MDL-39617 Add cli backup script for a single course backing up.

Useful for backing up a single course. Accepts parameters:

--courseid=INTEGER        Course ID for backup
--courseshortname=STRING  Course shortname for backup.
--destination=STRING      Path where to store backup file. If not set, the backup
                          will stored within the same course backup area.

admin/cli/backup.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/>.
+
+/**
+ * This script allows to do backup.
+ *
+ * @package    core
+ * @subpackage cli
+ * @copyright  2013 Lancaster University
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+define('CLI_SCRIPT', 1);
+
+require(dirname(dirname(dirname(__FILE__))).'/config.php');
+require_once($CFG->libdir.'/clilib.php');
+require_once($CFG->dirroot . '/backup/util/includes/backup_includes.php');
+
+// Now get cli options.
+list($options, $unrecognized) = cli_get_params(array(
+    'courseid' => false,
+    'courseshortname' => '',
+    'destination' => '',
+    'help' => false,
+    ), array('h' => 'help'));
+
+if ($unrecognized) {
+    $unrecognized = implode("\n  ", $unrecognized);
+    cli_error(get_string('cliunknowoption', 'admin', $unrecognized));
+}
+
+if ($options['help'] || !($options['courseid'] || $options['courseshortname'])) {
+    $help = <<<EOL
+Perform backup of the given course.
+
+Options:
+--courseid=INTEGER          Course ID for backup,
+--courseshortname=STRING    Course shortname for backup,
+--destination=STRING        Path where to store backup file. If not set, the backup
+                            will stored within the same course backup area.
+-h, --help                  Print out this help
+
+Example:
+\$sudo -u www-data /usr/bin/php admin/cli/backup.php --courseid=2 --destination=/moodle/backup/\n
+EOL;
+
+    echo $help;
+    die;
+}
+
+$admin = get_admin();
+if (!$admin) {
+    mtrace("Error: No admin account was found");
+    die;
+}
+
+// Do we need to store backup somewhere else?
+$dir = rtrim($options['destination'], '/');
+if (!empty($dir)) {
+    if (!file_exists($dir) || !is_dir($dir) || !is_writable($dir)) {
+        mtrace("Destination directory does not exists or not writable.");
+        die;
+    }
+}
+
+// Check that the course exists.
+if ($options['courseid']) {
+    $course = $DB->get_record('course', array('id' => $options['courseid']), '*', MUST_EXIST);
+} else if ($options['courseshortname']) {
+    $course = $DB->get_record('course', array('shortname' => $options['courseshortname']), '*', MUST_EXIST);
+}
+
+cli_heading('Performing back-up...');
+$bc = new backup_controller(backup::TYPE_1COURSE, $course->id, backup::FORMAT_MOODLE,
+                            backup::INTERACTIVE_YES, backup::MODE_GENERAL, $admin->id);
+// Set the default filename.
+$format = $bc->get_format();
+$type = $bc->get_type();
+$id = $bc->get_id();
+$users = $bc->get_plan()->get_setting('users')->get_value();
+$anonymised = $bc->get_plan()->get_setting('anonymize')->get_value();
+$filename = backup_plan_dbops::get_default_backup_filename($format, $type, $id, $users, $anonymised);
+$bc->get_plan()->get_setting('filename')->set_value($filename);
+
+// Execution.
+$bc->finish_ui();
+$bc->execute_plan();
+$results = $bc->get_results();
+$file = $results['backup_destination']; // May be empty if file already moved to target location.
+
+// Do we need to store backup somewhere else?
+if (!empty($dir)) {
+    if ($file) {
+        mtrace("Writing " . $dir.'/'.$filename);
+        if ($file->copy_content_to($dir.'/'.$filename)) {
+            $file->delete();
+            mtrace("Backup is completed.");
+        } else {
+            mtrace("Destination directory does not exists or not writable. Leaving the file in the course backup area.");
+        }
+    }
+} else {
+    mtrace("Backup is done, the new file is listed in the backup area of the given course");
+}
+$bc->destroy();
+exit(0);