schema: Log debug instead of warning when jsonschema is not available.

When operating in expected path, cloud-init should avoid logging with
warning. That causes 'WARNING' messages in /var/log/cloud-init.log.
By default, warnings also go to the console.

Since jsonschema is a optional dependency, and not present on xenial
and zesty, cloud-init should not warn there.

Also here:
* Add a test to integration tests to assert that there are no
  warnings in /var/log/cloud-init.log.
* Update one integration test that did show warning and the related
  documentation and examples.

LP: #1724354

1 files changed, 4 insertions, 0 deletions

diff --git a/tests/cloud_tests/testcases/base.py b/tests/cloud_tests/testcases/base.py
index bb545ab9..b2b5b4b1 100644
--- a/tests/cloud_tests/testcases/base.py
+++ b/tests/cloud_tests/testcases/base.py
@@ -72,6 +72,10 @@ class CloudTestCase(unittest.TestCase):
         result = self.get_status_data(self.get_data_file('result.json'))
         self.assertEqual(len(result['errors']), 0)
 
+    def test_no_warnings_in_log(self):
+        """Warnings should not be found in the log."""
+        self.assertNotIn("WARN", self.get_data_file('cloud-init.log'))
+
 
 class PasswordListTest(CloudTestCase):
     """Base password test case class."""