What is the correct way to update images with has_many_attached in Rails 6

Question

I have a Rails 6 app that uses Active Storage to store multiple images to a model (Activity) with has_many_attached.

I don't understand how to append extra images instead of replacing the existing images. When I upload images the first time they save correctly. However, when I update the record, and I add a new image, the previous images are replaced by the new image. In Rails 5 the new image would be appended without replacing the previously saved images.

How do I append a new image instead of replacing the previous images?

I have an Activity model that has the following:

has_many_attached :images

In the form I have:

<%= f.file_field :images, multiple: true %>

In the controller I have the following:

def update
  @activity = Activity.find(params[:id])

  if @activity.update(activity_params)
    flash[:success] = "Saved"
    redirect_to activity_path(@activity)
  else
    flash[:error] = "Not saved"
    redirect_to edit_activity_path(@activity)
  end
end

private

  def activity_params
    params.require(:activity).permit(:name, images:[])
  end

here is a similar question https://stackoverflow.com/questions/58282845/rails-6-active-storage-could-not-find-or-build-blob-expected-attachable-got — don_Bigote, Jan 18 '20 at 21:57

don_Bigote · Accepted Answer · 2020-02-01T06:07:27.670

19

This is the solution that I have now:

Add this to the update action:

if params[:activity][:images].present?
  params[:activity][:images].each do |image|
  activity.images.attach(image)
end

So, the entire update action looks like this:

def update
  if activity.update(activity_params)
    if params[:activity][:images].present?
      params[:activity][:images].each do |image|
        activity.images.attach(image)
      end
    end
    flash[:success] = 'Updated!'
    respond_with activity, location: activity_path(activity)
  else
    flash[:error] = 'Not updated'
    respond_with activity, location: activity_path(activity)
  end
end

And remove this from permitted params:

images:[]

edited Feb 01 '20 at 06:07

answered Jan 20 '20 at 19:30

don_Bigote

896
7
33

How could the create action be set up? – don_Bigote Feb 01 '20 at 06:11
just to complement a little with some information, if you change `params[:activity][:images]` to `activity_params[:images] ` it will not work – gcs_dev Oct 03 '20 at 13:27
1

A bit late to the party but assuming you're on Rails 6 this seems to be the culprit: https://stackoverflow.com/questions/61933070/how-to-edit-multiple-attached-images-using-activestorage-has-many-attached-in – stratis Nov 02 '20 at 12:02

score 2 · Answer 2 · answered Apr 02 '23 at 18:36

2

This happens cause assigning to attachments declared with has_many_attached since Rails 6.0 replaces any existing attachments by default.

Details:

So, in Rails 6.0+ you need to add this line to your environment config (config/environments/development.rb, etc.):
config.active_storage.replace_on_assign_to_many = false
After app restart previously added attachments won't be replaced.

answered Apr 02 '23 at 18:36

Max Berdnikau

33
1
1
6

Alternatively, call `attach()` rather than assigning, as in the accepted answer. – Code-Apprentice Apr 02 '23 at 18:42
⚠️ DEPRECATION WARNING: config.active_storage.replace_on_assign_to_many is deprecated and will be removed in Rails 7.1 – Iwan B. May 02 '23 at 21:29

Sumra Yasmin · Answer 3 · 2020-01-20T05:14:20.067

-5

Try selecting multiple files like this https://i.stack.imgur.com/EqaU7.png If it works then you will need to select all previous images while uploading new one which does not sound good. You may like to use nesting forms.

edited Jan 20 '20 at 05:14

answered Jan 20 '20 at 05:06

Sumra Yasmin

9
1
2

The question here is: How do I append a new image instead of replacing the previous images? In Rails 6 the way to update multiple images for a given record has changed since Rails 5. Based on your answer you may not be familiar with this issue. – don_Bigote Jan 20 '20 at 19:32

What is the correct way to update images with has_many_attached in Rails 6

3 Answers3

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