fix nesting of pod data under kubernetes in system info (#402)

fixes #401
closes #402

Author: beniwohli

CHANGELOG.md

@@ -6,6 +6,7 @@
  * Moved context.url to context.http.url for requests/urllib3 spans (#393, #394)
  * Added support for using route as transaction name in Django 2.2+ (#86, #396)
  * Fixed an issue with custom user models in Django using non-string usernames (#397, #398)
+ * Fixed an issue with sending kubernetes metadata to the API (#401, #402)
 
 ## v4.1.0 
 [Check the diff](https://github.com/elastic/apm-agent-python/compare/v4.0.3...v4.1.0)

elasticapm/utils/cgroup.py

@@ -70,6 +70,6 @@ def parse_cgroups(filehandle):
             pod_id = kubepods_match.group(1)
             if not pod_id:
                 pod_id = kubepods_match.group(2)
-            return {"container": {"id": container_id}, "pod": {"uid": pod_id}}
+            return {"container": {"id": container_id}, "kubernetes": {"pod": {"uid": pod_id}}}
         elif container_id_regexp.match(container_id):
             return {"container": {"id": container_id}}

tests/utils/cgroup_tests.py

@@ -19,14 +19,14 @@
             "1:name=systemd:/kubepods/besteffort/pode9b90526-f47d-11e8-b2a5-080027b9f4fb/15aa6e53-b09a-40c7-8558-c6c31e36c88a",
             {
                 "container": {"id": "15aa6e53-b09a-40c7-8558-c6c31e36c88a"},
-                "pod": {"uid": "e9b90526-f47d-11e8-b2a5-080027b9f4fb"},
+                "kubernetes": {"pod": {"uid": "e9b90526-f47d-11e8-b2a5-080027b9f4fb"}},
             },
         ),
         (
             "1:name=systemd:/kubepods.slice/kubepods-burstable.slice/kubepods-burstable-pod90d81341_92de_11e7_8cf2_507b9d4141fa.slice/crio-2227daf62df6694645fee5df53c1f91271546a9560e8600a525690ae252b7f63.scope",
             {
                 "container": {"id": "2227daf62df6694645fee5df53c1f91271546a9560e8600a525690ae252b7f63"},
-                "pod": {"uid": "90d81341_92de_11e7_8cf2_507b9d4141fa"},
+                "kubernetes": {"pod": {"uid": "90d81341_92de_11e7_8cf2_507b9d4141fa"}},
             },
         ),
     ],