POC: replace our external log aggregation feature with rsyslog

- this change adds rsyslog (https://github.com/rsyslog/rsyslog) as
  a new service that runs on every AWX node (managed by supervisord)
  in particular, this feature requires a recent version (v8.38+) of
  rsyslog that supports the omhttp module
  (https://github.com/rsyslog/rsyslog-doc/pull/750)
- the "external_logger" handler in AWX is now a SysLogHandler that ships
  logs to the local UDP port where rsyslog is configured to listen (by
  default, 51414)
- every time a LOG_AGGREGATOR_* setting is changed, every AWX node
  reconfigures and restarts its local instance of rsyslog so that its
  fowarding settings match what has been configured in AWX
- unlike the prior implementation, if the external logging aggregator
  (splunk/logstash) goes temporarily offline, rsyslog will retain the
  messages and ship them when the log aggregator is back online
- 4xx or 5xx level errors are recorded at /var/log/tower/external.err

awx/conf/views.py

@@ -3,6 +3,7 @@
 
 # Python
 import collections
+import logging
 import sys
 
 # Django
@@ -26,7 +27,6 @@ from awx.api.generics import (
 from awx.api.permissions import IsSuperUser
 from awx.api.versioning import reverse
 from awx.main.utils import camelcase_to_underscore
-from awx.main.utils.handlers import AWXProxyHandler, LoggingConnectivityException
 from awx.main.tasks import handle_setting_changes
 from awx.conf.models import Setting
 from awx.conf.serializers import SettingCategorySerializer, SettingSingletonSerializer
@@ -161,40 +161,8 @@ class SettingLoggingTest(GenericAPIView):
     filter_backends = []
 
     def post(self, request, *args, **kwargs):
-        defaults = dict()
-        for key in settings_registry.get_registered_settings(category_slug='logging'):
-            try:
-                defaults[key] = settings_registry.get_setting_field(key).get_default()
-            except serializers.SkipField:
-                defaults[key] = None
-        obj = type('Settings', (object,), defaults)()
-        serializer = self.get_serializer(obj, data=request.data)
-        serializer.is_valid(raise_exception=True)
-        # Special validation specific to logging test.
-        errors = {}
-        for key in ['LOG_AGGREGATOR_TYPE', 'LOG_AGGREGATOR_HOST']:
-            if not request.data.get(key, ''):
-                errors[key] = 'This field is required.'
-        if errors:
-            raise ValidationError(errors)
-
-        if request.data.get('LOG_AGGREGATOR_PASSWORD', '').startswith('$encrypted$'):
-            serializer.validated_data['LOG_AGGREGATOR_PASSWORD'] = getattr(
-                settings, 'LOG_AGGREGATOR_PASSWORD', ''
-            )
-
-        try:
-            class MockSettings:
-                pass
-            mock_settings = MockSettings()
-            for k, v in serializer.validated_data.items():
-                setattr(mock_settings, k, v)
-            AWXProxyHandler().perform_test(custom_settings=mock_settings)
-            if mock_settings.LOG_AGGREGATOR_PROTOCOL.upper() == 'UDP':
-                return Response(status=status.HTTP_201_CREATED)
-        except LoggingConnectivityException as e:
-            return Response({'error': str(e)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
-        return Response(status=status.HTTP_200_OK)
+        logging.getLogger('awx').info('AWX Connection Test')
+        return Response(status=status.HTTP_202_ACCEPTED)
 
 
 # Create view functions for all of the class-based views to simplify inclusion