# File activestorage/lib/active_storage/attached/many.rb, line 30
def attach(*attachables)
  if record.persisted? && !record.changed?
    record.update(name => blobs + attachables.flatten)
  else
    record.public_send("#{name}=", (change&.attachables || blobs) + attachables.flatten)
  end
end

Attaches one or more attachables to the record.

If the record is persisted and unchanged, the attachments are saved to the database immediately. Otherwise, they'll be saved to the DB when the record is next saved.

document.images.attach(params[:images]) # Array of ActionDispatch::Http::UploadedFile objects
document.images.attach(params[:signed_blob_id]) # Signed reference to blob from direct upload
document.images.attach(io: File.open("/path/to/racecar.jpg"), filename: "racecar.jpg", content_type: "image/jpg")
document.images.attach([ first_blob, second_blob ])

# File activestorage/lib/active_storage/attached/many.rb, line 45
def attached?
  attachments.any?
end

Returns true if any attachments has been made.

class Gallery < ActiveRecord::Base
  has_many_attached :photos
end

Gallery.new.photos.attached? # => false

# File activestorage/lib/active_storage/attached/many.rb, line 11
def attachments
  change.present? ? change.attachments : record.public_send("#{name}_attachments")
end

Returns all the associated attachment records.

All methods called on this proxy object that aren't listed here will automatically be delegated to attachments.

# File activestorage/lib/active_storage/attached/many.rb, line 16
def blobs
  change.present? ? change.blobs : record.public_send("#{name}_blobs")
end

Returns all attached blobs.

# File activestorage/lib/active_storage/attached/many.rb, line 50
def detach
  attachments.delete_all if attached?
end

Deletes associated attachments without purging them, leaving their respective blobs in place.

# File activestorage/lib/active_storage/attached/many.rb, line 60
    

Directly purges each associated attachment (i.e. destroys the blobs and attachments and deletes the files on the service).

# File activestorage/lib/active_storage/attached/many.rb, line 64
  

Purges each associated attachment through the queuing system.