Add full traceback to ExceptionPayload in versioned notifications

This patch adds full traceback to ExceptionPayload in versioned
notifications.

The instance fault field and instance-action REST API has already
provide the traceback to the admin users (controlable through policy)
and the notifications are also admin only things as they are emitted
to the message bus by default. So it is assumed that security is not
a bigger concern for the notification than for the REST API.

On the ML [1] post there was no objection to add new string field to the
ExceptionPayload that will hold the serialized traceback object.

[1] http://lists.openstack.org/pipermail/openstack-dev/2018-March/128105.html

Implements: blueprint add-full-traceback-to-error-notifications

Change-Id: Id587967ea4f9980c292492e2f659bf55fb037b28

1 files changed, 9 insertions, 5 deletions

diff --git a/nova/notifications/objects/exception.py b/nova/notifications/objects/exception.py
index e0e5016f47..6ebb927b27 100644
--- a/nova/notifications/objects/exception.py
+++ b/nova/notifications/objects/exception.py
@@ -21,24 +21,27 @@ from nova.objects import fields
 @nova_base.NovaObjectRegistry.register_notification
 class ExceptionPayload(base.NotificationPayloadBase):
     # Version 1.0: Initial version
-    VERSION = '1.0'
+    # Version 1.1: Add traceback field to ExceptionPayload
+    VERSION = '1.1'
     fields = {
         'module_name': fields.StringField(),
         'function_name': fields.StringField(),
         'exception': fields.StringField(),
-        'exception_message': fields.StringField()
+        'exception_message': fields.StringField(),
+        'traceback': fields.StringField()
     }
 
     def __init__(self, module_name, function_name, exception,
-                 exception_message):
+                 exception_message, traceback):
         super(ExceptionPayload, self).__init__()
         self.module_name = module_name
         self.function_name = function_name
         self.exception = exception
         self.exception_message = exception_message
+        self.traceback = traceback
 
     @classmethod
-    def from_exception(cls, fault):
+    def from_exc_and_traceback(cls, fault, traceback):
         trace = inspect.trace()[-1]
         # TODO(gibi): apply strutils.mask_password on exception_message and
         # consider emitting the exception_message only if the safe flag is
@@ -49,7 +52,8 @@ class ExceptionPayload(base.NotificationPayloadBase):
                 function_name=trace[3],
                 module_name=module_name,
                 exception=fault.__class__.__name__,
-                exception_message=six.text_type(fault))
+                exception_message=six.text_type(fault),
+                traceback=traceback)
 
 
 @base.notification_sample('compute-exception.json')