Merge branch 'MDL-69559-master-7' of git://github.com/mickhawkins/moodle

admin/settings/courses.php

@@ -22,6 +22,8 @@
  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+use core_admin\local\settings\filesize;
+
 $capabilities = array(
     'moodle/backup:backupcourse',
     'moodle/category:manage',
@@ -75,6 +77,17 @@ if ($hassiteconfig or has_any_capability($capabilities, $systemcontext)) {
     $temp->add(new admin_setting_configselect('moodlecourse/visible', new lang_string('visible'), new lang_string('visible_help'),
         1, $choices));
 
+    // Enable/disable download course content.
+    $choices = [
+        DOWNLOAD_COURSE_CONTENT_DISABLED => new lang_string('no'),
+        DOWNLOAD_COURSE_CONTENT_ENABLED => new lang_string('yes'),
+    ];
+    $downloadcontentsitedefault = new admin_setting_configselect('moodlecourse/downloadcontentsitedefault',
+            new lang_string('enabledownloadcoursecontent', 'course'),
+            new lang_string('downloadcoursecontent_help', 'course'), 0, $choices);
+    $downloadcontentsitedefault->add_dependent_on('downloadcoursecontentallowed');
+    $temp->add($downloadcontentsitedefault);
+
     // Course format.
     $temp->add(new admin_setting_heading('courseformathdr', new lang_string('type_format', 'plugin'), ''));
 
@@ -161,6 +174,21 @@ if ($hassiteconfig or has_any_capability($capabilities, $systemcontext)) {
 
     $ADMIN->add('courses', $temp);
 
+    // Download course content.
+    $downloadcoursedefaulturl = new moodle_url('/admin/settings.php', ['section' => 'coursesettings']);
+    $temp = new admin_settingpage('downloadcoursecontent', new lang_string('downloadcoursecontent', 'course'));
+    $temp->add(new admin_setting_configcheckbox('downloadcoursecontentallowed',
+            new lang_string('downloadcoursecontentallowed', 'admin'),
+            new lang_string('downloadcoursecontentallowed_desc', 'admin', $downloadcoursedefaulturl->out()), 0));
+
+    // 50MB default maximum size per file when downloading course content.
+    $defaultmaxdownloadsize = 50 * filesize::UNIT_MB;
+    $temp->add(new filesize('maxsizeperdownloadcoursefile', new lang_string('maxsizeperdownloadcoursefile', 'admin'),
+            new lang_string('maxsizeperdownloadcoursefile_desc', 'admin'), $defaultmaxdownloadsize, filesize::UNIT_MB));
+    $temp->hide_if('maxsizeperdownloadcoursefile', 'downloadcoursecontentallowed');
+
+    $ADMIN->add('courses', $temp);
+
     // "courserequests" settingpage.
     $temp = new admin_settingpage('courserequest', new lang_string('courserequest'));
     $temp->add(new admin_setting_configcheckbox('enablecourserequests',

course/amd/build/downloadcontent.min.js

@@ -0,0 +1,2 @@
+function _typeof(a){"@babel/helpers - typeof";if("function"==typeof Symbol&&"symbol"==typeof Symbol.iterator){_typeof=function(a){return typeof a}}else{_typeof=function(a){return a&&"function"==typeof Symbol&&a.constructor===Symbol&&a!==Symbol.prototype?"symbol":typeof a}}return _typeof(a)}define ("core_course/downloadcontent",["exports","core/config","core/custom_interaction_events","core/modal_factory","jquery","core/pending"],function(a,b,c,d,e,f){"use strict";Object.defineProperty(a,"__esModule",{value:!0});a.init=void 0;b=i(b);c=i(c);d=h(d);e=i(e);f=i(f);function g(){if("function"!=typeof WeakMap)return null;var a=new WeakMap;g=function(){return a};return a}function h(a){if(a&&a.__esModule){return a}if(null===a||"object"!==_typeof(a)&&"function"!=typeof a){return{default:a}}var b=g();if(b&&b.has(a)){return b.get(a)}var c={},d=Object.defineProperty&&Object.getOwnPropertyDescriptor;for(var e in a){if(Object.prototype.hasOwnProperty.call(a,e)){var f=d?Object.getOwnPropertyDescriptor(a,e):null;if(f&&(f.get||f.set)){Object.defineProperty(c,e,f)}else{c[e]=a[e]}}}c.default=a;if(b){b.set(a,c)}return c}function i(a){return a&&a.__esModule?a:{default:a}}var j=function(){var a=new f.default;document.addEventListener("click",function(a){var b=a.target.closest("[data-downloadcourse]");if(b){a.preventDefault();k(b)}});a.resolve()};a.init=j;var k=function(a){d.create({title:a.dataset.downloadTitle,type:d.types.SAVE_CANCEL,body:"<p>".concat(a.dataset.downloadBody,"</p>"),buttons:{save:a.dataset.downloadButtonText},templateContext:{classes:"downloadcoursecontentmodal"}}).then(function(b){b.show();var d=document.querySelector(".modal .downloadcoursecontentmodal [data-action=\"save\"]"),f=document.querySelector(".modal .downloadcoursecontentmodal [data-action=\"cancel\"]"),g=document.querySelector(".modal[data-region=\"modal-container\"]");(0,e.default)(d).on(c.default.events.activate,function(c){return l(c,a,b)});(0,e.default)(f).on(c.default.events.activate,function(){b.destroy()});if(g.querySelector(".downloadcoursecontentmodal")){(0,e.default)(g).on(c.default.events.activate,function(){b.destroy()})}})},l=function(a,c,d){a.preventDefault();var e=document.createElement("form");e.action=c.dataset.downloadLink;e.method="POST";e.target="_blank";var f=document.createElement("input");f.name="sesskey";f.value=b.default.sesskey;e.appendChild(f);e.style.display="none";document.body.appendChild(e);e.submit();document.body.removeChild(e);d.destroy()}});
+//# sourceMappingURL=downloadcontent.min.js.map

