Can't retrieve file from S3 with Rails Active Storage - ruby-on-rails

Question

I am trying to upload a photo to S3 using Rails Active Storage.
I can attach a photo:
user.photo.attach(io: File.open('spec/images/filename.png'), filename: 'filename.png')
I can save the user and I can get the photo service url and see it in the browser, and in my bucket:
user.photo.service_url
However, if I restart my console and try to get the service url, I receive the following error:
Module::DelegationError (service_url delegated to attachment, but attachment is nil)
Here are my bucket settings:
storage.yml:
amazon:
service: S3
access_key_id: <%= Rails.application.credentials.dig(:aws, :access_key_id) %>
secret_access_key: <%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
region: us-east-2
bucket: <%= Rails.application.credentials.dig(:aws, :bucket) %>
application.rb:
config.active_storage.service = :amazon
user.rb:
has_one_attached :photo
I am also having trouble using public: true in the storage.yml file.
I receive the following error if I try to set the config:
ArgumentError (Cannot load `Rails.config.active_storage.service`:)
invalid configuration option `:public'
amazon:
service: S3
access_key_id: <%= Rails.application.credentials.dig(:aws, :access_key_id) %>
secret_access_key: <%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
region: us-east-2
bucket: <%= Rails.application.credentials.dig(:aws, :bucket) %>
public: true

Answer 1

I also wanted to upload my files to AWS S3, and have them publically available.
I ran into this issue as well and found the following:
ArgumentError (Cannot load `Rails.config.active_storage.service`:)
invalid configuration option `:public'
comes from this file in the aws-sdk-ruby gem. As per the error message, the aws-sdk-ruby gem does not support the public: true option.
I used the following work-around (special thanks to this article):
I updated my storage.yml to:
public_amazon:
service: S3
access_key_id: some_key
secret_access_key: some_secret
bucket: some-bucket-name
region: some-region
upload:
acl: "public-read"
The above sets the uploaded file permissions to be public.
Retrieve the public URL like this:
user.photo.attach(params[:file])
url = user.photo.service.send(:object_for, user.photo.key).public_url