ActionController::Parameters deprecation warning: Method size is deprecated and will be removed in Rails 5.1

Question

I recently came across this deprecation warning

DEPRECATION WARNING: Method size is deprecated and will be removed in Rails 5.1, as ActionController::Parameters no longer inherits from hash. Using this deprecated behavior exposes potential security problems. If you continue to use this method you may be creating a security vulnerability in your app that can be exploited.

Params looked like this:

<ActionController::Parameters { "objects" => 
  <ActionController::Parameters {
    "0"=>{"priority"=>"24", "style"=>"three_pictures"}, 
    "1"=>{"priority"=>"24", "style"=>"three_pictures"}, 
    "2"=>{"priority"=>"24", "style"=>"three_pictures"}
} permitted: false> } permitted: false>

And I tried to find the size of objects like this: params[:objects].size

And then I tried the same thing with length and count , which results in the same warning. What would be the work around for this? .keys.length is something that works, but is this the correct way to do it or am I missing something here?

Answer 1

As mentioned in the comments you have to convert params to Hash since in Rails 5 params no longer inherits from Hash . So .size , .length and .count won't work on params directly.

How to convert it to Hash (shorter code may be possible):

permitted_params = params.require(:your_model_name).permit(
  :product_inspirationals => [
    :priority, 
    :style
  ]
).to_h

puts permitted_params[:product_inspirationals].length

Don't know about your model structure so you have to adjust it to your needs.

Answer 2

For hash, you can find the size by .size method.

The problem is not with the size method here, Problem is in the ActionController::Parameters which is not hash,

---

Look at the first line inside ActionController::Parameters

"0"=>{priority"=>"24", "style"=>"three_pictures"}

it should be following as " missing before priority

"0"=>{"priority"=>"24", "style"=>"three_pictures"}

After this .size method should be working