openstack/deb-aodh
Code Issues Proposed changes

Add a specialized Event Type model and db table

Browse Source 
As the events API gets fleshed out and more robust,
it will become increasingly necessary to ensure that the
database schema modeling events has the ability to quickly
retrieve a list of event types. With the current schema
having a foreign key from event to unique_name (the
monolithic generic string key lookup table), in order to
get a simple list of event types, one needs to do the following:

SELECT DISTINCT e.unique_name FROM event;

Not only is this inefficient, but the readability of the
model and database schema suffers from the generalization of
the unique name field relationship. With this patch, a new
event_type table is added to the schema to allow for quick
and easy lookups of event types like so:

SELECT id, desc FROM event_type;

This will lead to future ability to categorize
event types with ease. Instead of adding columns to the
monolithic unique_name table, we would only need to add a foreign
key relationship to the new event_type table tying the event_type
to a future event_type_class table...

This patch also renames "event_name" to "event_type" everywhere
to avoid confusion.

Change-Id: I6e630ec534f16ba1bb9370d1859ae7640fc6b05b
Partial-Bug: 1211015
This commit is contained in:
Jay Pipes
2013-11-20 16:09:00 -06:00
committed by John Herndon
parent 3ea0b70db0
commit 545200dd22
12 changed files with 298 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files

63
ceilometer/storage/impl_sqlalchemy.py
View File

@@ -849,15 +849,33 @@ class Connection(base.Connection):
values[value_map[trait_model.dtype]] = value
return models.Trait(name, event, trait_model.dtype, **values)
@staticmethod
def _get_or_create_event_type(event_type, session=None):
"""Here, we check to see if an event type with the supplied
name already exists. If not, we create it and return the record.
This may result in a flush.
"""
if session is None:
session = sqlalchemy_session.get_session()
with session.begin(subtransactions=True):
et = session.query(models.EventType).filter(
models.EventType.desc == event_type).first()
if not et:
et = models.EventType(event_type)
session.add(et)
session.flush()
return et
def _record_event(self, session, event_model):
"""Store a single Event, including related Traits.
"""
with session.begin(subtransactions=True):
unique = self._get_or_create_unique_name(event_model.event_name,
session=session)
event_type = self._get_or_create_event_type(event_model.event_type,
session=session)
generated = utils.dt_to_decimal(event_model.generated)
event = models.Event(event_model.message_id, unique, generated)
event = models.Event(event_model.message_id, event_type, generated)
session.add(event)
new_traits = []
@@ -867,7 +885,7 @@ class Connection(base.Connection):
session.add(t)
new_traits.append(t)
# Note: we don't flush here, explicitly (unless a new uniquename
# Note: we don't flush here, explicitly (unless a new event_type
# does it). Otherwise, just wait until all the Events are staged.
return (event, new_traits)
@@ -900,7 +918,9 @@ class Connection(base.Connection):
return problem_events
def get_events(self, event_filter):
"""Return an iterable of model.Event objects.
"""Return an iterable of model.Event objects. The event model objects
have their Trait model objects available -- filtered by any traits
in the event_filter.
:param event_filter: EventFilter instance
"""
@@ -909,17 +929,18 @@ class Connection(base.Connection):
end = utils.dt_to_decimal(event_filter.end)
session = sqlalchemy_session.get_session()
with session.begin():
event_query_filters = [models.Event.generated >= start,
models.Event.generated <= end]
sub_query = session.query(models.Event.id)\
.join(models.Trait, models.Trait.event_id == models.Event.id)
.join(models.EventType,
models.Event.event_type_id == models.EventType.id)\
.join(models.Trait,
models.Trait.event_id == models.Event.id)\
.filter(models.Event.generated >= start,
models.Event.generated <= end)
if event_filter.event_name:
event_name = self._get_unique(session, event_filter.event_name)
event_query_filters.append(
models.Event.unique_name == event_name)
sub_query = sub_query.filter(*event_query_filters)
if event_filter.event_type:
event_type = event_filter.event_type
sub_query = sub_query\
.filter(models.EventType.desc == event_type)
event_models_dict = {}
if event_filter.traits:
@@ -943,11 +964,19 @@ class Connection(base.Connection):
else:
# Pre-populate event_models_dict to cover Events without traits
events = session.query(models.Event)\
.filter(*event_query_filters)
.filter(models.Event.generated >= start)\
.filter(models.Event.generated <= end)
if event_filter.event_type:
events = events\
.join(models.EventType,
models.EventType.id ==
models.Event.event_type_id)\
.filter(models.EventType.desc ==
event_filter.event_type)
for db_event in events.all():
generated = utils.decimal_to_dt(db_event.generated)
api_event = api_models.Event(db_event.message_id,
db_event.unique_name.key,
db_event.event_type.desc,
generated, [])
event_models_dict[db_event.id] = api_event
@@ -962,7 +991,7 @@ class Connection(base.Connection):
if not event:
generated = utils.decimal_to_dt(trait.event.generated)
event = api_models.Event(trait.event.message_id,
trait.event.unique_name.key,
trait.event.event_type.desc,
generated, [])
event_models_dict[trait.event_id] = event
value = trait.get_value()