Record node history and manage events in db

* Adds periodic task to purge node_history entries based upon
  provided configuration.
* Adds recording of node history entries for errors in the
  core conductor code.
* Also changes the rescue abort behavior to remove the notice
  from being recorded as an error, as this is a likely bug in
  behavior for any process or service evaluating the node
  last_error field.
* Makes use of a semi-free form event_type field to help
  provide some additional context into what is going on and
  why. For example if deployments are repeatedly failing,
  then perhaps it is a configuration issue, as opposed to
  a general failure. If a conductor has no resources, then
  the failure, in theory would point back to the conductor
  itself.

Story: 2002980
Task: 42960

Change-Id: Ibfa8ac4878cacd98a43dd4424f6d53021ad91166

1 files changed, 18 insertions, 0 deletions

diff --git a/ironic/db/api.py b/ironic/db/api.py
index 5b71d32bc..77fa054e2 100644
--- a/ironic/db/api.py
+++ b/ironic/db/api.py
@@ -1380,3 +1380,21 @@ class Connection(object, metaclass=abc.ABCMeta):
                          (asc, desc)
         :returns: A list of histories.
         """
+
+    @abc.abstractmethod
+    def query_node_history_records_for_purge(self, conductor_id):
+        """Utility method to identify nodes to clean history records for.
+
+        :param conductor_id: Id value for the conductor to perform this
+                             query on behalf of.
+        :returns: A dictionary with key values of node database ID values
+                  and a list of values associated with the node.
+        """
+
+    @abc.abstractmethod
+    def bulk_delete_node_history_records(self, node_id, limit):
+        """Utility method to bulk delete node history entries.
+
+        :param entires: A list of node history entriy id's to be
+                        queried for deletion.
+        """