Class: Paperclip::Attachment

Inherits:
Object
  • Object
show all
Defined in:
lib/paperclip/attachment.rb

Overview

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.

Instance Attribute Summary (collapse)

Class Method Summary (collapse)

Instance Method Summary (collapse)

Constructor Details

- (Attachment) initialize(name, instance, options = {})

Creates an Attachment object. name is the name of the attachment, instance is the model 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 filename_cleaner - An object that responds to #call(filename) that will strip unacceptable charcters from filename 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 escape_url - Perform URI escaping to URLs. Defaults to true



69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
# File 'lib/paperclip/attachment.rb', line 69

def initialize(name, instance, options = {})
  @name              = name
  @instance          = instance

  options = self.class.default_options.deep_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

Instance Attribute Details

- (Object) convert_options (readonly)

Returns the value of attribute convert_options



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def convert_options
  @convert_options
end

- (Object) default_style (readonly)

Returns the value of attribute default_style



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def default_style
  @default_style
end

- (Object) instance (readonly)

Returns the value of attribute instance



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def instance
  @instance
end

- (Object) interpolator (readonly)

Returns the value of attribute interpolator



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def interpolator
  @interpolator
end

- (Object) name (readonly)

Returns the value of attribute name



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def name
  @name
end

- (Object) options (readonly)

Returns the value of attribute options



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def options
  @options
end

- (Object) post_processing

Returns the value of attribute post_processing



40
41
42
# File 'lib/paperclip/attachment.rb', line 40

def post_processing
  @post_processing
end

- (Object) queued_for_write (readonly)

Returns the value of attribute queued_for_write



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def queued_for_write
  @queued_for_write
end

- (Object) source_file_options (readonly)

Returns the value of attribute source_file_options



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def source_file_options
  @source_file_options
end

- (Object) whiny (readonly)

Returns the value of attribute whiny



38
39
40
# File 'lib/paperclip/attachment.rb', line 38

def whiny
  @whiny
end

Class Method Details

+ (Object) default_options



11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
# File 'lib/paperclip/attachment.rb', line 11

def self.default_options
  @default_options ||= {
    :convert_options       => {},
    :default_style         => :original,
    :default_url           => "/:attachment/:style/missing.png",
    :escape_url            => true,
    :restricted_characters => /[&$+,\/:;=?@<>\[\]\{\}\|\\\^~%# ]/,
    :filename_cleaner      => nil,
    :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],
    :check_validity_before_processing => true
  }
end

Instance Method Details

- (Object) as_json(options = nil)



188
189
190
# File 'lib/paperclip/attachment.rb', line 188

def as_json(options = nil)
  to_s((options && options[:style]) || default_style)
end

- (Object) assign(uploaded_file)

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


95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
# File 'lib/paperclip/attachment.rb', line 95

def assign uploaded_file
  ensure_required_accessors!
  ensure_required_validations!
  file = Paperclip.io_adapters.for(uploaded_file)

  return nil if not file.assignment?
  self.clear(*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(*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)
  updater = :#{name}_file_name_will_change!"
  instance.send updater if instance.respond_to? updater
end

- (Boolean) blank?

Returns:

  • (Boolean)


355
356
357
# File 'lib/paperclip/attachment.rb', line 355

def blank?
  not present?
end

- (Object) clear(*styles_to_clear)

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.



247
248
249
250
251
252
253
254
255
# File 'lib/paperclip/attachment.rb', line 247

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

- (Object) content_type

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



290
291
292
# File 'lib/paperclip/attachment.rb', line 290

def content_type
  instance_read(:content_type)
end

- (Object) created_at

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



296
297
298
299
300
301
# File 'lib/paperclip/attachment.rb', line 296

def created_at
  if able_to_store_created_at?
    time = instance_read(:created_at)
    time && time.to_f.to_i
  end
end

- (Object) destroy

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.



260
261
262
263
# File 'lib/paperclip/attachment.rb', line 260

def destroy
  clear
  save
end

- (Boolean) dirty?

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

Returns:

  • (Boolean)


231
232
233
# File 'lib/paperclip/attachment.rb', line 231

def dirty?
  @dirty
end

- (Object) errors

Returns an array containing the errors on this attachment.



226
227
228
# File 'lib/paperclip/attachment.rb', line 226

def errors
  @errors
end

- (Object) expiring_url(time = 3600, style_name = default_style)

Alias to url that allows using the expiring_url method provided by the cloud storage implementations, but keep using filesystem storage for development and testing.



158
159
160
# File 'lib/paperclip/attachment.rb', line 158

def expiring_url(time = 3600, style_name = default_style)
  url(style_name)
end

- (Boolean) file? Also known as: present?

Returns true if a file has been assigned.

