Module: Paperclip::Storage::Azure

Defined in:
lib/paperclip/storage/azure.rb,
lib/paperclip/storage/azure/environment.rb

Overview

Azure’s container file hosting service is a scalable, easy place to store files for distribution. You can find out more about it at azure.microsoft.com/en-us/services/storage/

To use Paperclip with Azure, include the azure gem in your Gemfile:

gem 'azure'

There are a few Azure-specific options for has_attached_file:

  • azure_credentials: Takes a path, a File, a Hash or a Proc. The path (or File) must point to a YAML file containing the access_key and storage_account that azure gives you. You can ‘environment-space’ this just like you do to your database.yml file, so different environments can use different accounts:

    development:
  storage_account_name: foo
  access_key: 123...
test:
  storage_account_name: foo
  access_key: abc...
production:
  storage_account_name: foo
  access_key: 456...

    This is not required, however, and the file may simply look like this:

    storage_account_name: foo
access_key: 456...

    In which case, those access keys will be used in all environments. You can also put your container name in this file, instead of adding it to the code directly. This is useful when you want the same account but a different container for development versus production. When using a Proc it provides a single parameter which is the attachment itself. A method #instance is available on the attachment which will take you back to your code. eg.

    class User
  has_attached_file :download,
                    :storage => :azure,
                    :azure_credentials => Proc.new{|a| a.instance.azure_credentials }

  def azure_credentials
    { :container => "xxx", :storage_account_name => "xxx", :access_key => "xxx" }
  end
end

  • container: This is the name of the Azure container that will store your files. Remember that the container must be unique across the storage account. If the container does not exist Paperclip will attempt to create it. The container name will not be interpolated. You can define the container as a Proc if you want to determine it’s name at runtime. Paperclip will call that Proc with attachment as the only argument.

  • path: This is the key under the container in which the file will be stored. The URL will be constructed from the container and the path. This is what you will want to interpolate. Keys should be unique, like filenames, and despite the fact that Azure (strictly speaking) does not support directories, you can still use a / to separate parts of your file name.

  • region: Depending on the region, different base urls are used. Supported values :global, :de

Defined Under Namespace

Classes: Environment

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(base) ⇒ Object 



57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
 
# File 'lib/paperclip/storage/azure.rb', line 57

def self.extended base
  begin
    require 'azure'
  rescue LoadError => e
    e.message << " (You may need to install the azure SDK gem)"
    raise e
  end unless defined?(::Azure::Core)

  base.instance_eval do
    @azure_options     = @options[:azure_options]     || {}
  end

  Paperclip.interpolates(:azure_path_url) do |attachment, style|
    attachment.azure_uri(style)
  end unless Paperclip::Interpolations.respond_to? :azure_path_url
end

Instance Method Details

#auto_connect_duration ⇒ Object 



92
93
94
95
 
# File 'lib/paperclip/storage/azure.rb', line 92

def auto_connect_duration
  @auto_connect_duration ||= @options[:auto_connect_duration] || azure_credentials[:auto_connect_duration] || 10
  @auto_connect_duration
end

#azure_account_name ⇒ Object 



101
102
103
104
105
106
 
# File 'lib/paperclip/storage/azure.rb', line 101

def 
   = @options[:azure_storage_account_name] || azure_credentials[:storage_account_name]
   = .call(self) if .is_a?(Proc)

  
end

#azure_base_url ⇒ Object 



172
173
174
 
# File 'lib/paperclip/storage/azure.rb', line 172

def azure_base_url
  Environment.url_for , @azure_credentials[:region]
end

#azure_container ⇒ Object 



176
177
178
 
# File 'lib/paperclip/storage/azure.rb', line 176

def azure_container
  @azure_container ||= azure_interface.get_container_properties container_name
end

#azure_credentials ⇒ Object 



97
98
99
 
# File 'lib/paperclip/storage/azure.rb', line 97

def azure_credentials
  @azure_credentials ||= parse_credentials(@options[:azure_credentials])
end

