From 51d31432c875644abfcaee8f9fe2e32e9481ab0c Mon Sep 17 00:00:00 2001
From: Andrew Nicols <andrew@nicols.co.uk>
Date: Tue, 23 Jan 2018 09:48:05 +0800
Subject: [PATCH] MDL-61253 repository: Add referenced files to archives

---
 lib/filestorage/stored_file.php | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/filestorage/stored_file.php b/lib/filestorage/stored_file.php
index c1a4254c8f0..0f67664bdfb 100644
--- a/lib/filestorage/stored_file.php
+++ b/lib/filestorage/stored_file.php
@@ -537,6 +537,18 @@ class stored_file {
      * @return bool success
      */
     public function archive_file(file_archive $filearch, $archivepath) {
+        if ($this->repository) {
+            $this->sync_external_file();
+            if ($this->compare_to_string('')) {
+                // This file is not stored locally - attempt to retrieve it from the repository.
+                // This may happen if the repository deliberately does not fetch files, or if there is a failure with the sync.
+                $fileinfo = $this->repository->get_file($this->get_reference());
+                if (isset($fileinfo['path'])) {
+                    return $filearch->add_file_from_pathname($archivepath, $fileinfo['path']);
+                }
+            }
+        }
+
         return $this->filesystem->add_storedfile_to_archive($this, $filearch, $archivepath);
     }