Returns:

  • (Boolean)


349
350
351
# File 'lib/paperclip/attachment.rb', line 349

def file?
  !original_filename.blank?
end

- (Object) fingerprint

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



284
285
286
# File 'lib/paperclip/attachment.rb', line 284

def fingerprint
  instance_read(:fingerprint)
end

- (Object) hash_key(style_name = default_style)

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

Raises:

  • (ArgumentError)


318
319
320
321
322
323
# File 'lib/paperclip/attachment.rb', line 318

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

- (Object) instance_read(attr)

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



377
378
379
380
381
382
# File 'lib/paperclip/attachment.rb', line 377

def instance_read(attr)
  getter = :#{name}_#{attr}"
  if instance.respond_to?(getter)
    instance.send(getter)
  end
end

- (Boolean) instance_respond_to?(attr)

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

Returns:

  • (Boolean)


361
362
363
# File 'lib/paperclip/attachment.rb', line 361

def instance_respond_to?(attr)
  instance.respond_to?(:#{name}_#{attr}")
end

- (Object) instance_write(attr, value)

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).



368
369
370
371
372
373
# File 'lib/paperclip/attachment.rb', line 368

def instance_write(attr, value)
  setter = :#{name}_#{attr}="
  if instance.respond_to?(setter)
    instance.send(setter, value)
  end
end

- (Object) only_process



209
210
211
212
213
# File 'lib/paperclip/attachment.rb', line 209

def only_process
  only_process = @options[:only_process].dup
  only_process = only_process.call(self) if only_process.respond_to?(:call)
  only_process.map(&:to_sym)
end

- (Object) original_filename

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



272
273
274
# File 'lib/paperclip/attachment.rb', line 272

def original_filename
  instance_read(:file_name)
end

- (Object) path(style_name = default_style)

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.



166
167
168
169
# File 'lib/paperclip/attachment.rb', line 166

def path(style_name = default_style)
  path = original_filename.nil? ? nil : interpolate(path_option, style_name)
  path.respond_to?(:unescape) ? path.unescape : path
end

- (Object) processors



215
216
217
218
219
220
221
222
223
# File 'lib/paperclip/attachment.rb', line 215

def processors
  processing_option = @options[:processors]

  if processing_option.respond_to?(:call)
    processing_option.call(instance)
  else
    processing_option
  end
end

- (Object) reprocess!(*style_args)

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. NOTE: Calling reprocess WILL NOT delete existing files. This is due to inconsistencies in timing of S3 commands. It's possible that calling #reprocess! will lose data if the files are not kept.



332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
# File 'lib/paperclip/attachment.rb', line 332

def reprocess!(*style_args)
  saved_only_process, @options[:only_process] = @options[:only_process], style_args
  saved_preserve_files, @options[:preserve_files] = @options[:preserve_files], true
  begin
    assign(self)
    save
    instance.save
  rescue Errno::EACCES => e
    warn "#{e} - skipping file."
    false
  ensure
    @options[:only_process] = saved_only_process
    @options[:preserve_files] = saved_preserve_files
  end
end

- (Object) save

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.



237
238
239
240
241
242
# File 'lib/paperclip/attachment.rb', line 237

def save
  flush_deletes unless @options[:keep_old_files]
  flush_writes
  @dirty = false
  true
end

- (Object) size

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



278
279
280
# File 'lib/paperclip/attachment.rb', line 278

def size
  instance_read(:file_size) || (@queued_for_write[:original] && @queued_for_write[:original].size)
end

- (Boolean) staged?

:nodoc:

Returns:

  • (Boolean)


179
180
181
# File 'lib/paperclip/attachment.rb', line 179

def staged?
  ! @queued_for_write.empty?
end

- (Object) staged_path(style_name = default_style)

:nodoc:



172
173
174
175
176
# File 'lib/paperclip/attachment.rb', line 172

def staged_path(style_name = default_style)
  if staged?
    @queued_for_write[style_name].path
  end
end

- (Object) styles



196
197
198
199
200
201
202
203
204
205
206
207
# File 'lib/paperclip/attachment.rb', line 196

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

- (Object) time_zone

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



312
313
314
# File 'lib/paperclip/attachment.rb', line 312

def time_zone
  @options[:use_default_time_zone] ? Time.zone_default : Time.zone
end

- (Object) to_s(style_name = default_style)

Alias to url



184
185
186
# File 'lib/paperclip/attachment.rb', line 184

def to_s style_name = default_style
  url(style_name)
end

- (Object) updated_at

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



305
306
307
308
# File 'lib/paperclip/attachment.rb', line 305

def updated_at
  time = instance_read(:updated_at)
  time && time.to_f.to_i
end

- (Object) uploaded_file

Returns the uploaded file if present.



266
267
268
# File 'lib/paperclip/attachment.rb', line 266

def uploaded_file
  instance_read(:uploaded_file)
end

- (Object) url(style_name = default_style, options = {})

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)+



145
146
147
148
149
150
151
152
153
# File 'lib/paperclip/attachment.rb', line 145

def url(style_name = default_style, options = {})
  default_options = {:timestamp => @options[:use_timestamp], :escape => @options[:escape_url]}

  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