class Paperclip::Attachment

The Attachment class manages the files for a given attachment. It saves when the model saves, deletes when the model is destroyed, and processes the file upon assignment.

Attributes

convert_options[R]
default_style[R]
instance[R]
interpolator[R]
name[R]
options[R]
post_processing[RW]
queued_for_write[R]
source_file_options[R]
whiny[R]

Public Class Methods

default_options() click to toggle source
# File lib/paperclip/attachment.rb, line 9
def self.default_options
  @default_options ||= {
    :convert_options       => {},
    :default_style         => :original,
    :default_url           => "/:attachment/:style/missing.png",
    :restricted_characters => /[&$+,\/:;=?@<>\[\]\{\}\|\\^~%# ]/,
    :hash_data             => ":class/:attachment/:id/:style/:updated_at",
    :hash_digest           => "SHA1",
    :interpolator          => Paperclip::Interpolations,
    :only_process          => [],
    :path                  => ":rails_root/public:url",
    :preserve_files        => false,
    :processors            => [:thumbnail],
    :source_file_options   => {},
    :storage               => :filesystem,
    :styles                => {},
    :url                   => "/system/:class/:attachment/:id_partition/:style/:filename",
    :url_generator         => Paperclip::UrlGenerator,
    :use_default_time_zone => true,
    :use_timestamp         => true,
    :whiny                 => Paperclip.options[:whiny] || Paperclip.options[:whiny_thumbnails]
  }
end
new(name, instance, options = {}) click to toggle source

Creates an Attachment object. name is the name of the attachment, instance is the ActiveRecord object instance it's attached to, and options is the same as the hash passed to has_attached_file.

Options include:

url - a relative URL of the attachment. This is interpolated using interpolator path - where on the filesystem to store the attachment. This is interpolated using interpolator styles - a hash of options for processing the attachment. See has_attached_file for the details only_process - style args to be run through the post-processor. This defaults to the empty list default_url - a URL for the missing image default_style - the style to use when an argument is not specified e.g. url, path storage - the storage mechanism. Defaults to :filesystem use_timestamp - whether to append an anti-caching timestamp to image URLs. Defaults to true whiny, whiny_thumbnails - whether to raise when thumbnailing fails use_default_time_zone - related to use_timestamp. Defaults to true hash_digest - a string representing a class that will be used to hash URLs for obfuscation hash_data - the relative URL for the hash data. This is interpolated using interpolator hash_secret - a secret passed to the hash_digest convert_options - flags passed to the convert command for processing source_file_options - flags passed to the convert command that controls how the file is read processors - classes that transform the attachment. Defaults to [:thumbnail] preserve_files - whether to keep files on the filesystem when deleting or clearing the attachment. Defaults to false interpolator - the object used to interpolate filenames and URLs. Defaults to Paperclip::Interpolations url_generator - the object used to generate URLs, using the interpolator. Defaults to Paperclip::UrlGenerator

# File lib/paperclip/attachment.rb, line 62
def initialize(name, instance, options = {})
  @name              = name
  @instance          = instance

  options = self.class.default_options.merge(options)

  @options               = options
  @post_processing       = true
  @queued_for_delete     = []
  @queued_for_write      = {}
  @errors                = {}
  @dirty                 = false
  @interpolator          = options[:interpolator]
  @url_generator         = options[:url_generator].new(self, @options)
  @source_file_options   = options[:source_file_options]
  @whiny                 = options[:whiny]

  initialize_storage
end

Public Instance Methods

assign(uploaded_file) click to toggle source

What gets called when you call instance.attachment = File. It clears errors, assigns attributes, and processes the file. It also queues up the previous file for deletion, to be flushed away on save of its host. In addition to form uploads, you can also assign another Paperclip attachment:

new_user.avatar = old_user.avatar
# File lib/paperclip/attachment.rb, line 88
def assign uploaded_file
  ensure_required_accessors!
  file = Paperclip.io_adapters.for(uploaded_file)

  @options[:only_process].map!(&:to_sym)
  self.clear(*@options[:only_process])
  return nil if file.nil?

  @queued_for_write[:original]   = file
  instance_write(:file_name,       cleanup_filename(file.original_filename))
  instance_write(:content_type,    file.content_type.to_s.strip)
  instance_write(:file_size,       file.size)
  instance_write(:fingerprint,     file.fingerprint) if instance_respond_to?(:fingerprint)
  instance_write(:created_at,      Time.now) if has_enabled_but_unset_created_at?
  instance_write(:updated_at,      Time.now)

  @dirty = true

  post_process(*@options[:only_process]) if post_processing

  # Reset the file size if the original file was reprocessed.
  instance_write(:file_size,   @queued_for_write[:original].size)
  instance_write(:fingerprint, @queued_for_write[:original].fingerprint) if instance_respond_to?(:fingerprint)
end
clear(*styles_to_clear) click to toggle source

Clears out the attachment. Has the same effect as previously assigning nil to the attachment. Does NOT save. If you wish to clear AND save, use destroy.

