Class: Paperclip::Attachment

Inherits:
Object
  • Object
show all
Includes:
IOStream
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

Methods included from IOStream

#stream_to, #to_tempfile

Constructor Details

#initialize(name, instance, options = {}) ⇒ Attachment

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 don't specify an argument to 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 to clearing the attachment. Defaults to false
+interpolator+ - the object used to interpolate filenames and URLs. Defaults to Paperclip::Interpolations



59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
 
# File 'lib/paperclip/attachment.rb', line 59

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

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

  @options               = Paperclip::Options.new(self, options)
  @post_processing       = true
  @queued_for_delete     = []
  @queued_for_write      = {}
  @errors                = {}
  @dirty                 = false
  @interpolator          = (options[:interpolator] || Paperclip::Interpolations)

  initialize_storage
end

Instance Attribute Details

#convert_options ⇒ Object (readonly)

Returns the value of attribute convert_options.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def convert_options
  @convert_options
end

#default_style ⇒ Object (readonly)

Returns the value of attribute default_style.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def default_style
  @default_style
end

#instance ⇒ Object (readonly)

Returns the value of attribute instance.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def instance
  @instance
end

#interpolator ⇒ Object (readonly)

Returns the value of attribute interpolator.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def interpolator
  @interpolator
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def name
  @name
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def options
  @options
end

#post_processing ⇒ Object

Returns the value of attribute post_processing.



33
34
35
 
# File 'lib/paperclip/attachment.rb', line 33

def post_processing
  @post_processing
end

#queued_for_write ⇒ Object (readonly)

Returns the value of attribute queued_for_write.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def queued_for_write
  @queued_for_write
end

#whiny ⇒ Object (readonly)

Returns the value of attribute whiny.



32
33
34
 
# File 'lib/paperclip/attachment.rb', line 32

def whiny
  @whiny
end

Class Method Details

.default_options ⇒ Object 



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

def self.default_options
  @default_options ||= {
    :url                   => "/system/:attachment/:id/:style/:filename",
    :path                  => ":rails_root/public:url",
    :styles                => {},
    :only_process          => [],
    :processors            => [:thumbnail],
    :convert_options       => {},
    :source_file_options   => {},
    :default_url           => "/:attachment/:style/missing.png",
    :default_style         => :original,
    :storage               => :filesystem,
    :use_timestamp         => true,
    :whiny                 => Paperclip.options[:whiny] || Paperclip.options[:whiny_thumbnails],
    :use_default_time_zone => true,
    :hash_digest           => "SHA1",
    :hash_data             => ":class/:attachment/:id/:style/:updated_at",
    :preserve_files        => false
  }
end

.interpolations ⇒ Object

Paths and URLs can have a number of variables interpolated into them to vary the storage location based on name, id, style, class, etc. This method is a deprecated access into supplying and retrieving these interpolations. Future access should use either Paperclip.interpolates or extend the Paperclip::Interpolations module directly.



273
274
275
276
277
278
 
# File 'lib/paperclip/attachment.rb', line 273

def self.interpolations
  warn('[DEPRECATION] Paperclip::Attachment.interpolations is deprecated ' +
       'and will be removed from future versions. ' +
       'Use Paperclip.interpolates instead')
  Paperclip::Interpolations
end

Instance Method Details

#assign(uploaded_file) ⇒ Object

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



90
91
92
93
94
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
122
123
124
125
126
127
128
129
 
# File 'lib/paperclip/attachment.rb', line 90

def assign uploaded_file
  ensure_required_accessors!

  if uploaded_file.is_a?(Paperclip::Attachment)
    uploaded_filename = uploaded_file.original_filename
    uploaded_file = uploaded_file.to_file(:original)
    close_uploaded_file = uploaded_file.respond_to?(:close)
  end

  return nil unless valid_assignment?(uploaded_file)

  uploaded_file.binmode if uploaded_file.respond_to? :binmode
  self.clear

  return nil if uploaded_file.nil?

  uploaded_filename          ||= uploaded_file.original_filename
  @queued_for_write[:original] = to_tempfile(uploaded_file)
  uploaded_content_type        = extract_content_type(@queued_for_write[:original])
  instance_write(:file_name,     uploaded_filename.strip)
  instance_write(:content_type,  uploaded_content_type)
  instance_write(:file_size,     @queued_for_write[:original].size.to_i)
  instance_write(:fingerprint,   generate_fingerprint(uploaded_file))
  instance_write(:updated_at,    Time.now)

  if valid_media_type?(format_content_type)
    instance_write(:file_name,    real_filename)
    instance_write(:content_type, format_content_type)
  end

  @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.to_i)
  instance_write(:fingerprint, generate_fingerprint(@queued_for_write[:original]))
ensure
  uploaded_file.close if close_uploaded_file
end

#clear ⇒ Object

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.



186
187
188
189
190
 
# File 'lib/paperclip/attachment.rb', line 186

def clear
  queue_existing_for_delete
  @queued_for_write  = {}
  @errors            = {}
end

#content_type ⇒ Object

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



222
223
224
 
# File 'lib/paperclip/attachment.rb', line 222

def content_type
  instance_read(:content_type)
end

#destroy ⇒ Object

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.



195
196
197
198
199
200
 
# File 'lib/paperclip/attachment.rb', line 195

def destroy
  unless @options.preserve_files
    clear
    save
  end
end

#dirty? ⇒ Boolean

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

Returns:

  • (Boolean) 


170
171
172
 
# File 'lib/paperclip/attachment.rb', line 170

def dirty?
  @dirty
end

#errors ⇒ Object

Returns an array containing the errors on this attachment.



