Summary

The prose tests 1-8 in the SRV polling test readme are not implemented in the C driver.

The readme notes that manual testing is acceptable where mocking DNS records is not practical:

However, it might be possible to mock changes to DNS SRV records such that automated testing is doable. In any case, the following tests should be executed, either manually, or programmatically.

However, CDRIVER-4048 introduces a way to mock DNS results with _mongoc_topology_set_rr_resolver. This can be used to implement prose tests 1-8.

Motivation

A bug in SRV polling could result in client applications not properly updating the host list when DNS SRV records change. Note that there have been severe problems with SRV polling before. CDRIVER-3614 is a bug resulting in SRV polling not occurring at all.

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

SRV polling behavior changed as recent as the 1.19.0 release for load balancer support: CDRIVER-4048. If SRV polling behavior changes again, that risks the possibility that the tests are not run manually.

Is this issue urgent?

No

Is this ticket required by a downstream team?

No

Is this ticket only for tests?

Yes