Summary

DRIVERS-2322 will likely restrict the tests in change-streams.yml to only run against replicasets. Running those tests against sharded clusters results in a number of failures for tests that expect a particular order of events (extra drop and write events are observed in at least a couple drivers). We should add sharded topologies back into the test-file-level runOnRequirements and investigate the cause of the failures.

Motivation

Who is the affected end user?

Users of change streams against sharded topologies.

How does this affect the end user?

In not testing change streams against sharded topologies, driver devs are missing test coverage for the behavior of change streams with sharded topologies, which should be supported behavior.

How likely is it that this problem or use case will occur?

There are many users of change streams that are interacting with sharded clusters.

If the problem does occur, what are the consequences and how severe are they?

If we do not test against sharded topologies, we may miss bugs introduced in change streams changes.

Is this issue urgent?

Somewhat.

Is this ticket required by a downstream team?

No.

Is this ticket only for tests?

Yes.