Returns the attachment definitions defined by each call to has_attached_file.
# File lib/paperclip.rb, line 211 def attachment_definitions self.attachment_definitions end
has_attached_file
gives the class it is called on an attribute
that maps to a file. This is typically a file stored somewhere on the
filesystem and has been uploaded by a user. The attribute returns a Paperclip::Attachment object which handles the
management of that file. The intent is to make the attachment as much like
a normal attribute. The thumbnails will be created when the new file is
assigned, but they will not be saved until
save
is called on the record. Likewise, if the attribute is
set to nil
is called on it, the attachment will
not be deleted until save
is called. See the
Paperclip::Attachment documentation for more
specifics. There are a number of options you can set to change the behavior
of a Paperclip attachment:
url
: The full URL of where the attachment is publically
accessible. This can just as easily point to a directory served directly
through Apache as it can to an action that can control permissions. You can
specify the full domain and path, but usually just an absolute path is
sufficient. The leading slash must be included manually
for absolute paths. The default value is
“/system/:class/:attachment/:id_partition/:style/:filename”. See
Paperclip::Attachment#interpolate for more information on variable
interpolaton.
:url => "/:class/:attachment/:id/:style_:filename" :url => "http://some.other.host/stuff/:class/:id_:extension"
default_url
: The URL that will be returned if there is no
attachment assigned. This field is interpolated just as the url is. The
default value is “/:attachment/:style/missing.png”
has_attached_file :avatar, :default_url => "/images/default_:style_avatar.png" User.new.avatar_url(:small) # => "/images/default_small_avatar.png"
styles
: A hash of thumbnail styles and their geometries. You
can find more about geometry strings at the ImageMagick website (www.imagemagick.org/script/command-line-options.php#resize).
Paperclip also adds the “#” option (e.g.
“50x50#”), which will resize the image to fit maximally inside the
dimensions and then crop the rest off (weighted at the center). The default
value is to generate no thumbnails.
default_style
: The thumbnail style that will be used by
default URLs. Defaults to original
.
has_attached_file :avatar, :styles => { :normal => "100x100#" }, :default_style => :normal user.avatar.url # => "/avatars/23/normal_me.png"
keep_old_files
: Keep the existing attachment files (original +
resized) from being automatically deleted when an attachment is cleared or
updated. Defaults to false
.#
whiny
: Will raise an error if Paperclip cannot post_process an uploaded file
due to a command line error. This will override the global setting for this
attachment. Defaults to true.
convert_options
: When creating thumbnails, use this free-form
options array to pass in various convert command options. Typical options
are “-strip” to remove all Exif data from the image (save space for
thumbnails and avatars) or “-depth 8” to specify the bit depth of the
resulting conversion. See ImageMagick convert documentation for more
options: (www.imagemagick.org/script/convert.php)
Note that this option takes a hash of options, each of which correspond to
the style of thumbnail being generated. You can also specify :all as a key,
which will apply to all of the thumbnails being generated. If you specify
options for the :original, it would be best if you did not specify
destructive options, as the intent of keeping the original around is to
regenerate all the thumbnails when requirements change.
has_attached_file :avatar, :styles => { :large => "300x300", :negative => "100x100" } :convert_options => { :all => "-strip", :negative => "-negate" }
NOTE: While not deprecated yet, it is not recommended to specify options this way. It is recommended that :convert_options option be included in the hash passed to each :styles for compatibility with future versions. NOTE: Strings supplied to :convert_options are split on space in order to undergo shell quoting for safety. If your options require a space, please pre-split them and pass an array to :convert_options instead.
storage
: Chooses the storage backend where the files will be
stored. The current choices are :filesystem, :fog and :s3. The default is
:filesystem. Make sure you read the documentation for Paperclip::Storage::Filesystem, Paperclip::Storage::Fog and Paperclip::Storage::S3 for backend-specific
options.
It's also possible for you to dynamically define your interpolation string for :url, :default_url, and :path in your model by passing a method name as a symbol as a argument for your #has_attached_file definition:
class Person has_attached_file :avatar, :default_url => :default_url_by_gender private def default_url_by_gender "/assets/avatars/default_#{gender}.png" end end
# File lib/paperclip.rb, line 171 def has_attached_file(name, options = {}) include InstanceMethods if attachment_definitions.nil? self.attachment_definitions = {} else self.attachment_definitions = self.attachment_definitions.dup end attachment_definitions[name] = Paperclip::AttachmentOptions.new(options) Paperclip.classes_with_attachments << self.name Paperclip.check_for_url_clash(name,attachment_definitions[name][:url],self.name) after_save :save_attached_files before_destroy :prepare_for_destroy after_destroy :destroy_attached_files define_paperclip_callbacks :post_process, :"#{name}_post_process" define_method name do |*args| a = attachment_for(name) (args.length > 0) ? a.to_s(args.first) : a end define_method "#{name}=" do |file| attachment_for(name).assign(file) end define_method "#{name}?" do attachment_for(name).file? end validates_each(name) do |record, attr, value| attachment = record.attachment_for(name) attachment.send(:flush_errors) end end