course/amd/src/downloadcontent.js

@@ -0,0 +1,125 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Functions related to downloading course content.
+ *
+ * @module     core_course/downloadcontent
+ * @package    core_course
+ * @copyright  2020 Michael Hawkins <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+import Config from 'core/config';
+import CustomEvents from 'core/custom_interaction_events';
+import * as ModalFactory from 'core/modal_factory';
+import jQuery from 'jquery';
+import Pending from 'core/pending';
+
+/**
+ * Set up listener to trigger the download course content modal.
+ *
+ * @return {void}
+ */
+export const init = () => {
+    const pendingPromise = new Pending();
+
+    document.addEventListener('click', (e) => {
+        const downloadModalTrigger = e.target.closest('[data-downloadcourse]');
+
+        if (downloadModalTrigger) {
+            e.preventDefault();
+            displayDownloadConfirmation(downloadModalTrigger);
+        }
+    });
+
+    pendingPromise.resolve();
+};
+
+/**
+ * Display the download course content modal.
+ *
+ * @method displayDownloadConfirmation
+ * @param {Object} downloadModalTrigger The DOM element that triggered the download modal.
+ * @return {void}
+ */
+const displayDownloadConfirmation = (downloadModalTrigger) => {
+    ModalFactory.create({
+        title: downloadModalTrigger.dataset.downloadTitle,
+        type: ModalFactory.types.SAVE_CANCEL,
+        body: `<p>${downloadModalTrigger.dataset.downloadBody}</p>`,
+        buttons: {
+            save: downloadModalTrigger.dataset.downloadButtonText
+        },
+        templateContext: {
+            classes: 'downloadcoursecontentmodal'
+        }
+    })
+    .then(modal => {
+        // Display the modal.
+        modal.show();
+
+        const saveButton = document.querySelector('.modal .downloadcoursecontentmodal [data-action="save"]');
+        const cancelButton = document.querySelector('.modal .downloadcoursecontentmodal [data-action="cancel"]');
+        const modalContainer = document.querySelector('.modal[data-region="modal-container"]');
+
+        // Create listener to trigger the download when the "Download" button is pressed.
+        jQuery(saveButton).on(CustomEvents.events.activate, (e) => downloadContent(e, downloadModalTrigger, modal));
+
+        // Create listener to destroy the modal when closing modal by cancelling.
+        jQuery(cancelButton).on(CustomEvents.events.activate, () => {
+            modal.destroy();
+        });
+
+        // Create listener to destroy the modal when closing modal by clicking outside of it.
+        if (modalContainer.querySelector('.downloadcoursecontentmodal')) {
+            jQuery(modalContainer).on(CustomEvents.events.activate, () => {
+                modal.destroy();
+            });
+        }
+    });
+};
+
+/**
+ * Trigger downloading of course content.
+ *
+ * @method downloadContent
+ * @param {Event} e The event triggering the download.
+ * @param {Object} downloadModalTrigger The DOM element that triggered the download modal.
+ * @param {Object} modal The modal object.
+ * @return {void}
+ */
+const downloadContent = (e, downloadModalTrigger, modal) => {
+    e.preventDefault();
+
+    // Create a form to submit the file download request, so we can avoid sending sesskey over GET.
+    const downloadForm = document.createElement('form');
+    downloadForm.action = downloadModalTrigger.dataset.downloadLink;
+    downloadForm.method = 'POST';
+    // Open download in a new tab, so current course view is not disrupted.
+    downloadForm.target = '_blank';
+    const downloadSesskey = document.createElement('input');
+    downloadSesskey.name = 'sesskey';
+    downloadSesskey.value = Config.sesskey;
+    downloadForm.appendChild(downloadSesskey);
+    downloadForm.style.display = 'none';
+
+    document.body.appendChild(downloadForm);
+    downloadForm.submit();
+    document.body.removeChild(downloadForm);
+
+    // Destroy the modal to prevent duplicates if reopened later.
+    modal.destroy();
+};