# File lib/paperclip/attachment.rb, line 208
def clear(*styles_to_clear)
  if styles_to_clear.any?
    queue_some_for_delete(*styles_to_clear)
  else
    queue_all_for_delete
    @queued_for_write  = {}
    @errors            = {}
  end
end
content_type() click to toggle source

Returns the #content_type of the file as originally assigned, and lives in the <attachment>_content_type attribute of the model.

# File lib/paperclip/attachment.rb, line 253
def content_type
  instance_read(:content_type)
end
created_at() click to toggle source

Returns the creation time of the file as originally assigned, and lives in the <attachment>_created_at attribute of the model.

# File lib/paperclip/attachment.rb, line 259
def created_at
  if able_to_store_created_at?
    time = instance_read(:created_at)
    time && time.to_f.to_i
  end
end
destroy() click to toggle source

Destroys the attachment. Has the same effect as previously assigning nil to the attachment *and saving*. This is permanent. If you wish to wipe out the existing attachment but not save, use clear.

# File lib/paperclip/attachment.rb, line 221
def destroy
  unless @options[:preserve_files]
    clear
    save
  end
end
dirty?() click to toggle source

Returns true if there are changes that need to be saved.

# File lib/paperclip/attachment.rb, line 192
def dirty?
  @dirty
end
errors() click to toggle source

Returns an array containing the errors on this attachment.

# File lib/paperclip/attachment.rb, line 187
def errors
  @errors
end
file?() click to toggle source

Returns true if a file has been assigned.

# File lib/paperclip/attachment.rb, line 307
def file?
  !original_filename.blank?
end
Also aliased as: present?
fingerprint() click to toggle source

Returns the fingerprint of the file, if one's defined. The fingerprint is stored in the <attachment>_fingerprint attribute of the model.

# File lib/paperclip/attachment.rb, line 247
def fingerprint
  instance_read(:fingerprint)
end
hash_key(style_name = default_style) click to toggle source

Returns a unique hash suitable for obfuscating the URL of an otherwise publicly viewable attachment.

# File lib/paperclip/attachment.rb, line 281
def hash_key(style_name = default_style)
  raise ArgumentError, "Unable to generate hash without :hash_secret" unless @options[:hash_secret]
  require 'openssl' unless defined?(OpenSSL)
  data = interpolate(@options[:hash_data], style_name)
  OpenSSL::HMAC.hexdigest(OpenSSL::Digest.const_get(@options[:hash_digest]).new, @options[:hash_secret], data)
end
instance_read(attr) click to toggle source

Reads the attachment-specific attribute on the instance. See #instance_write for more details.

# File lib/paperclip/attachment.rb, line 331
def instance_read(attr)
  getter = :"#{name}_#{attr}"
  if instance.respond_to?(getter)
    instance.send(getter)
  end
end
instance_respond_to?(attr) click to toggle source

Determines whether the instance responds to this attribute. Used to prevent calculations on fields we won't even store.

# File lib/paperclip/attachment.rb, line 315
def instance_respond_to?(attr)
  instance.respond_to?(:"#{name}_#{attr}")
end
instance_write(attr, value) click to toggle source

Writes the attachment-specific attribute on the instance. For example, #instance_write(:file_name, “me.jpg”) will write “me.jpg” to the instance's “avatar_file_name” field (assuming the attachment is called avatar).

# File lib/paperclip/attachment.rb, line 322
def instance_write(attr, value)
  setter = :"#{name}_#{attr}="
  if instance.respond_to?(setter)
    instance.send(setter, value)
  end
end
original_filename() click to toggle source

Returns the name of the file as originally assigned, and lives in the <attachment>_file_name attribute of the model.

# File lib/paperclip/attachment.rb, line 235
def original_filename
  instance_read(:file_name)
end
path(style_name = default_style) click to toggle source

Returns the path of the attachment as defined by the :path option. If the file is stored in the filesystem the path refers to the path of the file on disk. If the file is stored in S3, the path is the “key” part of the URL, and the :bucket option refers to the S3 bucket.

# File lib/paperclip/attachment.rb, line 149
def path(style_name = default_style)
  path = original_filename.nil? ? nil : interpolate(path_option, style_name)
  path.respond_to?(:unescape) ? path.unescape : path
end
present?()
Alias for: file?
processors() click to toggle source
# File lib/paperclip/attachment.rb, line 176
def processors
  processing_option = @options[:processors]

  if processing_option.respond_to?(:call)
    processing_option.call(instance)
  else
    processing_option
  end
end
reprocess!(*style_args) click to toggle source

This method really shouldn't be called that often. It's expected use is in the paperclip:refresh rake task and that's it. It will regenerate all thumbnails forcefully, by reobtaining the original file and going through the post-process again.

