[bug] ObjectLocation admin doesn't work in readonly mode

[nemesifier]

When a user has only view permission, the map doesn't work because the JS fails (it was not tested in this scenario).

[devkapilbansal]

When a user has only view permission, the map doesn't work because the JS fails (it was not tested in this scenario).

I don't think it is due to the JS. If a user doesn't have change permissions, then these fields are not shown in ObjectLocation admin

I also found something in Django admin where we might found a possible fix 👇
https://github.com/django/django/blob/cf79f92abee2ff5fd4fdcc1a124129a9773805b8/django/contrib/admin/options.py#L674

[pandafy]

I also found something in Django admin where we might found a possible fix
https://github.com/django/django/blob/cf79f92abee2ff5fd4fdcc1a124129a9773805b8/django/contrib/admin/options.py#L674

That only affects ModelAdmin and not InlineAdmin.

I created a simple demo project with our use case and also posted in django-users mailing list for help.

Also, django-leaflet does not render map for view only permissions: makinacorpus/django-leaflet#85

[DragnEmperor]

I also found something in Django admin where we might found a possible fix
https://github.com/django/django/blob/cf79f92abee2ff5fd4fdcc1a124129a9773805b8/django/contrib/admin/options.py#L674

That only affects ModelAdmin and not InlineAdmin.

I created a simple demo project with our use case and also posted in django-users mailing list for help.

Also, django-leaflet does not render map for view only permissions: makinacorpus/django-leaflet#85

@pandafy i looked into it and it seems that for view only permissions, AdminReadonlyField is used and it looksup the fields in the instance, and hence does not uses the 'initial_data' which are used by BoundFields.
https://github.com/django/django/blob/ef62a3a68c9d558486145a42c0d71ea9a76add9e/django/contrib/admin/helpers.py#L265

I believe this can be solved by annotations or manually bypassing the permission checks to let BoundFields render and then setting the readonly and disabled attribute

[nemesifier]

@DragnEmperor if you can try that locally and let us know if it works we'll be happy to fix this!

[DragnEmperor]

Cool! Working on it.

[DragnEmperor]

@nemesifier I tried it locally and got the map to render, but i think it is rendering slowly. Shall I open a PR for this, will need your guidance if i am approaching this correctly or not.