course/classes/output/content_export_link.php

@@ -0,0 +1,60 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Prepares content for buttons/links to course content export/download.
+ *
+ * @package   core_course
+ * @copyright 2020 Michael Hawkins <[email protected]>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_course\output;
+
+/**
+ * Prepares content for buttons/links to course content export/download.
+ *
+ * @package   core_course
+ * @copyright 2020 Michael Hawkins <[email protected]>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class content_export_link {
+
+    /**
+     * Prepare and return the various attributes required for a link/button to populate/trigger the download course content modal.
+     *
+     * @param \context $context The context of the content being exported.
+     * @return stdClass
+     */
+    public static function get_attributes(\context $context): \stdClass {
+        global $CFG;
+        $downloadattr = new \stdClass();
+        $downloadattr->url = new \moodle_url('/course/downloadcontent.php', ['contextid' => $context->id]);
+        $downloadattr->displaystring = get_string('downloadcoursecontent', 'course');
+        $maxfilesize = display_size($CFG->maxsizeperdownloadcoursefile);
+        $downloadlink = new \moodle_url('/course/downloadcontent.php', ['contextid' => $context->id, 'download' => 1]);
+
+        $downloadattr->elementattributes = [
+            'data-downloadcourse' => 1,
+            'data-download-body' => get_string('downloadcourseconfirmation', 'course', $maxfilesize),
+            'data-download-button-text' => get_string('download'),
+            'data-download-link' => $downloadlink->out(false),
+            'data-download-title' => get_string('downloadcoursecontent', 'course'),
+        ];
+
+        return $downloadattr;
+    }
+}

course/downloadcontent.php

@@ -0,0 +1,94 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Download course content confirmation and execution.
+ *
+ * @package    core
+ * @subpackage course
+ * @copyright  2020 Michael Hawkins <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+require_once('../config.php');
+
+use core\content;
+use core\content\export\zipwriter;
+
+$contextid = required_param('contextid', PARAM_INT);
+$isdownload = optional_param('download', 0, PARAM_BOOL);
+$coursecontext = context::instance_by_id($contextid);
+$courseid = $coursecontext->instanceid;
+$courselink = new moodle_url('/course/view.php', ['id' => $courseid]);
+
+if (!\core\content::can_export_context($coursecontext, $USER)) {
+    redirect($courselink);
+}
+
+$PAGE->set_url('/course/downloadcontent.php', ['contextid' => $contextid]);
+require_login($courseid);
+
+$courseinfo = get_fast_modinfo($courseid)->get_course();
+$filename = str_replace('/', '', str_replace(' ', '_', $courseinfo->shortname)) . '_' . time() . '.zip';
+
+// If download confirmed, prepare and start the zipstream of the course download content.
+if ($isdownload) {
+    confirm_sesskey();
+
+    $exportoptions = null;
+
+    if (!empty($CFG->maxsizeperdownloadcoursefile)) {
+        $exportoptions = new stdClass();
+        $exportoptions->maxfilesize = $CFG->maxsizeperdownloadcoursefile;
+    }
+
+    // Use file writer in debug developer mode, so any errors can be displayed instead of being streamed into the output file.
+    if (debugging('', DEBUG_DEVELOPER)) {
+        $writer = zipwriter::get_file_writer($filename, $exportoptions);
+
+        ob_start();
+        content::export_context($coursecontext, $USER, $writer);
+        $content = ob_get_clean();
+
+        // If no errors found, output the file.
+        if (empty($content)) {
+            send_file($writer->get_file_path(), $filename);
+            redirect($courselink);
+        } else {
+            // If any errors occurred, display them instead of outputting the file.
+            debugging("Errors found while producing the download course content output:\n {$content}", DEBUG_DEVELOPER);
+        }
+    } else {
+        // If not developer debugging, stream the output file directly.
+        $writer = zipwriter::get_stream_writer($filename, $exportoptions);
+        content::export_context($coursecontext, $USER, $writer);
+
+        redirect($courselink);
+    }
+
+} else {
+    $PAGE->set_title(get_string('downloadcoursecontent', 'course'));
+    $PAGE->set_heading(format_string($courseinfo->fullname));
+
+    echo $OUTPUT->header();
+    echo $OUTPUT->heading(get_string('downloadcoursecontent', 'course'));
+
+    // Prepare download confirmation information and display it.
+    $maxfilesize = display_size($CFG->maxsizeperdownloadcoursefile);
+    $downloadlink = new moodle_url('/course/downloadcontent.php', ['contextid' => $contextid, 'download' => 1]);
+
+    echo $OUTPUT->confirm(get_string('downloadcourseconfirmation', 'course', $maxfilesize), $downloadlink, $courselink);
+}

