module ActiveStorage::Attached::Model
Active Storage Attached Model
Provides the class-level DSL for declaring an Active Record model’s attachments.
Public instance methods
*_attachments
Returns the attachments for the has_many_attached.
Gallery.last.photos_attachments
has_many_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
Specifies the relation between multiple attachments and the model.
class Gallery < ApplicationRecord
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.
The :dependent option defaults to :purge_later. This means the attachments will be purged (i.e. destroyed) in the background whenever the record is destroyed. If an ActiveJob::Backend queue adapter is not set in the application set it to purge instead.
If you need the attachment to use a service which differs from the globally configured one, pass the :service option. For example:
class Gallery < ActiveRecord::Base
has_many_attached :photos, service: :s3
end
:service can also be specified as a proc, and it will be called with the model instance:
class Gallery < ActiveRecord::Base
has_many_attached :photos, service: ->(gallery) { gallery.personal? ? :personal_s3 : :s3 }
end
If you need to enable strict_loading to prevent lazy loading of attachments, pass the :strict_loading option. You can do:
class Gallery < ApplicationRecord
has_many_attached :photos, strict_loading: true
end
Note: Active Storage relies on polymorphic associations, which in turn store class names in the database. When renaming classes that use has_many, make sure to also update the class names in the active_storage_attachments.record_type polymorphic type column of the corresponding rows.
Source code GitHub
# File activestorage/lib/active_storage/attached/model.rb, line 206
def has_many_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
ActiveStorage::Blob.validate_service_configuration(service, self, name) unless service.is_a?(Proc)
generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1
# frozen_string_literal: true
def #{name}
@active_storage_attached ||= {}
@active_storage_attached[:#{name}] ||= ActiveStorage::Attached::Many.new("#{name}", self)
end
def #{name}=(attachables)
attachables = Array(attachables).compact_blank
pending_uploads = attachment_changes["#{name}"].try(:pending_uploads)
attachment_changes["#{name}"] = if attachables.none?
ActiveStorage::Attached::Changes::DeleteMany.new("#{name}", self)
else
ActiveStorage::Attached::Changes::CreateMany.new("#{name}", self, attachables, pending_uploads: pending_uploads)
end
end
CODE
has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment", inverse_of: :record, dependent: :destroy, strict_loading: strict_loading
has_many :"#{name}_blobs", through: :"#{name}_attachments", class_name: "ActiveStorage::Blob", source: :blob, strict_loading: strict_loading
scope :"with_attached_#{name}", -> {
if ActiveStorage.track_variants
includes("#{name}_attachments": { blob: {
variant_records: { image_attachment: :blob },
preview_image_attachment: { blob: { variant_records: { image_attachment: :blob } } }
} })
else
includes("#{name}_attachments": :blob)
end
}
after_save { attachment_changes[name.to_s]&.save }
after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) }
reflection = ActiveRecord::Reflection.create(
:has_many_attached,
name,
nil,
{ dependent: dependent, service_name: service },
self
)
yield reflection if block_given?
ActiveRecord::Reflection.add_attachment_reflection(self, name, reflection)
endhas_one_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
Specifies the relation between a single attachment and the model.
class User < ApplicationRecord
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.
The :dependent option defaults to :purge_later. This means the attachment will be purged (i.e. destroyed) in the background whenever the record is destroyed. If an ActiveJob::Backend queue adapter is not set in the application set it to purge instead.
If you need the attachment to use a service which differs from the globally configured one, pass the :service option. For example:
class User < ActiveRecord::Base
has_one_attached :avatar, service: :s3
end
:service can also be specified as a proc, and it will be called with the model instance:
class User < ActiveRecord::Base
has_one_attached :avatar, service: ->(user) { user.in_europe_region? ? :s3_europe : :s3_usa }
end
If you need to enable strict_loading to prevent lazy loading of attachment, pass the :strict_loading option. You can do:
class User < ApplicationRecord
has_one_attached :avatar, strict_loading: true
end
Note: Active Storage relies on polymorphic associations, which in turn store class names in the database. When renaming classes that use has_one_attached, make sure to also update the class names in the active_storage_attachments.record_type polymorphic type column of the corresponding rows.
