gcp_utils: Handle JSON decode exception (#59427)

Handle json.loads exception rather than providing stacktrace

Fixes: #56269

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

lib/ansible/module_utils/gcp_utils.py

@@ -18,7 +18,7 @@ except ImportError:
 
 from ansible.module_utils.basic import AnsibleModule, env_fallback
 from ansible.module_utils.six import string_types
-from ansible.module_utils._text import to_text
+from ansible.module_utils._text import to_text, to_native
 import ast
 import os
 import json
@@ -156,7 +156,12 @@ class GcpSession(object):
             path = os.path.realpath(os.path.expanduser(self.module.params['service_account_file']))
             return service_account.Credentials.from_service_account_file(path).with_scopes(self.module.params['scopes'])
         elif cred_type == 'serviceaccount' and self.module.params.get('service_account_contents'):
+            try:
                 cred = json.loads(self.module.params.get('service_account_contents'))
+            except json.decoder.JSONDecodeError as e:
+                self.module.fail_json(
+                    msg="Unable to decode service_account_contents as JSON : %s" % to_native(e)
+                )
             return service_account.Credentials.from_service_account_info(cred).with_scopes(self.module.params['scopes'])
         elif cred_type == 'machineaccount':
             return google.auth.compute_engine.Credentials(