# File lib/paperclip/attachment.rb, line 292
def reprocess!(*style_args)
  saved_only_process, @options[:only_process] = @options[:only_process], style_args
  begin
    assign(self)
    save
    instance.save
  rescue Errno::EACCES => e
    warn "#{e} - skipping file."
    false
  ensure
    @options[:only_process] = saved_only_process
  end
end
save() click to toggle source

Saves the file, if there are no errors. If there are, it flushes them to the instance's errors and returns false, cancelling the save.

# File lib/paperclip/attachment.rb, line 198
def save
  flush_deletes unless @options[:keep_old_files]
  flush_writes
  @dirty = false
  true
end
size() click to toggle source

Returns the size of the file as originally assigned, and lives in the <attachment>_file_size attribute of the model.

# File lib/paperclip/attachment.rb, line 241
def size
  instance_read(:file_size) || (@queued_for_write[:original] && @queued_for_write[:original].size)
end
styles() click to toggle source
# File lib/paperclip/attachment.rb, line 163
def styles
  if @options[:styles].respond_to?(:call) || @normalized_styles.nil?
    styles = @options[:styles]
    styles = styles.call(self) if styles.respond_to?(:call)

    @normalized_styles = styles.dup
    styles.each_pair do |name, options|
      @normalized_styles[name.to_sym] = Paperclip::Style.new(name.to_sym, options.dup, self)
    end
  end
  @normalized_styles
end
time_zone() click to toggle source

The time zone to use for timestamp interpolation. Using the default time zone ensures that results are consistent across all threads.

# File lib/paperclip/attachment.rb, line 275
def time_zone
  @options[:use_default_time_zone] ? Time.zone_default : Time.zone
end
to_s(style_name = default_style) click to toggle source

Alias to url

# File lib/paperclip/attachment.rb, line 155
def to_s style_name = default_style
  url(style_name)
end
updated_at() click to toggle source

Returns the last modified time of the file as originally assigned, and lives in the <attachment>_updated_at attribute of the model.

# File lib/paperclip/attachment.rb, line 268
def updated_at
  time = instance_read(:updated_at)
  time && time.to_f.to_i
end
uploaded_file() click to toggle source

Returns the uploaded file if present.

# File lib/paperclip/attachment.rb, line 229
def uploaded_file
  instance_read(:uploaded_file)
end
url(style_name = default_style, options = {}) click to toggle source

Returns the public URL of the attachment with a given style. This does not necessarily need to point to a file that your Web server can access and can instead point to an action in your app, for example for fine grained security; this has a serious performance tradeoff.

Options:

timestamp - Add a timestamp to the end of the URL. Default: true. escape - Perform URI escaping to the URL. Default: true.

Global controls (set on has_attached_file):

interpolator - The object that fills in a URL pattern's variables. default_url - The image to show when the attachment has no image. url - The URL for a saved image. url_generator - The object that generates a URL. Default: Paperclip::UrlGenerator.

As mentioned just above, the object that generates this URL can be passed in, for finer control. This object must respond to two methods:

+#new(Paperclip::Attachment, options_hash)+ +#for(style_name, options_hash)+

# File lib/paperclip/attachment.rb, line 135
def url(style_name = default_style, options = {})
  default_options = {:timestamp => @options[:use_timestamp], :escape => true}

  if options == true || options == false # Backwards compatibility.
    @url_generator.for(style_name, default_options.merge(:timestamp => options))
  else
    @url_generator.for(style_name, default_options.merge(options))
  end
end

Private Instance Methods

able_to_store_created_at?() click to toggle source

Check if attachment database table has a #created_at field

# File lib/paperclip/attachment.rb, line 468
def able_to_store_created_at?
  @instance.respond_to?("#{name}_created_at".to_sym)
end
after_flush_writes() click to toggle source

called by storage after the writes are flushed and before @queued_for_writes is cleared

# File lib/paperclip/attachment.rb, line 452
def after_flush_writes
   @queued_for_write.each do |style, file|
     file.close unless file.closed?
     file.unlink if file.respond_to?(:unlink) && file.path.present? && File.exist?(file.path)
   end
end
cleanup_filename(filename) click to toggle source
# File lib/paperclip/attachment.rb, line 459
def cleanup_filename(filename)
  if @options[:restricted_characters]
    filename.gsub(@options[:restricted_characters], '_')
  else
    filename
  end
end
has_enabled_but_unset_created_at?() click to toggle source

Check if attachment database table has a #created_at field which is not yet set

# File lib/paperclip/attachment.rb, line 473
def has_enabled_but_unset_created_at?
  able_to_store_created_at? && !instance_read(:created_at)
end
path_option() click to toggle source
# File lib/paperclip/attachment.rb, line 340
def path_option
  @options[:path].respond_to?(:call) ? @options[:path].call(self) : @options[:path]
end
queue_some_for_delete(*styles) click to toggle source
# File lib/paperclip/attachment.rb, line 426
def queue_some_for_delete(*styles)
  @queued_for_delete += styles.uniq.map do |style|
    path(style) if exists?(style)
  end.compact
end