Add a "register" class decorator for admin.

[Stavros Korokithakis]

The syntax for registering an admin class is a bit unpythonic, so I propose that the admin.site.register method should also have the capability of being used as a decorator.

A simple implementation is below:

def register_admin(model):
    def wrapper(klass):
        admin.site.register(model, klass)
        return klass
    return wrapper

I feel that

@register(MyModel)
class AdminClass:
    pass

is more pythonic than

class AdminClass:
    pass
register(MyModel, AdminClass)

which just screams "decorator".

[BHold]

Added pull request: ​https://github.com/django/django/pull/599

I added a decorator that registers Model/ModelAdmin pairs with AdminSites. I mostly followed how the AdminSite.register method currently does this.

Passes all tests, including those I added.

This is only my 2nd time contributing to the project, and first time writing Sphinx docs, so please let me know if I didn't follow any conventions!

[Stavros Korokithakis]

Why not just reuse admin.site.register? It looks like you reimplemented the method?

[BHold]

Replying to stavros:

Why not just reuse admin.site.register? It looks like you reimplemented the method?

The decorator function should behave a little differently than the normal register method of the Site. For one, it should accept a 'site' argument so that a user can use it with a custom Site model. It also should be able to accept multiple models as arguments that will all be linked to the decorated ModelAdmin class in the Site's registry.

[Stavros Korokithakis]

Sure, but you don't have to reimplement the whole admin.site.register method, you can just wrap it and add the extra functionality needed.

[BHold]

Replying to stavros:

Sure, but you don't have to reimplement the whole admin.site.register method, you can just wrap it and add the extra functionality needed.

True, I pushed up a new commit that does just that! What do you think?

[Stavros Korokithakis]

Much better! I would not have added the "Unsupported arguments" check if I wrote it, just because someone might want to construct a dict with extra stuff and pass it (plus, ignoring kwargs isn't bad for you), but otherwise it looks great to me.

Can someone official chime in? This pull request looks very good.

[BHold]

Replying to stavros:

Much better! I would not have added the "Unsupported arguments" check if I wrote it, just because someone might want to construct a dict with extra stuff and pass it (plus, ignoring kwargs isn't bad for you), but otherwise it looks great to me.

Can someone official chime in? This pull request looks very good.

Yeah, perhaps that Unsupported Arguments check was unneeded, I removed it.

[Rafal Stozek]

I think you should also import this decorator in django/contrib/admin/__init__.py.

[Tim Graham <timograham@…>]

In 98514849dce07acfaa224a90a784bba9d97249e5:

Fixed #19414 -- Added admin registration decorator

Thanks stavros for the suggestion.

[Tim Graham <timograham@…>]

In e23de9e350d716c4d9ebe0b27c9f2752fe1aa543:

Fixed typo in exception message; refs #19414

Thanks Alexey Boriskin for the report.