Support for lazily instantiated loggers

As part of code review for LP #1161031, there was a suggestion
to lazily instantiate the logger in oslo. The use case was when
creating LOG at a module level when we have not yet called
logging.setup, we needed a way to delay creating actual loggers

Added a handlers property in ContextAdapter so the existing testcase
can be used for lazy loggers as well

Change-Id: Iae2e379f8a0d2d38836645e7648294dee97deaaa

1 files changed, 19 insertions, 4 deletions

diff --git a/tests/unit/test_log.py b/tests/unit/test_log.py
index 4241e2e..a80b872 100644
--- a/tests/unit/test_log.py
+++ b/tests/unit/test_log.py
@@ -20,17 +20,20 @@ def _fake_context():
     return context.RequestContext(1, 1)
 
 
-class LoggerTestCase(test_utils.BaseTestCase):
+class CommonLoggerTestsMixIn(object):
+    """These tests are shared between LoggerTestCase and
+    LazyLoggerTestCase.
+    """
+
     def setUp(self):
-        super(LoggerTestCase, self).setUp()
+        super(CommonLoggerTestsMixIn, self).setUp()
 
         # common context has different fields to the defaults in log.py
         self.config(logging_context_format_string='%(asctime)s %(levelname)s '
                                                   '%(name)s [%(request_id)s '
                                                   '%(user)s %(tenant)s] '
                                                   '%(message)s')
-
-        self.log = log.getLogger()
+        self.log = None
 
     def test_handlers_have_legacy_formatter(self):
         formatters = []
@@ -73,6 +76,18 @@ class LoggerTestCase(test_utils.BaseTestCase):
             self.assertRaises(AttributeError, getattr, log, func)
 
 
+class LoggerTestCase(CommonLoggerTestsMixIn, test_utils.BaseTestCase):
+    def setUp(self):
+        super(LoggerTestCase, self).setUp()
+        self.log = log.getLogger()
+
+
+class LazyLoggerTestCase(CommonLoggerTestsMixIn, test_utils.BaseTestCase):
+    def setUp(self):
+        super(LazyLoggerTestCase, self).setUp()
+        self.log = log.getLazyLogger()
+
+
 class LogHandlerTestCase(test_utils.BaseTestCase):
     def test_log_path_logdir(self):
         self.config(log_dir='/some/path', log_file=None)