class ActiveStorage::Attached::One

Parent:: ActiveStorage::Attached

Representation of a single attachment to a model.

Public Instance Methods

attach(attachable) Show source

# File activestorage/lib/active_storage/attached/one.rb, line 22
def attach(attachable)
  blob_was = blob if attached?
  blob = create_blob_from(attachable)

  unless blob == blob_was
    transaction do
      detach
      write_attachment build_attachment(blob: blob)
    end

    blob_was.purge_later if blob_was && dependent == :purge_later
  end
end

Associates a given attachment with the current record, saving it to the database.

person.avatar.attach(params[:avatar]) # ActionDispatch::Http::UploadedFile object
person.avatar.attach(params[:signed_blob_id]) # Signed reference to blob from direct upload
person.avatar.attach(io: File.open("/path/to/face.jpg"), filename: "face.jpg", content_type: "image/jpg")
person.avatar.attach(avatar_blob) # ActiveStorage::Blob object

attached?() Show source

# File activestorage/lib/active_storage/attached/one.rb, line 43
def attached?
  attachment.present?
end

Returns true if an attachment has been made.

class User < ActiveRecord::Base
  has_one_attached :avatar
end

User.new.avatar.attached? # => false

attachment() Show source

# File activestorage/lib/active_storage/attached/one.rb, line 12
def attachment
  record.public_send("#{name}_attachment")
end

Returns the associated attachment record.

You don't have to call this method to access the attachment's methods as they are all available at the model level.

detach() Show source

# File activestorage/lib/active_storage/attached/one.rb, line 48
def detach
  if attached?
    attachment.destroy
    write_attachment nil
  end
end

Deletes the attachment without purging it, leaving its blob in place.

purge() Show source

# File activestorage/lib/active_storage/attached/one.rb, line 57
def purge
  if attached?
    attachment.purge
    write_attachment nil
  end
end

Directly purges the attachment (i.e. destroys the blob and attachment and deletes the file on the service).

purge_later() Show source

# File activestorage/lib/active_storage/attached/one.rb, line 65
def purge_later
  if attached?
    attachment.purge_later
  end
end

Purges the attachment through the queuing system.