Use new_resource in new action

[EugeneGrigorenko]

• Simplify making new form with prefilled associations
• Is supposed to close this issue Request: Custom-building a new record in controller #220
• Now to have simply override new_resource method instead of new action to init resource associations

P.S. Though, it works as expected on has_one association, when trying to build has_many association it doesn't work. The reason is that select is used on has_many form and only ids get send with the request. And because the record doesn't have an id it gets lost. I'm not sure if it's a bug and should be addressed or not, please let me know what you think.

[nickcharlton]

Hi @EugeneGrigorenko!

Thanks for this! It sounds like we should make sure it still works with a has_many in this PR.

Do you also think you'd be able to add some tests for the feature this gives us, too?

[EugeneGrigorenko]

hi @nickcharlton, sorry for delay
i've investigated a bit and I can say, that has_many works with ids. Like e.g. overriding new_resource like this would initialize customer form with first and last orders selected.

      resource_class.new.tap do |resource|
        resource.order_ids = [::Order.first.id, ::Order.last.id]
      end

To supported creation of has_many via nested forms, I believe, we need to change https://github.com/nickcharlton/administrate-field-nested_has_many

As for tests, I'm not sure what I can test exactly, as, basically that's a one line refactoring so far. It's supposed to being overriden and then it gives new functionality

[nickcharlton]

Okay, cool!

Could you try and confirm if we do indeed to change administrate-field-nested_has_many? If we do, I'll want to coordinate the releases.

[pablobm]

On one hand, this PR looks like a slam dunk to me (provided there's a rebase first). I can't see how it would interfere with anything, and I can see how it's beneficial to have this API.

On the other hand, I'm looking into administrate-field-nested_has_many and I'm having issues making it work at all (unrelated to this PR). Specifically, I'm getting an error when trying to create a School resource in the dummy app... I'm not feeling quite like looking into that one now 😓

@nickcharlton, do you have any thoughts?

[nickcharlton]

I rebased and then merged. We'll worry about nested has many when it's a problem (assuming it is!).

[sedubois]

Is this new_resource method documented somewhere?

[nickcharlton]

I don't believe so, but I might be wrong. Would you be able to do that?

If it doesn't fit anywhere as is, we might want to create an "Administrate Internals" documentation page.

[sedubois]

Sorry @nickcharlton I'm not familiar with this method, maybe someone else knows a bit more?

[nickcharlton]

I don't either! I'll open a new issue to keep track of it.