course/edit_form.php

@@ -120,6 +120,27 @@ class course_edit_form extends moodleform {
                 $mform->setConstant('visible', $courseconfig->visible);
             }
         }
+
+        // Download course content.
+        if ($CFG->downloadcoursecontentallowed) {
+            $downloadchoices = [
+                DOWNLOAD_COURSE_CONTENT_DISABLED => get_string('no'),
+                DOWNLOAD_COURSE_CONTENT_ENABLED => get_string('yes'),
+            ];
+            $sitedefaultstring = $downloadchoices[$courseconfig->downloadcontentsitedefault];
+            $downloadchoices[DOWNLOAD_COURSE_CONTENT_SITE_DEFAULT] = get_string('sitedefaultspecified', '', $sitedefaultstring);
+            $downloadselectdefault = $courseconfig->downloadcontent ?? DOWNLOAD_COURSE_CONTENT_SITE_DEFAULT;
+
+            $mform->addElement('select', 'downloadcontent', get_string('enabledownloadcoursecontent', 'course'), $downloadchoices);
+            $mform->addHelpButton('downloadcontent', 'downloadcoursecontent', 'course');
+            $mform->setDefault('downloadcontent', $downloadselectdefault);
+
+            if (!has_capability('moodle/course:configuredownloadcontent', $coursecontext)) {
+                $mform->hardFreeze('downloadcontent');
+                $mform->setConstant('downloadcontent', $downloadselectdefault);
+            }
+        }
+
         $mform->addElement('date_time_selector', 'startdate', get_string('startdate'));
         $mform->addHelpButton('startdate', 'startdate');
         $date = (new DateTime())->setTimestamp(usergetmidnight(time()));

course/lib.php

@@ -71,6 +71,11 @@ define('COURSE_CUSTOMFIELD_EMPTY', -1);
 // Course activity chooser footer default display option.
 define('COURSE_CHOOSER_FOOTER_NONE', 'hidden');
 
+// Download course content options.
+define('DOWNLOAD_COURSE_CONTENT_DISABLED', 0);
+define('DOWNLOAD_COURSE_CONTENT_ENABLED', 1);
+define('DOWNLOAD_COURSE_CONTENT_SITE_DEFAULT', 2);
+
 function make_log_url($module, $url) {
     switch ($module) {
         case 'course':

course/tests/behat/course_download_content.feature

@@ -0,0 +1,47 @@
+@core @core_course
+Feature: Course content can be downloaded
+  In order to retain a backup offline copy of course activity/resource data
+  As a user
+  I can download a course's content
+
+  Background:
+    Given the following "users" exist:
+      | username | firstname | lastname | email                |
+      | teacher1 | Teacher   | 1        | teacher1@example.com |
+      | student1 | Student   | 1        | student1@example.com |
+    And the following "courses" exist:
+      | fullname   | shortname |
+      | Hockey 101 | C1        |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+      | student1 | C1     | student        |
+    And I log in as "admin"
+    And I navigate to "Courses > Courses > Download course content" in site administration
+    And I set the following fields to these values:
+    | Download course content feature available | 1 |
+    And I press "Save changes"
+    And I navigate to "Courses > Courses > Course default settings" in site administration
+    And I set the field "Enable download course content" to "Yes"
+    And I press "Save changes"
+    And I log out
+
+  @javascript
+  Scenario: A student can download course content when the feature is enabled in their course
+  Given I log in as "student1"
+  When I am on "Hockey 101" course homepage
+  And "Download course content" "button" should exist
+  And I press "Download course content"
+  Then I should see "You are about to download a zip file"
+  # Without the ability to check the downloaded file, the absence of an exception being thrown here is considered a success.
+  And I click on "Download" "button" in the "Download course content" "dialogue"
+
+  @javascript
+  Scenario: A teacher can download course content when the feature is enabled in their course
+  Given I log in as "teacher1"
+  When I am on "Hockey 101" course homepage
+  And "Download course content" "link" should exist in current page administration
+  And I navigate to "Download course content" in current page administration
+  Then I should see "You are about to download a zip file"
+  # Without the ability to check the downloaded file, the absence of an exception being thrown here is considered a success.
+  And I click on "Download" "button" in the "Download course content" "dialogue"

