Merge pull request #5043 from StackStorm/py2_warning_logs

Add warning messages to logs if StackStorm running with python 2

Author: amanda11

CHANGELOG.rst

@@ -23,6 +23,11 @@ Added
   Python 2. (new feature) #5037
 
   Contributed by @amanda11
+* Added deprecation warning to each StackStorm service log, if service is running with
+  Python 2. (new feature) #5043
+
+  Contributed by @amanda11
+
 
 Changed
 ~~~~~~~

st2common/st2common/constants/error_messages.py

@@ -15,7 +15,8 @@
 
 __all__ = [
     'PACK_VIRTUALENV_DOESNT_EXIST',
-    'PACK_VIRTUALENV_USES_PYTHON3'
+    'PACK_VIRTUALENV_USES_PYTHON3',
+    'PYTHON2_DEPRECATION'
 ]
 
 PACK_VIRTUALENV_DOESNT_EXIST = '''
@@ -32,3 +33,10 @@
 virtual environment with python2 binary:
 "st2 run packs.setup_virtualenv packs=%(pack)s python3=false"
 '''
+
+PYTHON2_DEPRECATION = 'DEPRECATION WARNING. Support for python 2 will be removed in future ' \
+                      'StackStorm releases. Please ensure that all packs used are python ' \
+                      '3 compatible. Your StackStorm installation may be upgraded from ' \
+                      'python 2 to python 3 in future platform releases. It is recommended ' \
+                      'to plan the manual migration to a python 3 native platform, e.g. ' \
+                      'Ubuntu 18.04 LTS or CentOS/RHEL 8.'

st2common/st2common/service_setup.py

@@ -42,6 +42,7 @@
 from st2common.util import system_info
 from st2common.services import coordination
 from st2common.logging.misc import add_global_filters_for_all_loggers
+from st2common.constants.error_messages import PYTHON2_DEPRECATION
 
 # Note: This is here for backward compatibility.
 # Function has been moved in a standalone module to avoid expensive in-direct
@@ -186,6 +187,9 @@ def setup(service, config, setup_db=True, register_mq_exchanges=True,
         register_service_in_service_registry(service=service, capabilities=capabilities,
                                              start_heart=True)
 
+    if sys.version_info[0] == 2:
+        LOG.warning(PYTHON2_DEPRECATION)
+
 
 def teardown():
     """