Representation of a single attachment to a model.

Methods

Instance Public methods

attach(attachable)

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
📝 Source code 
# 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
🔎 See on GitHub

attached?()

Returns true if an attachment has been made.

class User < ActiveRecord::Base
  has_one_attached :avatar
end

User.new.avatar.attached? # => false
📝 Source code 
# File activestorage/lib/active_storage/attached/one.rb, line 43
    def attached?
      attachment.present?
    end
🔎 See on GitHub

attachment()

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.

📝 Source code 
# File activestorage/lib/active_storage/attached/one.rb, line 12
    def attachment
      record.public_send("#{name}_attachment")
    end
🔎 See on GitHub

detach()

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

📝 Source code 
# File activestorage/lib/active_storage/attached/one.rb, line 48
    def detach
      if attached?
        attachment.destroy
        write_attachment nil
      end
    end
🔎 See on GitHub

purge()

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

📝 Source code 
# File activestorage/lib/active_storage/attached/one.rb, line 57
    def purge
      if attached?
        attachment.purge
        write_attachment nil
      end
    end
🔎 See on GitHub

purge_later()

Purges the attachment through the queuing system.

📝 Source code 
# File activestorage/lib/active_storage/attached/one.rb, line 65
    def purge_later
      if attached?
        attachment.purge_later
      end
    end
🔎 See on GitHub