commit 6bc25fa98e82327dd2f1fd54ecb4af7bb9d6e93c
author Edwin Kempin <ekempin@google.com> Thu Mar 25 12:39:03 2021 +0100
committer Edwin Kempin <ekempin@google.com> Wed Mar 31 14:56:17 2021 +0200
tree e9805b4bd761e64a237acd5b6ab0b73f5f622a3d
parent 50350c19eaec106c5f45a487708d218b17338932

BatchUpdate: Cache ChangeData instances that are created for indexing

When a change is updated it needs to be reindexed. For reindexing a
change a ChangeData instance is created and the submit rules are
executed. In the postUpdate step of BatchUpdate a ChangaData instance
for the updated change is needed again to send a change-updated event.
For the event the change is formatted as JSON which triggers the submit
rules a second time.

ChangeData already caches the result of running submit rules, this means
if we can avoid that ChangeData is instantiated twice, we can avoid that
the submit rules are executed twice. This is important since executing
submit rules is rather expensive.

To avoid instantiating ChangeData twice we now cache the ChangeData
instances that were created for indexing and make them available to the
postUpdate step via the context that is provided to the postUpdate step.

With this change the postUpdate steps do not use the provided ChangeData
instances yet, so that ChangeData is still instantiated a second time
for sending the event. This will be addressed in a follow-up change.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I415d745deb148ea12b1c1f4ed06cc695b7355d90