course/tests/behat/course_download_content_permissions.feature

@@ -0,0 +1,112 @@
+@core @core_course
+Feature: Access to downloading course content can be controlled
+  In order to allow or restrict access to download course content
+  As a trusted user
+  I can control access to the download course content feature
+
+  Background:
+    Given the following "users" exist:
+      | username | firstname | lastname | email                |
+      | teacher1 | Teacher   | 1        | teacher1@example.com |
+      | student1 | Student   | 1        | student1@example.com |
+    And the following "courses" exist:
+      | fullname   | shortname |
+      | Hockey 101 | C1        |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+      | student1 | C1     | student        |
+    And I log in as "admin"
+    And the following config values are set as admin:
+    | downloadcoursecontentallowed | 1 |
+    And I log out
+
+Scenario: Site admins can remove the download course content feature
+  Given I log in as "admin"
+  And I am on "Hockey 101" course homepage
+  And I navigate to "Edit settings" in current page administration
+  And I set the field "Enable download course content" to "Yes"
+  And I press "Save and display"
+  And "Download course content" "link" should exist in current page administration
+  When the following config values are set as admin:
+    | downloadcoursecontentallowed | 0 |
+  And I am on "Hockey 101" course homepage
+  Then "Download course content" "link" should not exist in current page administration
+  And I navigate to "Edit settings" in current page administration
+  And I should not see "Enable download course content"
+
+Scenario: Site admins can set the default value for whether download course content is enabled in courses
+  Given I log in as "admin"
+  And I am on "Hockey 101" course homepage
+  And "Download course content" "link" should not exist in current page administration
+  When I navigate to "Courses > Courses > Course default settings" in site administration
+  And I set the field "Enable download course content" to "Yes"
+  And I press "Save changes"
+  And I am on "Hockey 101" course homepage
+  Then "Download course content" "link" should exist in current page administration
+
+Scenario: A teacher can enable and disable the download course content feature when it is available
+  Given I log in as "teacher1"
+  When I am on "Hockey 101" course homepage
+  And "Download course content" "link" should not exist in current page administration
+  And I navigate to "Edit settings" in current page administration
+  And I should see "Enable download course content"
+  And I set the field "Enable download course content" to "Yes"
+  And I press "Save and display"
+  Then "Download course content" "link" should exist in current page administration
+  And I navigate to "Edit settings" in current page administration
+  And I set the field "Enable download course content" to "No"
+  And I press "Save and display"
+  And "Download course content" "link" should not exist in current page administration
+
+Scenario: Teachers require a capability to access the download course content feature or modify its availability in a course
+  Given I log in as "admin"
+  And I navigate to "Courses > Courses > Course default settings" in site administration
+  And I set the field "Enable download course content" to "Yes"
+  And I press "Save changes"
+  And I log out
+  # Check teacher can see download option and enable dropdown.
+  And I log in as "teacher1"
+  And I am on "Hockey 101" course homepage
+  And "Download course content" "link" should exist in current page administration
+  And I navigate to "Edit settings" in current page administration
+  And "Enable download course content" "select" should exist
+  And I log out
+  # Remove teacher's capabilities for download course content.
+  And I log in as "admin"
+  And I set the following system permissions of "Teacher" role:
+    | capability                             | permission |
+    | moodle/course:downloadcoursecontent    | Prohibit   |
+    | moodle/course:configuredownloadcontent | Prohibit   |
+  And I log out
+  # Check teacher can no longer see download option, and that enable value is visible, but dropdown no longer available.
+  When I log in as "teacher1"
+  And I am on "Hockey 101" course homepage
+  Then "Download course content" "link" should not exist in current page administration
+  And I navigate to "Edit settings" in current page administration
+  And I should see "Enable download course content"
+  And I should see "Site default (Yes)"
+  And "Enable download course content" "select" should not exist
+
+Scenario: Students require a capability to access the download course content feature in a course
+  Given I log in as "teacher1"
+  And I am on "Hockey 101" course homepage
+  And I navigate to "Edit settings" in current page administration
+  And I set the field "Enable download course content" to "Yes"
+  And I press "Save and display"
+  And I log out
+  # Check student can see download button.
+  And I log in as "student1"
+  And I am on "Hockey 101" course homepage
+  And "Download course content" "button" should exist
+  And I log out
+  And I log in as "admin"
+  # Remove student's capability for download course content.
+  When I set the following system permissions of "Student" role:
+    | capability                             | permission |
+    | moodle/course:downloadcoursecontent    | Prohibit   |
+  And I log out
+  # Check student can no longer see download button.
+  And I log in as "student1"
+  And I am on "Hockey 101" course homepage
+  Then "Download course content" "link" should not exist in current page administration

course/view.php

@@ -223,12 +223,21 @@
         $PAGE->requires->js_init_call('M.core_completion.init');
     }
 
+    // Determine whether the user has permission to download course content.
+    $candownloadcourse = \core\content::can_export_context($context, $USER);
+
     // We are currently keeping the button here from 1.x to help new teachers figure out
     // what to do, even though the link also appears in the course admin block.  It also
     // means you can back out of a situation where you removed the admin block. :)
     if ($PAGE->user_allowed_editing()) {
         $buttons = $OUTPUT->edit_button($PAGE->url);
         $PAGE->set_button($buttons);
+    } else if ($candownloadcourse) {
+        // Show the download course content button if user has permission to access it.
+        // Only showing this if user doesn't have edit rights, since those who do will access it via the actions menu.
+        $buttonattr = \core_course\output\content_export_link::get_attributes($context);
+        $button = new single_button($buttonattr->url, $buttonattr->displaystring, 'post', false, $buttonattr->elementattributes);
+        $PAGE->set_button($OUTPUT->render($button));
     }
 
