> so where would the logic of "apply if changed" be placed?
In the latest iteration of this branch our "apply if change logic" will require
some followup work.
I think we need a branch that will decompose get_data into the following
separate methods:
1. ds.detect() - speedy/low-cost python logic performs ds-identify determine
if the environment is not a match for this datasource so it can get out fast
2. ds.crawl_metadata(): perform a read-only walk (not affecting the datasource
caches) of all related instance data sources returning a dict
3. ds.get_data() renamed to ds.process_data(crawled_data):
a. will take crawled_metadata dictionary which will be processed and
persisted as instance attributes metadata, vendordata, userdata.
b. write instance-data.json
c. cache crawled_data as ds._crawled_data for future comparison by
metadata_changed method
4. ds.metadata_changed(crawled_data): compares crawled_data to internal cached
crawled_data returning a list of keys which changed content
update_metadata will then look like this:
process_data
if supported_events:
if hasattr(self, 'detect'):
if not ds.detect():
return False
crawled_data = self.crawl_metadata()
if self.metadata_changed(crawled_data):
result = self.process_data(crawled_data)
--
https://code.launchpad.net/~chad.smith/cloud-init/+git/cloud-init/+merge/348000
Your team cloud-init commiters is requested to review the proposed merge of
~chad.smith/cloud-init:feature/maintain-network-on-boot into cloud-init:master.
_______________________________________________
Mailing list: https://launchpad.net/~cloud-init-dev
Post to : [email protected]
Unsubscribe : https://launchpad.net/~cloud-init-dev
More help : https://help.launchpad.net/ListHelp
