[Telemetry TABLES!] Changing performance mode changes sort order of request unexpectedly

[jvigliotta]

Summary

Changing the performance mode on Telemetry Tables will incorrectly swap the sort order of the outgoing request.

Expected vs Current Behavior

Should keep the current order or default to descending.

Steps to Reproduce

1. Change the performance mode on a telemetry table while viewing the network tab for the request
2. Note the order in the request url, then change the mode again and note the order has changed

Impact Check List

• Data loss or misrepresented data? (with duplicate timestamps, the order can be different)
• Regression? Did this used to work or has it always been broken?
• Is there a workaround available?
• Does this impact a critical component?
• Is this just a visual bug with no functional impact?
• Does this block the execution of e2e tests?
• Does this have an impact on Performance?

Additional Information

Related to VIPERGC-424

[davetsay]

not fixed. changing sort order is not re-requesting so when you toggle from desc to asc, and then click the performance mode toggle, the request will still query in desc.

[charlesh88]

10/4/24: Still not fixed. Toggling from unlimited to limited should requery but doesn't; this is fixed by #7863. BUT: changing sort order from desc to asc then toggling performance always uses desc as the sort argument.

[akhenry]

Note that #7863 fixes stable insertion into tables, but DOES NOT fix the issue where tables in limited mode are not re-querying when sort order is changed.

[jvigliotta]

Testing

• open the network tab
• view an immutable object in a table (can be a dictionary endpoint)
• note the request order param (default is order=desc)
• change the sort order of a column, then change the mode of the telemetry table to trigger another request
• note the request order param and make sure it has changed (desc to asc or asc to desc)
• next, view the table in "Limited" mode
• now change the sort order of a column
• make sure a new request is sent out
• now change the table to unlimited mode
• change the sort order
• make sure no new request was made

[akhenry]

@charlesh88 to test

[charlesh88]

Testathon 2024-10-10: verified not fixed. Toggling the sort method on the Timestamp column now properly preserves that sort method when toggling limited/unlimited, but sorting on another column (like Value) and toggling performance reverts sorting to the Timestamp column.

[akhenry]

ok, so in the current implementation, Yamcs only sorts by timestamp (it's a time-series database). This behavior is probably not unusual in time-series databases.

Limited mode (aka performance mode) relies on the back-end being able to return us a sorted, limited, subset of results. In this case it literally can't, so we can't support sorting by anything other than timestamp in limited mode right now.