Compruebe si el registro se acaba de destruir en rieles

83

Entonces alli esta

record.new_record?

Para comprobar si algo es nuevo

Necesito comprobar si algo está saliendo.

record = some_magic
record.destroy
record.is_destroyed? # => true

Something like that. I know destroying freezes the object, so frozen? sort of works, but is there something explicitly for this task?

ruby-on-rails ruby activerecord

— Daniel Huckstep
fuente

51

You can do this.

Record.exists?(record)

However that will do a hit on the database which isn't really necessary. The only other solution I know is to do a callback as theIV mentioned.

attr_accessor :destroyed
after_destroy :mark_as_destroyed
def mark_as_destroyed
  self.destroyed = true
end

And then check record.destroyed.

— ryanb
fuente

2

I think some context is helpful here. It depends on why you want to know if an object has been destroyed. If you're doing it as part of a unit test, then the extra hit against the database is fine. If you're doing it as part of the app, then going the second route might be a better bet.

— jerhinesmith

67

This is no longer necessary, use object.destroyed?

— Rob

2

in Rails 4, DEPRECATION WARNING: You are passing an instance of ActiveRecord::Base to exists?. Please pass the id of the object by calling .id.

— Minqi Pan

5

Still need Record.exists? in controller specs, because I can't reload destroyed record to check if it is destroyed?. But if I have instance variable to check with assings, then I can use destroyed?.

— denis.peplin

@Daniel Huckstep, if you are still alive, please, change the accepted answer for the correct one!

— Daniel

202

Just do it:

record.destroyed?

Details are here ActiveRecord::Persistence

— Voldy
fuente

11

This is coming very soon. In the latest Riding Rails post, it says this:

And finally, it's not necessarily BugMash-related, but José Valim - among dozens of other commits - added model.destroyed?. This nifty method will return true only if the instance you're currently looking at has been successfully destroyed.

So there you go. Coming soon!

— Steve Klabnik
fuente

6

While record.destroyed? works fine, and does return true or false, you can also DRY this up a little bit and create the if condition on the line you call destroy on in your controller.

record = Object.find(params[:id])
if record.destroy
  ... happy path
else
  ... sad path
end

Realize this post is a bit late in the game. But should anyone want to discuss this more, i'm game! Side note: I also had an after_destroy validation on my model and while it worked, a separate method for something like this seems like overkill ;)

— DGG
fuente

5

destroying an object doesn't return anything other than a call to freeze (as far as I know) so I think frozen? is your best bet. Your other option is to rescue from ActiveRecord::RecordNotFound if you did something like record.reload.

I think Mike's tactic above could be best, or you could write a wrapper for these cases mentioned if you want to start 'making assumptions'.

Cheers.

— theIV
fuente

I currently just check frozen?, but really I can load something and freeze it for some other purpose, and it would be a lie then... In the current situation, frozen? works fine, but I don't want to rely on it long term.

— Daniel Huckstep

0

Without knowing more of the logic of your app, I think that frozen? is your best bet.

Failing that, you could certainly add a "destroyed" attribute to your models that you trigger in the callbacks and that could be checked against if you want a more precise solution.

— Mike Buckbee
fuente