app/models/active_storage/attachment.rb
require "active_storage/blob"
require "active_storage/patches/delegation"
require "strong_parameters" if Rails.version < '4.0'
# Attachments associate records with blobs. Usually that's a one record-many blobs relationship,
# but it is possible to associate many different records with the same blob. If you're doing that,
# you'll want to declare with `has_one/many_attached :thingy, dependent: false`, so that destroying
# any one record won't destroy the blob as well. (Then you'll need to do your own garbage collecting, though).
class ActiveStorage::Attachment < ActiveRecord::Base
self.table_name = "active_storage_attachments"
attr_protected if defined?(attr_protected)
include ActiveModel::ForbiddenAttributesProtection if defined?(ActiveModel::ForbiddenAttributesProtection)
belongs_to :record, polymorphic: true
belongs_to :blob, class_name: "ActiveStorage::Blob"
delegate_missing_to :blob
# Purging an attachment will purge the blob (delete the file on the service, then destroy the record)
# and then destroy the attachment itself.
def purge
blob.purge
destroy
end
# Purging an attachment means purging the blob, which means talking to the service, which means
# talking over the internet. Whenever you're doing that, it's a good idea to put that work in a job,
# so it doesn't hold up other operations. That's what #purge_later provides.
def purge_later
ActiveStorage::PurgeAttachmentWorker.perform_async(self.id)
end
end