This change completes the circular dependency refactor.
The principal change is that queue items may now include
more than one change simultaneously in the case of circular
dependencies.
In dependent pipelines, the two-phase reporting process is
simplified because it happens during processing of a single
item.
In independent pipelines, non-live items are still used for
linear depnedencies, but multi-change items are used for
circular dependencies.
Previously changes were enqueued recursively and then
bundles were made out of the resulting items. Since we now
need to enqueue entire cycles in one queue item, the
dependency graph generation is performed at the start of
enqueing the first change in a cycle.
Some tests exercise situations where Zuul is processing
events for old patchsets of changes. The new change query
sequence mentioned in the previous paragraph necessitates
more accurate information about out-of-date patchsets than
the previous sequence, therefore the Gerrit driver has been
updated to query and return more data about non-current
patchsets.
This change is not backwards compatible with the existing
ZK schema, and will require Zuul systems delete all pipeline
states during the upgrade. A later change will implement
a helper command for this.
All backwards compatability handling for the last several
model_api versions which were added to prepare for this
upgrade have been removed. In general, all model data
structures involving frozen jobs are now indexed by the
frozen job's uuid and no longer include the job name since
a job name no longer uniquely identifies a job in a buildset
(either the uuid or the (job name, change) tuple must be
used to identify it).
Job deduplication is simplified and now only needs to
consider jobs within the same buildset.
The fake github driver had a bug (fakegithub.py line 694) where
it did not correctly increment the check run counter, so our
tests that verified that we closed out obsolete check runs
when re-enqueing were not valid. This has been corrected, and
in doing so, has necessitated some changes around quiet dequeing
when we re-enqueue a change.
The reporting in several drivers has been updated to support
reporting information about multiple changes in a queue item.
Change-Id: I0b9e4d3f9936b1e66a08142fc36866269dc287f1
Depends-On: https://review.opendev.org/907627
1f026bd49c