Source code GitHub
# File activestorage/lib/active_storage/attached/model.rb, line 106
def has_one_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
ActiveStorage::Blob.validate_service_configuration(service, self, name) unless service.is_a?(Proc)
generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1
# frozen_string_literal: true
def #{name}
@active_storage_attached ||= {}
@active_storage_attached[:#{name}] ||= ActiveStorage::Attached::One.new("#{name}", self)
end
def #{name}=(attachable)
attachment_changes["#{name}"] =
if attachable.nil? || attachable == ""
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, strict_loading: strict_loading
has_one :"#{name}_blob", through: :"#{name}_attachment", class_name: "ActiveStorage::Blob", source: :blob, strict_loading: strict_loading
scope :"with_attached_#{name}", -> {
if ActiveStorage.track_variants
includes("#{name}_attachment": { blob: {
variant_records: { image_attachment: :blob },
preview_image_attachment: { blob: { variant_records: { image_attachment: :blob } } }
} })
else
includes("#{name}_attachment": :blob)
end
}
after_save { attachment_changes[name.to_s]&.save }
after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) }
reflection = ActiveRecord::Reflection.create(
:has_one_attached,
name,
nil,
{ dependent: dependent, service_name: service },
self
)
yield reflection if block_given?
ActiveRecord::Reflection.add_attachment_reflection(self, name, reflection)
endwith_attached_*
Includes the attached blobs in your query to avoid N+1 queries.
If ActiveStorage.track_variants is enabled, it will also include the variants record and their attached blobs.
User.with_attached_avatar
Use the plural form for has_many_attached:
