how to permit an array with strong parameters

Question

I have a functioning Rails 3 app that uses has_many :through associations which is not, as I remake it as a Rails 4 app, letting me save ids from the associated model in the

Answer 1

If you want to permit an array of hashes(or an array of objects from the perspective of JSON)

params.permit(:foo, array: [:key1, :key2])

2 points to notice here:

1. array should be the last argument of the permit method.
2. you should specify keys of the hash in the array, otherwise you will get an error Unpermitted parameter: array, which is very difficult to debug in this case.