implemented partial batch update for exercises

app/assets/javascripts/exercises.js

@@ -15,11 +15,45 @@ $(function() {
     $('body, html').scrollTo('#add-file');
   };
 
+  var ajaxError = function(response) {
+    $.flash.danger({
+      text: $('#flash').data('message-failure')
+    });
+  };
+
+  var buildCheckboxes = function() {
+    $('tbody tr').each(function(index, element) {
+      var td = $('td.public', element);
+      var checkbox = $('<input>', {
+        checked: td.data('value'),
+        type: 'checkbox'
+      });
+      td.on('click', function(event) {
+        event.preventDefault();
+        checkbox.prop('checked', !checkbox.prop('checked'));
+      });
+      td.html(checkbox);
+    });
+  };
+
   var discardFile = function(event) {
     event.preventDefault();
     $(this).parents('li').remove();
   };
 
+  var enableBatchUpdate = function() {
+    $('thead .batch a').on('click', function(event) {
+      event.preventDefault();
+      if (!$(this).data('toggled')) {
+        $(this).data('toggled', true);
+        $(this).text($(this).data('text'));
+        buildCheckboxes();
+      } else {
+        performBatchUpdate();
+      }
+    });
+  };
+
   var enableInlineFileCreation = function() {
     $('#add-file').on('click', addFileForm);
     $('#files').on('click', 'li .discard-file', discardFile);
@@ -84,6 +118,23 @@ $(function() {
     });
   };
 
+  var performBatchUpdate = function() {
+    var jqxhr = $.ajax({
+      data: {
+        exercises: _.map($('tbody tr'), function(element) {
+          return {
+            id: $(element).data('id'),
+            public: $('.public input', element).prop('checked')
+          };
+        })
+      },
+      dataType: 'json',
+      method: 'PUT'
+    });
+    jqxhr.done(window.CodeOcean.refresh);
+    jqxhr.fail(ajaxError);
+  };
+
   var toggleCodeHeight = function() {
     $('code').on('click', function() {
       $(this).css({
@@ -93,7 +144,9 @@ $(function() {
   };
 
   if ($.isController('exercises')) {
-    if ($('.edit_exercise, .new_exercise').isPresent()) {
+    if ($('table').isPresent()) {
+      enableBatchUpdate();
+    } else if ($('.edit_exercise, .new_exercise').isPresent()) {
       execution_environments = $('form').data('execution-environments');
       file_types = $('form').data('file-types');
       new MarkdownEditor('#exercise_instructions');

app/controllers/exercises_controller.rb

@@ -15,6 +15,17 @@ class ExercisesController < ApplicationController
   end
   private :authorize!
 
+  def batch_update
+    @exercises = Exercise.all
+    authorize!
+    @exercises = params[:exercises].values.map do |exercise_params|
+      exercise = Exercise.find(exercise_params.delete(:id))
+      exercise.update(exercise_params)
+      exercise
+    end
+    render(json: {exercises: @exercises})
+  end
+
   def clone
     exercise = @exercise.duplicate(public: false, token: nil, user: current_user)
     exercise.send(:generate_token)

app/policies/exercise_policy.rb

@@ -4,6 +4,10 @@ class ExercisePolicy < AdminOrAuthorPolicy
   end
   private :author?
 
+  def batch_update?
+    admin?
+  end
+
   [:clone?, :destroy?, :edit?, :show?, :statistics?, :update?].each do |action|
     define_method(action) { admin? || author? || team_member? }
   end

app/views/exercises/index.html.slim

@@ -17,17 +17,21 @@ h1 = Exercise.model_name.human(count: 2)
         th = sort_link(@search, :execution_environment_id, t('activerecord.attributes.exercise.execution_environment'))
         th = t('.test_files')
         th = t('activerecord.attributes.exercise.maximum_score')
-        th = t('activerecord.attributes.exercise.public')
+        th
+          = t('activerecord.attributes.exercise.public')
+          - if policy(Exercise).batch_update?
+            br
+            span.batch = link_to(t('shared.batch_update'), '#', 'data-text' => t('shared.update', model: t('activerecord.models.exercise.other')))
         th colspan=6 = t('shared.actions')
     tbody
       - @exercises.each do |exercise|
-        tr
+        tr data-id=exercise.id
           td = exercise.title
           td = link_to(exercise.author, exercise.author)
           td = link_to(exercise.execution_environment, exercise.execution_environment)
           td = exercise.files.teacher_defined_tests.count
           td = exercise.maximum_score
-          td = symbol_for(exercise.public?)
+          td.public data-value=exercise.public? = symbol_for(exercise.public?)
           td = link_to(t('shared.show'), exercise)
           td = link_to(t('shared.edit'), edit_exercise_path(exercise))
           td = link_to(t('shared.destroy'), exercise, data: {confirm: t('shared.confirm_destroy')}, method: :delete)