web_connectivity measurement with no DNS queries

[fortuna]

Describe the bug
This measurement has an empty test_keys.queries field:
https://explorer.ooni.org/measurement/20201030T030550Z_webconnectivity_RU_41661_n1_wYIBb6tHu6wrFbqS?input=http%3A%2F%2Fvoice.yahoo.jajah.com%2F

Expected behavior
The field should contain a list with at least one query.

[fortuna]

I found another example: https://explorer.ooni.org/measurement/20201115T194951Z_webconnectivity_IR_12880_n1_xqETuH8J04j66IzK?input=http%3A%2F%2Fmoqavemat.ir%2F'

moqavemat.ir returns SERVFAIL when I query.
Perhaps no queries means some currently unspecified error that should be made explicit.

[bassosimone]

This is when the legacy probe fails to perform the lookup and does not include any query in the measurement. I have just tested with probe-engine. We correctly insert the queries in this case. I will not close this issue because it documents an existing data quality bug that existed in the past. Thank you for researching this!