Lazy loaded fields do not block save and cause unexpected modificiations

[moonrail]

NetBox version

v3.0.2

Python version

3.9

Steps to Reproduce

1. Create e.g. a Device
2. Edit the Device, save it as fast as possible (Edit -> directly to Save)
3. Inspect error messages, that tell you, you should choose a Site, Device-Type and Device-Role

The time required to "wait" before saving anything is depending on the time lazy fields require to load their data.
So more data causes more time margin for this error to cause issues and increases its real life applicance.

Expected Behavior

A save without any changes should not omit data of the current instance of the model.

Observed Behavior

The POST is done before lazy loading is finished and seems to send null-values for the unfinished fields.
On NetBox instances with a lot of e.g. Sites, VLANs or else - anything that is loaded dynamically/loaded lazy, this issue becomes more and more apparent.

As you can see in the screenshot attached, the lazy loading of my local dev env (with nearly no data in it) took long enough to reproduce this error:

Note: I have a simple CustomValidator with tenant required, therefore is Tenant also noted as required in screenshot.

[DanSheps]

loading time increase in 3.0.2 with lazy loading

This has nothing to do with the existing issue. Please open a new issue.

[DanSheps]

v3.0.2

This cannot be reproduced in v3.0.3.

Please upgrade and try to reproduce this. If you cannot please close the issue.

[moonrail]

It's reproducable in 3.0.3.

Please see the following screenshot:

1. API-Requests for lazy loaded fields do not finish before "Save" is triggered and are aborted. Note that Requests to Tenants, Device-Types and Sites are not completed.
2. POST is executed and returns visible errors. As Devices cannot be created without a Device-Type or Site, this indicates, that some information of the edited Device is not sent with the POST request on "Save". The Device has values for all errored fields, so it has to have something to do with the Edit-Form not being loaded fully. If I wait a little bit longer before saving, no such issue occurs.

Even if the regular user should most of the time not run into this issue, this has a lot of creep potential, where one single API request of a lazy loaded field is taking longer than the User needs and the edited object is nulling the before existing value, unbeknownest to the User.

[DanSheps]

I was finally able to reproduce this. Maybe this is something @thatmattlove can look at, however I don't know if we can classify this as a bug as it looks like no data is saved.

[jeremystretch]

Is there a reason we need to pre-populate the choices for all these fields (other than any single initially-selected choice), as opposed to populating them on-demand when the user expands a selection field?

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. NetBox is governed by a small group of core maintainers which means not all opened issues may receive direct feedback. Please see our contributing guide.

[DanSheps]

I think the solution is to block form submission until all fields are loaded.