How can I get rails parameters to accept an array of strings?

Question

I have a model which has an array of strings.

class A < ApplicationRecord
  serialize :vals, Array
end

How can I get my controller

class AController < ApplicationController
  def create
    par = params.require(:a).permit(:vals)
    ...
  end
end

to accept an array of inputs?

Sebastián Palma · Accepted Answer · 2017-07-12 01:27:16Z

2

Try declaring it as an array of values:

def create
  par = params.require(:a).permit(vals: [])
  ...
end

answered Jul 12, 2017 at 1:27

Sebastián Palma

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4 Comments

rails does not like this if I have more than one parameter e.g. params.require(:a).permit(:b,vals:[])

How's it? Rails doesn't like it?

Apparently, this only happens if you put vals:[] in the middle of two parameters.

Yes, you're right, it must be added as the last value, not the first one, nor in the middle, although can be if it's the only one.