Move set warnings filters to logging module

This is the first step in moving logging out of shell.py

Change-Id: I3dcb4e17bb4687988ddf9b793ad1a308ef89b242
Implements: blueprint logging-migration

openstackclient/common/context.py

@@ -14,6 +14,7 @@
 """Context and Formatter"""
 
 import logging
+import warnings
 
 _LOG_MESSAGE_FORMAT = ('%(asctime)s.%(msecs)03d %(process)d '
                        '%(levelname)s %(name)s [%(clouds_name)s '
@@ -21,6 +22,15 @@ _LOG_MESSAGE_FORMAT = ('%(asctime)s.%(msecs)03d %(process)d '
 _LOG_DATE_FORMAT = '%Y-%m-%d %H:%M:%S'
 
 
+def set_warning_filter(log_level):
+    if log_level == logging.ERROR:
+        warnings.simplefilter("ignore")
+    elif log_level == logging.WARNING:
+        warnings.simplefilter("ignore")
+    elif log_level == logging.INFO:
+        warnings.simplefilter("once")
+
+
 def setup_handler_logging_level(handler_type, level):
     """Setup of the handler for set the logging level
 

openstackclient/shell.py

@@ -20,7 +20,6 @@ import getpass
 import logging
 import sys
 import traceback
-import warnings
 
 from cliff import app
 from cliff import command
@@ -117,18 +116,16 @@ class OpenStackShell(app.App):
         if self.options.verbose_level == 0:
             # --quiet
             log_level = logging.ERROR
-            warnings.simplefilter("ignore")
         elif self.options.verbose_level == 1:
             # This is the default case, no --debug, --verbose or --quiet
             log_level = logging.WARNING
-            warnings.simplefilter("ignore")
         elif self.options.verbose_level == 2:
             # One --verbose
             log_level = logging.INFO
-            warnings.simplefilter("once")
         elif self.options.verbose_level >= 3:
             # Two or more --verbose
             log_level = logging.DEBUG
+        context.set_warning_filter(log_level)
 
         # Set the handler logging level of FileHandler(--log-file)
         # and StreamHandler

openstackclient/tests/common/test_context.py

@@ -62,6 +62,15 @@ class TestContext(utils.TestCase):
         context.setup_logging(shell, cloud_config)
         self.assertEqual(True, shell.enable_operation_logging)
 
+    @mock.patch('warnings.simplefilter')
+    def test_set_warning_filter(self, simplefilter):
+        context.set_warning_filter(logging.ERROR)
+        simplefilter.assert_called_with("ignore")
+        context.set_warning_filter(logging.WARNING)
+        simplefilter.assert_called_with("ignore")
+        context.set_warning_filter(logging.INFO)
+        simplefilter.assert_called_with("once")
+
 
 class Test_LogContext(utils.TestCase):
     def setUp(self):