In T227207: Wikibase JSON output (dumps, Special:EntityData) lacks qualifier hashes we discovered that GenericServices::getCompactBaseDataModelSerializerFactory is used to create entity JSON output for the dumps and Special:EntityData. The function is documented as Factory creating serializers that generate the most compact serialization., but that doesn't seem to be the way it is used currently (we expect hashes in the output for example).
- We should look how/ where this function is used and whether it is appropriate.
- Fix all usages
- The function should be changed to using SerializerFactory::OPTION_SERIALIZE_SNAKS_WITHOUT_HASH again (essentially revert 881780ae6b1f5cacb224efa9fa065599e51bb028)