1 files changed, 15 insertions, 5 deletions
diff --git a/lib/Utility/OPMLExporter.php b/lib/Utility/OPMLExporter.php
index aa06f5dbf..bb813daf8 100644
--- a/lib/Utility/OPMLExporter.php
+++ b/lib/Utility/OPMLExporter.php
@@ -90,11 +90,21 @@ class OPMLExporter
     protected function createFeedOutline(Feed $feed, DOMDocument $document)
     {
         $feedOutline = $document->createElement('outline');
-        $feedOutline->setAttribute('title', $feed->getTitle());
-        $feedOutline->setAttribute('text', $feed->getTitle());
-        $feedOutline->setAttribute('type', 'rss');
-        $feedOutline->setAttribute('xmlUrl', $feed->getUrl());
-        $feedOutline->setAttribute('htmlUrl', $feed->getLink());
+        $attributes = [
+            ['title', $feed->getTitle()],
+            ['text', $feed->getTitle()],
+            ['type', 'rss'],
+            ['xmlUrl', $feed->getUrl()],
+            ['htmlUrl', $feed->getLink()],
+        ];
+
+        foreach ($attributes as $attribute) {
+            if (is_null($attribute[1])) {
+                $feedOutline->setAttribute($attribute[0], "");
+            } else {
+                $feedOutline->setAttribute($attribute[0], $attribute[1]);
+            }
+        }
 
         return $feedOutline;
     }