     // If viewing a section, make the title more specific
@@ -300,4 +309,9 @@
     // Include course AJAX
     include_course_ajax($course, $modnamesused);
 
+    // If available, include the JS to prepare the download course content modal.
+    if ($candownloadcourse) {
+        $PAGE->requires->js_call_amd('core_course/downloadcontent', 'init');
+    }
+
     echo $OUTPUT->footer();

lang/en/admin.php

@@ -516,6 +516,8 @@ $string['doctonewwindow'] = 'Open in new window';
 $string['doesnotfit'] = 'Email display settings';
 $string['doesnotfitdetail'] = 'Display settings for email leaving Moodle.';
 $string['download'] = 'Download';
+$string['downloadcoursecontentallowed'] = 'Download course content feature available';
+$string['downloadcoursecontentallowed_desc'] = 'Whether the download course content feature is available to courses. When available, course content downloads can be enabled/disabled using the "Enable download course content" setting within the course edit menu (the default for this can be set in <a href={$a} target="_blank">Course default settings</a>).';
 $string['durationunits'] = 'duration units';
 $string['edithelpdocs'] = 'Edit help documents';
 $string['editlang'] = '<b>Edit</b>';
@@ -802,6 +804,8 @@ sites. If this is not what you wanted then you should make sure you are updating
 from a STABLE branch of the Moodle code. See Moodle Docs for more details.';
 $string['maxbytes'] = 'Maximum uploaded file size';
 $string['maxconsecutiveidentchars'] = 'Consecutive identical characters';
+$string['maxsizeperdownloadcoursefile'] = 'Maximum size per file';
+$string['maxsizeperdownloadcoursefile_desc'] = 'The maximum size of each file when downloading course content. Files exceeding this size will be omitted from the download.';
 $string['maxeditingtime'] = 'Maximum time to edit posts';
 $string['maxusersperpage'] = ' Maximum users per page';
 $string['configmaxusersperpage'] = 'Maximum number of users displayed within user selector in course, group, cohort, webservice etc.';

lang/en/course.php

@@ -54,6 +54,10 @@ $string['customfield_visibility_help'] = 'This setting determines who can view t
 $string['customfield_visibletoall'] = 'Everyone';
 $string['customfield_visibletoteachers'] = 'Teachers';
 $string['customfieldsettings'] = 'Common course custom fields settings';
+$string['downloadcourseconfirmation'] = 'You are about to download a zip file of course content (excluding items which cannot be downloaded and any files larger than {$a}).';
+$string['downloadcoursecontent'] = 'Download course content';
+$string['downloadcoursecontent_help'] = 'This setting determines whether course content may be downloaded by users with the download course content capability (by default users with the role of student or teacher).';
+$string['enabledownloadcoursecontent'] = 'Enable download course content';
 $string['errorendbeforestart'] = 'The end date ({$a}) is before the course start date.';
 $string['favourite'] = 'Starred course';
 $string['gradetopassnotset'] = 'This course does not have a grade to pass set. It may be set in the grade item of the course (Gradebook setup).';

lang/en/moodle.php

@@ -1930,6 +1930,7 @@ $string['since'] = 'Since';
 $string['sincelast'] = 'since last login';
 $string['site'] = 'Site';
 $string['sitedefault'] = 'Site default';
+$string['sitedefaultspecified'] = 'Site default ({$a})';
 $string['siteerrors'] = 'Site errors';
 $string['sitefiles'] = 'Site files';
 $string['sitefilesused'] = 'Site files used in this course';

lang/en/role.php

@@ -172,6 +172,8 @@ $string['course:changelockedcustomfields'] = 'Change locked custom fields';
 $string['course:changeshortname'] = 'Change course short name';
 $string['course:changesummary'] = 'Change course summary';
 $string['course:configurecustomfields'] = 'Configure custom fields';
+$string['course:configuredownloadcontent'] = 'Configure download course content';
+$string['course:downloadcoursecontent'] = 'Download course content';
 $string['course:enrolconfig'] = 'Configure enrol instances in courses';
 $string['course:enrolreview'] = 'Review course enrolments';
 $string['course:setforcedlanguage'] = 'Force course language';

