Martin Yanchev said over 1 year ago on Bulk Upload with Active Storage :
Hi is anyone else gettingĀ 
ActiveSupport::MessageVerifier::InvalidSignature

The only difference is that I have an Album and this album has_many Image model and this image model has_one attached :file
#image.rb
class Image < ApplicationRecord
  belongs_to :album
  has_one_attached :file
end


#album.rb
class Album < ApplicationRecord
  has_many :images, dependent: :destroy
  accepts_nested_attributes_for :images, allow_destroy: true, reject_if: :all_blank
  has_one_attached :cover_photo


  def self.attributable_params
    [:title,
      :cover_photo,
      images:[],
    ]
  end
end


#the form
<%= form_with url: album_images_uploads_path(@album), multiplart: true   do |form| %>
    <%= form.file_field :file, multiple: true, direct_upload: true %>
    <%= form.submit %>
<% end %>


#images_uploads_controller.rb
class ImagesUploadsController < ApplicationController
  before_action :set_album
  def create
    params[:file].each do |blob|
      @album.images.create(file: blob)
    end
    redirect_to album_path(@album)
  end

  private

  def set_album
    @album = Album.find(params[:album_id])
  end
end


this is what gets send from the form