[2.9] Handle set object retrieved from lookup plugin (#69901)

self.client.resources.api_groups is a dict_keys and is not
handled correctly by default callback plugin while JSON serialization.

This fix will typecast it to list so that it can be JSON serialized for
further processing.

Fixes: ansible-collection/community.kubernetes#111

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

changelogs/fragments/i111_k8s_lookup.yml

@@ -0,0 +1,2 @@
+bugfixes:
+- k8s - Handle set object retrieved from lookup plugin.

lib/ansible/plugins/lookup/k8s.py

@@ -1,30 +1,13 @@
 #
-#  Copyright 2018 Red Hat | Ansible
+# Copyright: (c) 2018, Red Hat | Ansible
-#
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
-# This file is part of Ansible
-#
-# Ansible is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# Ansible is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
 
 from __future__ import (absolute_import, division, print_function)
-
 __metaclass__ = type
 
-DOCUMENTATION = """
+DOCUMENTATION = r"""
     lookup: k8s
-
     version_added: "2.5"
-
     short_description: Query the K8s API
 
     description:
@@ -132,7 +115,7 @@ DOCUMENTATION = """
         additional information visit https://github.com/openshift/openshift-restclient-python"
 """
 
-EXAMPLES = """
+EXAMPLES = r"""
 - name: Fetch a list of namespaces
   set_fact:
     projects: "{{ lookup('k8s', api_version='v1', kind='Namespace') }}"
@@ -168,7 +151,7 @@ EXAMPLES = """
     service: "{{ lookup('k8s', src='service.yml') }}"
 """
 
-RETURN = """
+RETURN = r"""
   _list:
     description:
       - One ore more object definitions returned from the API.
@@ -196,12 +179,12 @@ RETURN = """
         type: complex
 """
 
-from ansible.plugins.lookup import LookupBase
-
-from ansible.module_utils.k8s.common import K8sAnsibleMixin
 
 from ansible.errors import AnsibleError
+from ansible.module_utils.common._collections_compat import KeysView
+from ansible.plugins.lookup import LookupBase
 
+from ansible.module_utils.k8s.common import K8sAnsibleMixin
 
 try:
     from openshift.dynamic import DynamicClient
@@ -255,6 +238,8 @@ class KubernetesLookup(K8sAnsibleMixin):
         if cluster_info == 'version':
             return [self.client.version]
         if cluster_info == 'api_groups':
+            if isinstance(self.client.resources.api_groups, KeysView):
+                return [list(self.client.resources.api_groups)]
             return [self.client.resources.api_groups]
 
         self.kind = kwargs.get('kind')