how to find what all associations have dependent: destroy associated with them from a concern

I am building a soft delete solution a la https://github.com/discourse/discourse/blob/master/app/models/concerns/trashable.rb . Right now I am manually finding which all associated models need to be deleted when a model is deleted and doing it manually in each model which of course is a not a good practice. How do I do it? I don’t want to use a gem, I want to write logic in my own hands.

Hi Aravind,

I am not sure if I understood your question correctly but I will give a
try.
I think you want to delete all associated records with another type of
the Model.

class Body
   has_many: boobs, dependent: :destroy
end

In this instance destroy parameter is responsible for generating/using code

that removes all dependent boob if the body instance is destroyed.

Did I get you right?

The place to start is reflect_on_all_associations:

http://api.rubyonrails.org/classes/ActiveRecord/Reflection/ClassMethods.html#method-i-reflect_on_all_associations

This will give you all the associations defined for the model. You can then request the option you’re interested in thus:


klass.reflect_on_all_associations do |reflection|

if reflection.options[:dependent]

# do something with it

end

end

–Matt Jones