Reopen: Bulk import prefixes with associated VLAN not working when multiple VLANs with the same vid exist. #18582

[jeroendev-one]

NetBox Edition

NetBox Community

NetBox Version

v4.4.2

Python Version

3.10

Steps to Reproduce

The issue seems to be returning here. When importing the prefixes bulk below I get the following error:

Record 1 vlan: "1" is not a unique value for this field; multiple objects were found

prefix;status;vlan_site;vlan;scope_type;scope_id;description
10.11.0.0/22;active;LOC02-MGMT;1;dcim.site;5;LOC02-MGMT

We have multiple sites with the same VLAN id, we re-use them same as the existing issue. However, it doesn't seem to be using the field 'vlan_site' to check whether the VLAN is unique for this one.

Expected Behavior

Import the prefixes and assign VLAN based on VLAN site and not only ID.

Observed Behavior

Unique constraint error.

[bctiemann]

Linking the previous PR for reference.

It's not clear to me why this previous fix would have addressed the issue of enforcing uniqueness across the combined vlan+vlan_site rather than just on the vlan field; this error is being raised from CSVModelChoiceField.to_python which has no knowledge of any other fields, so any place in the code that tries to render that value will run into that error.

I'm trying to find another example of a NetBoxModelImportForm where multiple fields are used for uniqueness checking but I'm coming up blank. I'm sure there are some to use as reference though.