如何允许数组使用强参数？

Question

I'm actually posting an Array of ids to my Rails API but the array is received as a hash where the keys are the index of the array.

I already try permitting the parameters params.permit(permission_ids: []) and nothing...

User migration

class CreateUsers < ActiveRecord::Migration[5.1]
  def change
    create_table :users do |t|
      t.string :username, null: false
      t.string :email, null: true
      t.integer :language_id, null: false
      t.integer :permission_ids, array: true, default: []
      t.string :password_digest, null: false
      t.timestamps
    end
    add_index :users, :username, unique: true
  end
end

User params method in the controller.

  def user_params
    params.require(:user).permit(:username,
                                 :email,
                                 :language_id,
                                 :password,
                                 :password_confirmation,
                                 permission_ids: [])
  end

How parameters are received

Parameters: {"user"=>{"username"=>"someusername", "email"=>"someemail@question.com", "language_id"=>"2", "permission_ids"=>{"0"=>"1", "1"=>"2", "2"=>"3", "3"=>"4", "4"=>"5", "5"=>"6", "6"=>"7", "7"=>"8", "8"=>"9", "9"=>"10", "10"=>"11", "11"=>"12"}}}

By the way, I'm posting from Vue using Axios.

Answer 1

Can you also update the question with html form that is submitting this data. Issue could be in the form as well.

When you want the form to submit an entry as array, the form attribute should be

user['permission_ids'][]

By this, the html form will understand that the input to permission_ids in the html form, will be submitting an array.

For more info: https://stackoverflow.com/a/45233604/4940278

Answer 2

The way I manage to get the array of ids:

def user_params
    params[:user][:permission_ids] = (params.dig(:user, :permission_ids) || {}).values
    params.require(:user).permit(:username,
                                 :email,
                                 :language_id,
                                 :password,
                                 :password_confirmation,
                                 permission_ids: [])
  end