Gallery.with_attached_photos
Source code GitHub
# File activestorage/lib/active_storage/attached/model.rb, line 54
class_methods do
# Specifies the relation between a single attachment and the model.
#
# class User < ApplicationRecord
# 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+.
#
# The +:dependent+ option defaults to +:purge_later+. This means the attachment will be
# purged (i.e. destroyed) in the background whenever the record is destroyed.
# If an ActiveJob::Backend queue adapter is not set in the application set it to
# +purge+ instead.
#
# If you need the attachment to use a service which differs from the globally configured one,
# pass the +:service+ option. For example:
#
# class User < ActiveRecord::Base
# has_one_attached :avatar, service: :s3
# end
#
# +:service+ can also be specified as a proc, and it will be called with the model instance:
#
# class User < ActiveRecord::Base
# has_one_attached :avatar, service: ->(user) { user.in_europe_region? ? :s3_europe : :s3_usa }
# end
#
# If you need to enable +strict_loading+ to prevent lazy loading of attachment,
# pass the +:strict_loading+ option. You can do:
#
# class User < ApplicationRecord
# has_one_attached :avatar, strict_loading: true
# end
#
# Note: Active Storage relies on polymorphic associations, which in turn store class names in the database.
# When renaming classes that use <tt>has_one_attached</tt>, make sure to also update the class names in the
# <tt>active_storage_attachments.record_type</tt> polymorphic type column of
# the corresponding rows.
def has_one_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
ActiveStorage::Blob.validate_service_configuration(service, self, name) unless service.is_a?(Proc)
generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1
# frozen_string_literal: true
def #{name}
@active_storage_attached ||= {}
@active_storage_attached[:#{name}] ||= ActiveStorage::Attached::One.new("#{name}", self)
end
def #{name}=(attachable)
attachment_changes["#{name}"] =
if attachable.nil? || attachable == ""
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, strict_loading: strict_loading
has_one :"#{name}_blob", through: :"#{name}_attachment", class_name: "ActiveStorage::Blob", source: :blob, strict_loading: strict_loading
scope :"with_attached_#{name}", -> {
if ActiveStorage.track_variants
includes("#{name}_attachment": { blob: {
variant_records: { image_attachment: :blob },
preview_image_attachment: { blob: { variant_records: { image_attachment: :blob } } }
} })
else
includes("#{name}_attachment": :blob)
end
}
after_save { attachment_changes[name.to_s]&.save }
after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) }
reflection = ActiveRecord::Reflection.create(
:has_one_attached,
name,
nil,
{ dependent: dependent, service_name: service },
self
)
yield reflection if block_given?
ActiveRecord::Reflection.add_attachment_reflection(self, name, reflection)
end
# Specifies the relation between multiple attachments and the model.
#
# class Gallery < ApplicationRecord
# 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+.
#
# The +:dependent+ option defaults to +:purge_later+. This means the attachments will be
# purged (i.e. destroyed) in the background whenever the record is destroyed.
# If an ActiveJob::Backend queue adapter is not set in the application set it to
# +purge+ instead.
#
# If you need the attachment to use a service which differs from the globally configured one,
# pass the +:service+ option. For example:
#
# class Gallery < ActiveRecord::Base
# has_many_attached :photos, service: :s3
# end
#
# +:service+ can also be specified as a proc, and it will be called with the model instance:
#
# class Gallery < ActiveRecord::Base
# has_many_attached :photos, service: ->(gallery) { gallery.personal? ? :personal_s3 : :s3 }
# end
#
# If you need to enable +strict_loading+ to prevent lazy loading of attachments,
# pass the +:strict_loading+ option. You can do:
#
# class Gallery < ApplicationRecord
# has_many_attached :photos, strict_loading: true
# end
#
# Note: Active Storage relies on polymorphic associations, which in turn store class names in the database.
# When renaming classes that use <tt>has_many</tt>, make sure to also update the class names in the
# <tt>active_storage_attachments.record_type</tt> polymorphic type column of
# the corresponding rows.
def has_many_attached(name, dependent: :purge_later, service: nil, strict_loading: false)
ActiveStorage::Blob.validate_service_configuration(service, self, name) unless service.is_a?(Proc)
generated_association_methods.class_eval <<-CODE, __FILE__, __LINE__ + 1
# frozen_string_literal: true
def #{name}
@active_storage_attached ||= {}
@active_storage_attached[:#{name}] ||= ActiveStorage::Attached::Many.new("#{name}", self)
end
def #{name}=(attachables)
attachables = Array(attachables).compact_blank
pending_uploads = attachment_changes["#{name}"].try(:pending_uploads)
attachment_changes["#{name}"] = if attachables.none?
ActiveStorage::Attached::Changes::DeleteMany.new("#{name}", self)
else
ActiveStorage::Attached::Changes::CreateMany.new("#{name}", self, attachables, pending_uploads: pending_uploads)
end
end
CODE
has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment", inverse_of: :record, dependent: :destroy, strict_loading: strict_loading
has_many :"#{name}_blobs", through: :"#{name}_attachments", class_name: "ActiveStorage::Blob", source: :blob, strict_loading: strict_loading
scope :"with_attached_#{name}", -> {
if ActiveStorage.track_variants
includes("#{name}_attachments": { blob: {
variant_records: { image_attachment: :blob },
preview_image_attachment: { blob: { variant_records: { image_attachment: :blob } } }
} })
else
includes("#{name}_attachments": :blob)
end
}
after_save { attachment_changes[name.to_s]&.save }
after_commit(on: %i[ create update ]) { attachment_changes.delete(name.to_s).try(:upload) }
reflection = ActiveRecord::Reflection.create(
:has_many_attached,
name,
nil,
{ dependent: dependent, service_name: service },
self
)
yield reflection if block_given?
ActiveRecord::Reflection.add_attachment_reflection(self, name, reflection)
end
end