x/stacktach-sandbox
Code Issues Proposed changes

Callback handlers are now idempotent.

Browse Source 
The sandbox demo now uses a list of callback handlers with
separate trigger and commit phases. Idempotent work should
only be done during the commit() call. Temporary work can
be stored in the callback's 'scratchpad' dictionary until
commit() is called.
This commit is contained in:
Sandy Walsh 2014-08-29 20:12:42 -03:00
parent c988c39988
commit f4839a6b28
1 changed files with 62 additions and 13 deletions
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75
oahu_config.py
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@ -6,25 +6,73 @@ from oahu import pipeline_callback
from oahu import criteria
class Callback(pipeline_callback.PipelineCallback):
def on_trigger(self, stream):
print "Processing", stream
# We determine which operation this is by the first of these we see.
OPERATIONS = [
'compute.instance.shutdown.start',
'compute.instance.delete.start',
'compute.instance.snapshot.start',
'compute.instance.create.start',
'compute.instance.reboot.start',
'compute.instance.rebuild.start',
'compute.instance.resize.start',
'compute.instance.finish_resize.start',
'compute.instance.resize.confirm.start',
'compute.instance.resize.prep.start',
'compute.instance.power_off.start',
'compute.instance.rescue.start',
'compute.instance.unrescue.start',
]
class RequestIdCallback(pipeline_callback.PipelineCallback):
def on_trigger(self, stream, scratchpad):
if not len(stream.events):
return
# Try to guess the operation by the first know event_type ...
operation = None
for e in stream.events:
if e['event_type'] in OPERATIONS:
operation = e['event_type']
break
scratchpad['operation'] = operation
# How long did this operation take?
first = stream.events[0]
last = stream.events[-1]
delta = last['timestamp'] - first['timestamp']
scratchpad['request_id'] = first['_context_request_id']
scratchpad['delta'] = delta
def commit(self, stream, scratchpad):
print "Req: %s %s time delta = %s" % (scratchpad['request_id'],
scratchpad['operation'],
scratchpad['delta'])
class EodExistsCallback(pipeline_callback.PipelineCallback):
def on_trigger(self, stream, scratchpad):
print "EOD-Exists:", stream
#for event in stream.events:
# print event['timestamp'], event['event_type']
def commit(self, stream, scratchpad):
pass
class Config(oahu.config.Config):
def get_driver(self, callback=None):
if not callback:
self.callback = Callback()
else:
self.callback = callback
def get_driver(self):
self.request_id_callback = RequestIdCallback()
self.eod_exists_callback = EodExistsCallback()
# Trigger names have to be consistent across all workers
# (yagi and daemons).
by_request = trigger_definition.TriggerDefinition("request-id",
["_context_request_id", ],
criteria.Inactive(60),
self.callback,
debug=True)
["_context_request_id", ],
criteria.Inactive(60),
[self.request_id_callback,],
debug=True)
# This trigger requires a Trait called "when_date" which is
# the date-only portion of the "when" trait. We will create
@ -34,7 +82,8 @@ class Config(oahu.config.Config):
["payload/instance_id", "audit_bucket"],
criteria.EndOfDayExists(
'compute.instance.exists'),
self.callback, debug=True,
[self.eod_exists_callback,],
debug=True,
dumper=debugging.DetailedDumper())
triggers = [by_request, instance_usage]