Rating: depend =>: destroy

Question

In Rails 2.2.2 (ruby 1.8.7-p72), I would like to evaluate the impact of destroying an object before it actually executes. That is, I would like to be able to generate a list of all the objects that will be affected by: depend =>: destroy (through object associations). The real problem I'm trying to solve is to provide the user with a list of everything that will be deleted and confirm their action.

Can someone recommend a good way to do this? I just started to learn ActiveRecord :: Associations, but I have not achieved much success.

Update. In my particular case, I have different levels of objects (A → B → C).

Answer 1

This should help you get started ... Obviously, you will have to configure it, but it lists all the association names that depend on the destruction in the BlogEntry class:

BlogEntry.reflect_on_all_associations.map do |association| if association.options[:dependent] == :destroy # do something here... association.name end end.compact => [:taggings, :comments] 

Answer 2

Just manually maintain a list of related objects with dependent destruction (maybe it doesn't matter what you need to do anyway), and then have named_scopes for each to pull the included objects for display.

Answer 3

I would say that, as mentioned, there is a way to display the affected entries to the user, then there are two buttons / links, one of which is deleted, possibly with confirmation for the user who asks if they checked the other link, which is a list of all records that they will influence.

Then, if you want to be sure that you can also do a soft deletion by marking them as deleted in the database, rather than deleting them, which may come in handy, I don’t know how you can handle this automatic dependent deletion, possibly with act_as_paranoid or some kind of self-catalyzed version with a parent model callback.

Answer 4

I recently wrote a simple Rails plugin that solves this problem.
Check it out on github: http://github.com/murbanski/affected_on_destroy/tree