$metadata->thumbnail_url is not guaranteed to be set

We should probably have a separate class for this, so we can more
easily combine different technologies similar to oEmbed/OpenGraph.

diff --git a/plugins/Oembed/OembedPlugin.php b/plugins/Oembed/OembedPlugin.php
index c90f57439b3a2983ab9037ca43bce0e820603619..44e4ac93180679d1baccba90fb6bb66bc74a25b8 100644 (file)
--- a/plugins/Oembed/OembedPlugin.php
+++ b/plugins/Oembed/OembedPlugin.php
@@ -73,18 +73,20 @@ class OembedPlugin extends Plugin
             $metadata = OpenGraphHelper::ogFromHtml($dom);
         }
 
-        // sometimes sites serve the path, not the full URL, for images
-        // let's "be liberal in what you accept from others"!
-        // add protocol and host if the thumbnail_url starts with /
-        if(substr($metadata->thumbnail_url,0,1) == '/') {
-            $thumbnail_url_parsed = parse_url($metadata->url);
-            $metadata->thumbnail_url = $thumbnail_url_parsed['scheme']."://".$thumbnail_url_parsed['host'].$metadata->thumbnail_url;
-        } 
+        if (isset($metadata->thumbnail_url)) {
+            // sometimes sites serve the path, not the full URL, for images
+            // let's "be liberal in what you accept from others"!
+            // add protocol and host if the thumbnail_url starts with /
+            if(substr($metadata->thumbnail_url,0,1) == '/') {
+                $thumbnail_url_parsed = parse_url($metadata->url);
+                $metadata->thumbnail_url = $thumbnail_url_parsed['scheme']."://".$thumbnail_url_parsed['host'].$metadata->thumbnail_url;
+            }
         
-        // some wordpress opengraph implementations sometimes return a white blank image
-        // no need for us to save that!
-        if($metadata->thumbnail_url == 'https://s0.wp.com/i/blank.jpg') {
-            unset($metadata->thumbnail_url);
+            // some wordpress opengraph implementations sometimes return a white blank image
+            // no need for us to save that!
+            if($metadata->thumbnail_url == 'https://s0.wp.com/i/blank.jpg') {
+                unset($metadata->thumbnail_url);
+            }
         }
 
     }