diff --git a/inventory_provider/tasks/common.py b/inventory_provider/tasks/common.py
index 3125c81071c826a9bd8e2e03c81817d3fb730041..292800572d841b3474714e68750faeeb3108dc63 100644
--- a/inventory_provider/tasks/common.py
+++ b/inventory_provider/tasks/common.py
@@ -31,9 +31,9 @@ TASK_LOG_SCHEMA = {
         'meta': {
             'type': 'object',
             'properties': {
-                'task': {'type': ['string', 'null']},
-                'id': {'type': ['string', 'null']},
-                'worker': {'type': ['string', 'null']},
+                'task': {'type': 'string'},
+                'id': {'type': 'string'},
+                'worker': {'type': 'string'},
                 'pid': {'type': 'integer'},
                 'warning': {'type': 'boolean'},
                 'error': {'type': 'boolean'},