[Do Not Merge] v20.x

[arthurschreiber]

Description

This pull request is used to track which backports we've done against the upstream v20 release.

Related Issue(s)

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

[Copilot]

Pull Request Overview

This PR updates the Vitess tablet gateway and keyspace event watcher to gate startup based on keyspace consistency and buffering conditions during reparent operations. Key changes include:

• Replacing the legacy PrimaryIsNotServing API with the more descriptive ShouldStartBufferingForTarget in both production and test code.
• Introducing WaitForConsistentKeyspaces to ensure keyspaces are processed before allowing primary tablet queries.
• Updating srvtopo discovery functions to return both targets and keyspaces.

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
go/vt/vtgate/tabletgateway_test.go	Added a new test (TestWithRetry) that validates the new retry and buffering behavior.
go/vt/vtgate/tabletgateway_flaky_test.go	Updated tests to use ShouldStartBufferingForTarget instead of PrimaryIsNotServing.
go/vt/vtgate/tabletgateway.go	Replaced API calls to use the new keyspace event buffering logic and await keyspace consistency.
go/vt/srvtopo/discover_test.go	Renamed tests to use FindAllTargetsAndKeyspaces and assert on the returned keyspaces list.
go/vt/srvtopo/discover.go	Updated function signature and documentation to return both targets and keyspaces.
go/vt/discovery/keyspace_events_test.go	Adjusted tests to validate the new ShouldStartBufferingForTarget API and its expectations.
go/vt/discovery/keyspace_events.go	Renamed PrimaryIsNotServing to ShouldStartBufferingForTarget and added WaitForConsistentKeyspaces.

Comments suppressed due to low confidence (1)

go/vt/discovery/keyspace_events.go:749

• [nitpick] The compound boolean expression is complex; consider refactoring it into multiple well-named boolean variables or adding inline comments to improve readability and maintainability.

return state.currentPrimary, !state.serving && !ks.consistent && state.externallyReparented != 0 && state.currentPrimary != nil

[Copilot]

WaitForConsistentKeyspaces uses a fixed sleep interval in a loop which may lead to long waits if keyspaces never become consistent; consider introducing a configurable timeout or maximum iteration limit to avoid potential resource waste.

Suggested change

	func (kew *KeyspaceEventWatcher) WaitForConsistentKeyspaces(ctx context.Context, ksList []string) error {
	// We don't want to change the original keyspace list that we receive so we clone it
	// before we empty it elements down below.
	keyspaces := slices.Clone(ksList)
	func (kew *KeyspaceEventWatcher) WaitForConsistentKeyspaces(ctx context.Context, ksList []string, timeout time.Duration) error {
	// We don't want to change the original keyspace list that we receive so we clone it
	// before we empty it elements down below.
	keyspaces := slices.Clone(ksList)
	timeoutChan := time.After(timeout)

[github-actions]

This PR is being marked as stale because it has been open for 30 days with no activity. To rectify, you may do any of the following:

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If no action is taken within 7 days, this PR will be closed.

[github-actions]

This PR was closed because it has been stale for 7 days with no activity.

[github-actions]

This PR is being marked as stale because it has been open for 30 days with no activity. To rectify, you may do any of the following:

• Push additional commits to the associated branch.
• Remove the stale label.
• Add a comment indicating why it is not stale.

If no action is taken within 7 days, this PR will be closed.

[github-actions]

This PR was closed because it has been stale for 7 days with no activity.