Don't save empty filepath and log the error. fix #389

couchpotato/core/plugins/library/main.py

@@ -117,13 +117,14 @@ class LibraryPlugin(Plugin):
                         continue
 
                     file_path = fireEvent('file.download', url = image, single = True)
-                    file_obj = fireEvent('file.add', path = file_path, type_tuple = ('image', type), single = True)
-                    try:
-                        file_obj = db.query(File).filter_by(id = file_obj.get('id')).one()
-                        library.files.append(file_obj)
-                        db.commit()
-                    except:
-                        log.debug('Failed to attach to library: %s', traceback.format_exc())
+                    if file_path:
+                        file_obj = fireEvent('file.add', path = file_path, type_tuple = ('image', type), single = True)
+                        try:
+                            file_obj = db.query(File).filter_by(id = file_obj.get('id')).one()
+                            library.files.append(file_obj)
+                            db.commit()
+                        except:
+                            log.debug('Failed to attach to library: %s', traceback.format_exc())
 
             library_dict = library.to_dict(self.default_dict)