165
166
167
 
# File 'lib/paperclip/attachment.rb', line 165

def errors
  @errors
end

#extract_content_type(source) ⇒ Object 



258
259
260
261
262
263
264
265
266
 
# File 'lib/paperclip/attachment.rb', line 258

def extract_content_type(source)
  if @options.use_file_command && source.respond_to?(:type_from_file_command)
    source.type_from_file_command.to_s.strip
  elsif source.respond_to?(:content_type)
    source.content_type.to_s.strip
  else
    nil
  end
end

#file? ⇒ Boolean Also known as: present?

Returns true if a file has been assigned.

Returns:

  • (Boolean) 


308
309
310
 
# File 'lib/paperclip/attachment.rb', line 308

def file?
  !original_filename.blank?
end

#fingerprint ⇒ Object

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



216
217
218
 
# File 'lib/paperclip/attachment.rb', line 216

def fingerprint
  instance_read(:fingerprint) || (@queued_for_write[:original] && generate_fingerprint(@queued_for_write[:original]))
end

#generate_fingerprint(source) ⇒ Object 



248
249
250
251
252
253
254
255
256
 
# File 'lib/paperclip/attachment.rb', line 248

def generate_fingerprint(source)
  if source.respond_to?(:path) && source.path && !source.path.blank?
    Digest::MD5.file(source.path).to_s
  else
    data = source.read
    source.rewind if source.respond_to?(:rewind)
    Digest::MD5.hexdigest(data)
  end
end

#hash(style_name = default_style) ⇒ Object

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

Raises:

  • (ArgumentError) 


241
242
243
244
245
246
 
# File 'lib/paperclip/attachment.rb', line 241

def hash(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) ⇒ Object

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



326
327
328
329
330
331
332
 
# File 'lib/paperclip/attachment.rb', line 326

def instance_read(attr)
  getter = :"#{name}_#{attr}"
  responds = instance.respond_to?(getter)
  cached = self.instance_variable_get("@_#{getter}")
  return cached if cached
  instance.send(getter) if responds || attr.to_s == "file_name"
end

#instance_write(attr, value) ⇒ Object

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).



317
318
319
320
321
322
 
# File 'lib/paperclip/attachment.rb', line 317

def instance_write(attr, value)
  setter = :"#{name}_#{attr}="
  responds = instance.respond_to?(setter)
  self.instance_variable_set("@_#{setter.to_s.chop}", value)
  instance.send(setter, value) if responds || attr.to_s == "file_name"
end

#original_filename ⇒ Object

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



204
205
206
 
# File 'lib/paperclip/attachment.rb', line 204

def original_filename
  instance_read(:file_name)
end

#path(style_name = default_style) ⇒ Object

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.



147
148
149
 
# File 'lib/paperclip/attachment.rb', line 147

def path(style_name = default_style)
  original_filename.nil? ? nil : interpolate(@options.path, style_name)
end

#reprocess!(*style_args) ⇒ Object

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.



284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
 
# File 'lib/paperclip/attachment.rb', line 284

def reprocess!(*style_args)
  new_original = Tempfile.new("paperclip-reprocess")
  new_original.binmode
  if old_original = to_file(:original)
    new_original.write( old_original.respond_to?(:get) ? old_original.get : old_original.read )
    new_original.rewind

    @queued_for_write = { :original => new_original }
    instance_write(:updated_at, Time.now)
    post_process(*style_args)

    old_original.close if old_original.respond_to?(:close)
    old_original.unlink if old_original.respond_to?(:unlink)

    save
  else
    true
  end
rescue Errno::EACCES => e
  warn "#{e} - skipping file"
  false
end

#save ⇒ Object

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.



176
177
178
179
180
181
 
# File 'lib/paperclip/attachment.rb', line 176

def save
  flush_deletes
  flush_writes
  @dirty = false
  true
end

#size ⇒ Object

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



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

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

#styles ⇒ Object 



160
161
162
 
# File 'lib/paperclip/attachment.rb', line 160

def styles
  @options.styles
end

#time_zone ⇒ Object

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



235
236
237
 
# File 'lib/paperclip/attachment.rb', line 235

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

#to_s(style_name = default_style) ⇒ Object

Alias to url



152
153
154
 
# File 'lib/paperclip/attachment.rb', line 152

def to_s style_name = default_style
  url(style_name)
end

#updated_at ⇒ Object

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



228
229
230
231
 
# File 'lib/paperclip/attachment.rb', line 228

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

#url(style_name = default_style, use_timestamp = @options.use_timestamp) ⇒ Object

Returns the public URL of the attachment, with a given style. Note that this does not necessarily need to point to a file that your web server can access and can point to an action in your app, if you need fine grained security. This is not recommended if you don’t need the security, however, for performance reasons. Set use_timestamp to false if you want to stop the attachment update time appended to the url



137
138
139
140
141
 
# File 'lib/paperclip/attachment.rb', line 137

def url(style_name = default_style, use_timestamp = @options.use_timestamp)
  default_url = @options.default_url.is_a?(Proc) ? @options.default_url.call(self) : @options.default_url
  url = original_filename.nil? ? interpolate(default_url, style_name) : interpolate(@options.url, style_name)
  URI.escape(use_timestamp && updated_at ? [url, updated_at].compact.join(url.include?("?") ? "&" : "?") : url)
end