Merge branch 'comment-thumbnail-generation' into 'master'

utils/thumbnails: document thumbnail url usage

See merge request !435

website/utils/templatetags/thumbnail.py

@@ -31,6 +31,9 @@ def thumbnail(path, size, fit=True):
             os.path.getmtime(full_path) > os.path.getmtime(full_thumbpath)):
         pathuri = urlquote(path, safe=[''])
         thumburi = urlquote(thumbpath, safe=[''])
+        # We provide a URL instead of calling it as a function, so that using
+        # it means kicking off a new GET request. If we would generate all
+        # thumbnails inline, loading an album overview would have high latency.
         return reverse('generate-thumbnail',
                        args=[size_fit, pathuri, thumburi])
 
@@ -41,4 +44,7 @@ def thumbnail(path, size, fit=True):
         return settings.MEDIA_URL + thumbpath
 
     # Otherwise simply place it in media/thumbnails.
+    # We provide a URL instead of calling it as a function, so that using
+    # it means kicking off a new GET request. If we would generate all
+    # thumbnails inline, loading an album overview would have high latency.
     return reverse('private-thumbnails', args=[size_fit, path])