Monkey patch original current_thread _active

Monkey patch the original current_thread to use the up-to-date _active
global variable. This solution is based on that documented at:
eventlet/eventlet#592

Change-Id: I35335325828c10f7a0a1c97edfd1a842dda77577
Story: 2007614

barbican/cmd/keystone_listener.py

@@ -27,6 +27,12 @@
 # To have remote debugging, thread module needs to be disabled.
 # eventlet.monkey_patch(thread=False)
 eventlet.monkey_patch()
+# Monkey patch the original current_thread to use the up-to-date _active
+# global variable. See https://bugs.launchpad.net/bugs/1863021 and
+# https://github.com/eventlet/eventlet/issues/592
+import __original_module_threading as orig_threading
+import threading  # noqa
+orig_threading.current_thread.__globals__['_active'] = threading._active
 
 
 # 'Borrowed' from the Glance project:

barbican/cmd/retry_scheduler.py

@@ -25,6 +25,12 @@
 
 # Oslo messaging RPC server uses eventlet.
 eventlet.monkey_patch()
+# Monkey patch the original current_thread to use the up-to-date _active
+# global variable. See https://bugs.launchpad.net/bugs/1863021 and
+# https://github.com/eventlet/eventlet/issues/592
+import __original_module_threading as orig_threading
+import threading  # noqa
+orig_threading.current_thread.__globals__['_active'] = threading._active
 
 # 'Borrowed' from the Glance project:
 # If ../barbican/__init__.py exists, add ../ to Python search path, so that

barbican/cmd/worker.py

@@ -25,6 +25,12 @@
 
 # Oslo messaging RPC server uses eventlet.
 eventlet.monkey_patch()
+# Monkey patch the original current_thread to use the up-to-date _active
+# global variable. See https://bugs.launchpad.net/bugs/1863021 and
+# https://github.com/eventlet/eventlet/issues/592
+import __original_module_threading as orig_threading
+import threading  # noqa
+orig_threading.current_thread.__globals__['_active'] = threading._active
 
 # 'Borrowed' from the Glance project:
 # If ../barbican/__init__.py exists, add ../ to Python search path, so that