
           data: Array.new(intervals.length, interval_mean),
           label: 'Mean time spent'
         }
       end
     ]
   }
   options = {
     width: '200',
     height: '125',
     scales: {
       yAxes: [{
         stacked: false,
         ticks: {
           beginAtZero: true
         }
       }],
       xAxes: [{
         stacked: false
       }]
     }
   }
   line_chart data, options
 end

After

def display_tagging_interval_chart(intervals)
   threshold = 30
   intervals = intervals.select { |v| v < threshold }
   interval_mean = intervals.sum / intervals.size.to_f unless intervals.empty?
   data = {
     labels: [*1..intervals.length],
     datasets: [
       { backgroundColor: 'rgba(255,99,132,0.8)', data: intervals, label: 'time intervals' },
       *(!intervals.empty? && [{ data: [interval_mean] * intervals.length, label: 'Mean time spent' }])
     ]
   }
   options = {
     width: '200', height: '125',
     scales: { yAxes: [{ stacked: false, ticks: { beginAtZero: true } }], xAxes: [{ stacked: false }] }
   }
   line_chart(data, options)
 end