lib/classes/content.php

@@ -52,7 +52,30 @@ class content {
      * @return  bool
      */
     public static function can_export_context(context $currentcontext, stdClass $user): bool {
-        return true;
+        global $CFG;
+
+        $canexport = false;
+
+        if ($currentcontext->contextlevel == CONTEXT_COURSE) {
+            if ($CFG->downloadcoursecontentallowed &&
+                    has_capability('moodle/course:downloadcoursecontent', $currentcontext, $user)) {
+
+                $courseinfo = get_fast_modinfo($currentcontext->instanceid)->get_course();
+
+                // If enabled/disabled explicitly set on course, use that as the course setting, otherwise use site default.
+                if (isset($courseinfo->downloadcontent) && $courseinfo->downloadcontent != DOWNLOAD_COURSE_CONTENT_SITE_DEFAULT) {
+                    $canexport = $courseinfo->downloadcontent;
+                } else {
+                    $canexport = get_config('moodlecourse')->downloadcontentsitedefault;
+                }
+
+            }
+        } else if ($currentcontext->contextlevel == CONTEXT_MODULE) {
+            // Modules can only be exported if exporting is allowed in their course context.
+            $canexport = self::can_export_context($currentcontext->get_course_context(), $user);
+        }
+
+        return $canexport;
     }
 
     /**

lib/db/access.php

@@ -2576,4 +2576,26 @@ $capabilities = array(
             'editingteacher' => CAP_ALLOW,
         ]
     ],
+
+    // Allow users to download course content.
+    'moodle/course:downloadcoursecontent' => [
+        'captype' => 'read',
+        'contextlevel' => CONTEXT_COURSE,
+        'archetypes' => array(
+            'student' => CAP_ALLOW,
+            'teacher' => CAP_ALLOW,
+            'editingteacher' => CAP_ALLOW,
+            'manager' => CAP_ALLOW
+        )
+    ],
+
+    // Allow users to configure download course content functionality within a course, if the feature is available.
+    'moodle/course:configuredownloadcontent' => [
+        'captype' => 'write',
+        'contextlevel' => CONTEXT_COURSE,
+        'archetypes' => array(
+            'editingteacher' => CAP_ALLOW,
+            'manager' => CAP_ALLOW
+        )
+    ],
 );

lib/db/install.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8" ?>
-<XMLDB PATH="lib/db" VERSION="20201007" COMMENT="XMLDB file for core Moodle tables"
+<XMLDB PATH="lib/db" VERSION="20201021" COMMENT="XMLDB file for core Moodle tables"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:noNamespaceSchemaLocation="../../lib/xmldb/xmldb.xsd"
 >
@@ -89,6 +89,7 @@
         <FIELD NAME="showreports" TYPE="int" LENGTH="4" NOTNULL="true" DEFAULT="0" SEQUENCE="false"/>
         <FIELD NAME="visible" TYPE="int" LENGTH="1" NOTNULL="true" DEFAULT="1" SEQUENCE="false"/>
         <FIELD NAME="visibleold" TYPE="int" LENGTH="1" NOTNULL="true" DEFAULT="1" SEQUENCE="false" COMMENT="the state of visible field when hiding parent category, this helps us to recover hidden states when unhiding the parent category later"/>
+        <FIELD NAME="downloadcontent" TYPE="int" LENGTH="1" NOTNULL="false" SEQUENCE="false"/>
         <FIELD NAME="groupmode" TYPE="int" LENGTH="4" NOTNULL="true" DEFAULT="0" SEQUENCE="false"/>
         <FIELD NAME="groupmodeforce" TYPE="int" LENGTH="4" NOTNULL="true" DEFAULT="0" SEQUENCE="false"/>
         <FIELD NAME="defaultgroupingid" TYPE="int" LENGTH="10" NOTNULL="true" DEFAULT="0" SEQUENCE="false" COMMENT="default grouping used in course modules, does not have key intentionally"/>
@@ -4322,4 +4323,4 @@
       </INDEXES>
     </TABLE>
   </TABLES>
-</XMLDB>
+</XMLDB>

lib/db/upgrade.php

@@ -2774,6 +2774,7 @@ function xmldb_main_upgrade($oldversion) {
 
         // Add example field.
         $field = new xmldb_field('example', XMLDB_TYPE_TEXT, null, null, null, null, null, 'tutorial');
+
         if (!$dbman->field_exists($table, $field)) {
             $dbman->add_field($table, $field);
         }
@@ -2862,5 +2863,18 @@ function xmldb_main_upgrade($oldversion) {
         upgrade_main_savepoint(true, 2021052500.30);
     }
 
+    if ($oldversion < 2021052500.32) {
+        // Define field downloadcontent to be added to course.
+        $table = new xmldb_table('course');
+        $field = new xmldb_field('downloadcontent', XMLDB_TYPE_INTEGER, '1', null, null, null, null, 'visibleold');
+
+        if (!$dbman->field_exists($table, $field)) {
+            $dbman->add_field($table, $field);
+        }
+
+        // Main savepoint reached.
+        upgrade_main_savepoint(true, 2021052500.32);
+    }
+
     return true;
 }

lib/navigationlib.php

@@ -4448,7 +4448,7 @@ class settings_navigation extends navigation_node {
      * @return navigation_node|false
      */
     protected function load_course_settings($forceopen = false) {
-        global $CFG;
+        global $CFG, $USER;
         require_once($CFG->dirroot . '/course/lib.php');
 
