diff options
Diffstat (limited to 'activestorage/lib/active_storage/attached/model.rb')
| -rw-r--r-- | activestorage/lib/active_storage/attached/model.rb | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/activestorage/lib/active_storage/attached/model.rb b/activestorage/lib/active_storage/attached/model.rb new file mode 100644 index 0000000000..ae7f0685f2 --- /dev/null +++ b/activestorage/lib/active_storage/attached/model.rb @@ -0,0 +1,140 @@ +# frozen_string_literal: true + +module ActiveStorage + # Provides the class-level DSL for declaring an Active Record model's attachments. + module Attached::Model + extend ActiveSupport::Concern + + class_methods do + # Specifies the relation between a single attachment and the model. + # + # class User < ActiveRecord::Base + # has_one_attached :avatar + # end + # + # There is no column defined on the model side, Active Storage takes + # care of the mapping between your records and the attachment. + # + # To avoid N+1 queries, you can include the attached blobs in your query like so: + # + # User.with_attached_avatar + # + # Under the covers, this relationship is implemented as a +has_one+ association to a + # ActiveStorage::Attachment record and a +has_one-through+ association to a + # ActiveStorage::Blob record. These associations are available as +avatar_attachment+ + # and +avatar_blob+. But you shouldn't need to work with these associations directly in + # most circumstances. + # + # The system has been designed to having you go through the ActiveStorage::Attached::One + # proxy that provides the dynamic proxy to the associations and factory methods, like +attach+. + # + # If the +:dependent+ option isn't set, the attachment will be purged + # (i.e. destroyed) whenever the record is destroyed. + def has_one_attached(name, dependent: :purge_later) + generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1 + def #{name} + @active_storage_attached_#{name} ||= ActiveStorage::Attached::One.new("#{name}", self) + end + + def #{name}=(attachable) + attachment_changes["#{name}"] = + if attachable.nil? + ActiveStorage::Attached::Changes::DeleteOne.new("#{name}", self) + else + ActiveStorage::Attached::Changes::CreateOne.new("#{name}", self, attachable) + end + end + CODE + + has_one :"#{name}_attachment", -> { where(name: name) }, class_name: "ActiveStorage::Attachment", as: :record, inverse_of: :record, dependent: :destroy + has_one :"#{name}_blob", through: :"#{name}_attachment", class_name: "ActiveStorage::Blob", source: :blob + + scope :"with_attached_#{name}", -> { includes("#{name}_attachment": :blob) } + + after_save { attachment_changes[name.to_s]&.save } + + after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) } + + ActiveRecord::Reflection.add_attachment_reflection( + self, + name, + ActiveRecord::Reflection.create(:has_one_attached, name, nil, { dependent: dependent }, self) + ) + end + + # Specifies the relation between multiple attachments and the model. + # + # class Gallery < ActiveRecord::Base + # has_many_attached :photos + # end + # + # There are no columns defined on the model side, Active Storage takes + # care of the mapping between your records and the attachments. + # + # To avoid N+1 queries, you can include the attached blobs in your query like so: + # + # Gallery.where(user: Current.user).with_attached_photos + # + # Under the covers, this relationship is implemented as a +has_many+ association to a + # ActiveStorage::Attachment record and a +has_many-through+ association to a + # ActiveStorage::Blob record. These associations are available as +photos_attachments+ + # and +photos_blobs+. But you shouldn't need to work with these associations directly in + # most circumstances. + # + # The system has been designed to having you go through the ActiveStorage::Attached::Many + # proxy that provides the dynamic proxy to the associations and factory methods, like +#attach+. + # + # If the +:dependent+ option isn't set, all the attachments will be purged + # (i.e. destroyed) whenever the record is destroyed. + def has_many_attached(name, dependent: :purge_later) + generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1 + def #{name} + @active_storage_attached_#{name} ||= ActiveStorage::Attached::Many.new("#{name}", self) + end + + def #{name}=(attachables) + attachment_changes["#{name}"] = + if attachables.nil? || Array(attachables).none? + ActiveStorage::Attached::Changes::DeleteMany.new("#{name}", self) + else + ActiveStorage::Attached::Changes::CreateMany.new("#{name}", self, attachables) + end + end + CODE + + has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment", inverse_of: :record, dependent: :destroy do + def purge + each(&:purge) + reset + end + + def purge_later + each(&:purge_later) + reset + end + end + has_many :"#{name}_blobs", through: :"#{name}_attachments", class_name: "ActiveStorage::Blob", source: :blob + + scope :"with_attached_#{name}", -> { includes("#{name}_attachments": :blob) } + + after_save { attachment_changes[name.to_s]&.save } + + after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) } + + ActiveRecord::Reflection.add_attachment_reflection( + self, + name, + ActiveRecord::Reflection.create(:has_many_attached, name, nil, { dependent: dependent }, self) + ) + end + end + + def attachment_changes #:nodoc: + @attachment_changes ||= {} + end + + def reload(*) #:nodoc: + super.tap { @attachment_changes = nil } + end + end +end |