Class: ActiveStorage::Attached::One

Inherits:
ActiveStorage::Attached show all
Defined in:
activestorage/lib/active_storage/attached/one.rb

Overview

Representation of a single attachment to a model.

Instance Attribute Summary

Attributes inherited from ActiveStorage::Attached

#name, #record

Instance Method Summary collapse

Methods inherited from ActiveStorage::Attached

#initialize

Constructor Details

This class inherits a constructor from ActiveStorage::Attached

Instance Method Details

#attach(attachable) ⇒ Object

Attaches an attachable to the record.

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

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/jpeg")
person.avatar.attach(avatar_blob) # ActiveStorage::Blob object

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# File 'activestorage/lib/active_storage/attached/one.rb', line 56

def attach(attachable)
  if record.persisted? && !record.changed?
    record.public_send("#{name}=", attachable)
    if record.save
      record.public_send("#{name}")
    else
      false
    end
  else
    record.public_send("#{name}=", attachable)
  end
end

#attached?Boolean

Returns true if an attachment has been made.

class User < ApplicationRecord
  has_one_attached :avatar
end

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

Returns:

  • (Boolean)

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# File 'activestorage/lib/active_storage/attached/one.rb', line 76

def attached?
  attachment.present?
end

#attachmentObject

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.


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# File 'activestorage/lib/active_storage/attached/one.rb', line 31

def attachment
  change.present? ? change.attachment : record.public_send("#{name}_attachment")
end

#blank?Boolean

Returns true if an attachment is not attached.

class User < ApplicationRecord
  has_one_attached :avatar
end

User.new.avatar.blank? # => true

Returns:

  • (Boolean)

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# File 'activestorage/lib/active_storage/attached/one.rb', line 42

def blank?
  !attached?
end

#detachObject

:method: detach

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


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# File 'activestorage/lib/active_storage/attached/one.rb', line 23

delegate :detach, to: :detach_one

#purgeObject

:method: purge

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


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# File 'activestorage/lib/active_storage/attached/one.rb', line 11

delegate :purge, to: :purge_one

#purge_laterObject

:method: purge_later

Purges the attachment through the queuing system.


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# File 'activestorage/lib/active_storage/attached/one.rb', line 17

delegate :purge_later, to: :purge_one