         $course = $this->page->course;
@@ -4605,6 +4605,16 @@ class settings_navigation extends navigation_node {
             }
         }
 
+        // Prepare data for course content download functionality if it is enabled.
+        // Will only be included here if the action menu is already in use, otherwise a button will be added to the UI elsewhere.
+        if (\core\content::can_export_context($coursecontext, $USER) && !empty($coursenode->get_children_key_list())) {
+            $linkattr = \core_course\output\content_export_link::get_attributes($coursecontext);
+            $actionlink = new action_link($linkattr->url, $linkattr->displaystring, null, $linkattr->elementattributes);
+
+            $coursenode->add($linkattr->displaystring, $actionlink, self::TYPE_SETTING, null, 'download',
+                    new pix_icon('t/download', ''));
+        }
+
         // Return we are done
         return $coursenode;
     }

lib/tests/content_test.php

@@ -0,0 +1,119 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Unit tests for core\content class.
+ *
+ * @package     core
+ * @category    test
+ * @copyright   2020 Michael Hawkins <[email protected]>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core;
+
+/**
+ * Unit tests for core\content class.
+ *
+ * @package     core
+ * @category    test
+ * @copyright   2020 Michael Hawkins <[email protected]>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class content_test extends \advanced_testcase {
+
+    /**
+     * A test to confirm only valid cases allow exporting of course content.
+     */
+    public function test_can_export_context_course() {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $course2 = $this->getDataGenerator()->create_course();
+        $course1context = \context_course::instance($course1->id);
+        $course2context = \context_course::instance($course2->id);
+
+        // Enrol user as student in course1 only.
+        $user = $this->getDataGenerator()->create_and_enrol($course1, 'student');
+
+        // Confirm by default enrolled user does not have permission to export in course1.
+        $this->assertFalse(content::can_export_context($course1context, $user));
+
+        // Make course download available on site, but not enabled in course1 or by default.
+        set_config('downloadcoursecontentallowed', true);
+
+        // Confirm user still does not have permission to export (disabled in courses by default).
+        $this->assertFalse(content::can_export_context($course1context, $user));
+
+        // Enable export in courses by default.
+        set_config('downloadcontentsitedefault', DOWNLOAD_COURSE_CONTENT_ENABLED, 'moodlecourse');
+
+        // Confirm user now has permission to export in course1 only.
+        $this->assertTrue(content::can_export_context($course1context, $user));
+
+        // Disable course downloads in course1.
+        $course1->downloadcontent = DOWNLOAD_COURSE_CONTENT_DISABLED;
+        $DB->update_record('course', $course1);
+        rebuild_course_cache($course1->id);
+
+        // Confirm user does not have permission to export in course1.
+        $this->assertFalse(content::can_export_context($course1context, $user));
+
+        // Enable course downloads in course1.
+        $course1->downloadcontent = DOWNLOAD_COURSE_CONTENT_ENABLED;
+        $DB->update_record('course', $course1);
+        rebuild_course_cache($course1->id);
+
+        // Confirm user has permission to export in course1.
+        $this->assertTrue(content::can_export_context($course1context, $user));
+
+        // Confirm user does not have permission to export in course they are not enrolled in (course2).
+        $this->assertFalse(content::can_export_context($course2context, $user));
+
+        // Disable export in courses by default.
+        set_config('downloadcontentsitedefault', DOWNLOAD_COURSE_CONTENT_DISABLED, 'moodlecourse');
+
+        // Confirm user still has permission to export in course1 (still enabled at the course level).
+        $this->assertTrue(content::can_export_context($course1context, $user));
+
+        // Disable the course downloads feature.
+        set_config('downloadcoursecontentallowed', false);
+
+        // Confirm user no longer has permission to export in course1.
+        $this->assertFalse(content::can_export_context($course1context, $user));
+    }
+
+    /**
+     * A test to confirm unsupported contexts will return false when checking whether content can be exported.
+     */
+    public function test_can_export_context_unsupported_context() {
+        $this->resetAfterTest();
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $systemcontext = \context_system::instance();
+
+        // Enrol user as student in course1 only.
+        $user = $this->getDataGenerator()->create_and_enrol($course1, 'student');
+
+        // Make course download available on site (course context).
+        set_config('downloadcoursecontentallowed', true);
+
+        // Confirm system context does not gain permission to export content.
+        $this->assertFalse(content::can_export_context($systemcontext, $user));
+    }
+}

version.php

@@ -29,7 +29,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$version  = 2021052500.31;              // YYYYMMDD      = weekly release date of this DEV branch.
+$version  = 2021052500.32;              // YYYYMMDD      = weekly release date of this DEV branch.
                                         //         RR    = release increments - 00 in DEV branches.
                                         //           .XX = incremental changes.
 $release  = '4.0dev (Build: 20201023)'; // Human-friendly version name