Missing file field in Nested Attributes - ruby-on-rails

Question

I'm using paperclip in nested attributes and I'm not sure what I'm missing. The view on the form is missing the file upload option.
Form
<%= form_with(model: news, local: true, html: { multipart: true } ) do |form| %>
<%= form.fields_for :images do |img| %>
<%= img.file_field :img, multiple: true %>
<% end%>
<% end %>
Models
class News < ApplicationRecord
has_many :images, dependent: :destroy
accepts_nested_attributes_for :images, allow_destroy: true
end
class Image < ApplicationRecord
belongs_to :news
has_attached_file :img, :styles => { :show => "600x600>" }, size: { less_than: 2.megabytes }
validates_attachment_content_type :img, :content_type => ["image/jpg", "image/jpeg", "image/gif", "image/png"]
end
Controller
class NewsController < ApplicationController
def new
#news = News.new
#news.images.build
end
def create
#news = News.new(news_params)
respond_to do |format|
if #news.save
format.html { redirect_to #news, notice: 'News was successfully created.' }
format.json { render :show, status: :created, location: #news }
else
format.html { render :new }
format.json { render json: #news.errors, status: :unprocessable_entity }
end
end
end
private
def set_news
#news = News.find(params[:id])
end
def news_params
params.require(:news).permit(:title, :description, :category, images_attributes: [:id, :img, :news_id, :_destroy])
end
end
If I change :images to :image in the form the field appears, but then gives an error on submission:
Unpermitted parameter: :image

Answer 1

In your case, you need to explicitly pass a record_object to the fields_for
<%= form.fields_for :images, #news.images.build do |img| %>
<%= img.file_field :img, multiple: true %>
<% end%>
Also in order to send multiple values for img, it should be an array in the permitted params. You should change the news_params to below
def news_params
params.require(:news).permit(:title, :description, :category, images_attributes: [:id, :news_id, :_destroy, img: []])
end