#azure_interface ⇒ Object 



114
115
116
117
118
119
120
121
122
123
124
 
# File 'lib/paperclip/storage/azure.rb', line 114

def azure_interface
  @azure_interface ||= begin
    config = {}

    [:storage_account_name, :access_key, :container].each do |opt|
      config[opt] = azure_credentials[opt] if azure_credentials[opt]
    end

    obtain_azure_instance_for(config.merge(@azure_options))
  end
end

#azure_object(style_name = default_style) ⇒ Object 



180
181
182
 
# File 'lib/paperclip/storage/azure.rb', line 180

def azure_object(style_name = default_style)
  azure_interface.get_blob_properties container_name, path(style_name).sub(%r{\A/},'')
end

#azure_uri(style_name = default_style) ⇒ Object 



168
169
170
 
# File 'lib/paperclip/storage/azure.rb', line 168

def azure_uri(style_name = default_style)
  "#{azure_base_url}/#{container_name}/#{path(style_name).gsub(%r{\A/}, '')}"
end

#container_name ⇒ Object 



108
109
110
111
112
 
# File 'lib/paperclip/storage/azure.rb', line 108

def container_name
  @container ||= @options[:container] || azure_credentials[:container]
  @container = @container.call(self) if @container.respond_to?(:call)
  @container or raise ArgumentError, "missing required :container option"
end

#copy_to_local_file(style, local_dest_path) ⇒ Object 



268
269
270
271
272
273
274
275
276
277
278
279
280
281
 
# File 'lib/paperclip/storage/azure.rb', line 268

def copy_to_local_file(style, local_dest_path)
  log("copying #{path(style)} to local file #{local_dest_path}")

  blob, content = azure_interface.get_blob(container_name, path(style).sub(%r{\A/},''))

  ::File.open(local_dest_path, 'wb') do |local_file|
    local_file.write(content)
  end
rescue ::Azure::Core::Http::HTTPError => e
  raise unless e.status_code == 404

  warn("#{e} - cannot copy #{path(style)} to local file #{local_dest_path}")
  false
end

#create_container ⇒ Object 



203
204
205
 
# File 'lib/paperclip/storage/azure.rb', line 203

def create_container
  azure_interface.create_container container_name
end

#exists?(style = default_style) ⇒ Boolean

Returns:

  • (Boolean) 


191
192
193
194
195
196
197
198
199
200
201
 
# File 'lib/paperclip/storage/azure.rb', line 191

def exists?(style = default_style)
  if original_filename
    !azure_object(style).nil?
  else
    false
  end
rescue ::Azure::Core::Http::HTTPError => e
  raise unless e.status_code == 404

  false
end

#expiring_url(time = 3600, style_name = default_style) ⇒ Object 



74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/paperclip/storage/azure.rb', line 74

def expiring_url(time = 3600, style_name = default_style)
  if path(style_name)
    uri = azure_uri(style_name)
    signer = ::Azure::Core::Auth::SharedAccessSignature.new(uri, {
        resource:    'b',
        permissions: 'r',
        start:       5.minutes.ago.utc.iso8601,
        expiry:      time.since.utc.iso8601,
        access_key:  azure_credentials[:access_key]
      },
      
    )
    signer.sign
  else
    url(style_name)
  end
end

#flush_deletes ⇒ Object

:nodoc:



255
256
257
258
259
260
261
262
263
264
265
266
 
# File 'lib/paperclip/storage/azure.rb', line 255

def flush_deletes #:nodoc:
  @queued_for_delete.each do |path|
    begin
      log("deleting #{path}")

      azure_interface.delete_blob container_name, path
    rescue ::Azure::Core::Http::HTTPError => e
      raise unless e.status_code == 404
    end
  end
  @queued_for_delete = []
end

#flush_writes ⇒ Object

:nodoc:



207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
 
# File 'lib/paperclip/storage/azure.rb', line 207

def flush_writes #:nodoc:
  @queued_for_write.each do |style, file|
    retries = 0
    begin
      log("saving #{path(style)}")

      write_options = {
        content_type: file.content_type,
      }

      if azure_container
        save_blob container_name, path(style).sub(%r{\A/},''), file, write_options
      end
    rescue ::Azure::Core::Http::HTTPError => e
      if e.status_code == 404
        create_container
        retry
      else
        raise
      end
    ensure
      file.rewind
    end
  end

  after_flush_writes # allows attachment to clean up temp files

  @queued_for_write = {}
end

#obtain_azure_instance_for(options) ⇒ Object 



126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
 
# File 'lib/paperclip/storage/azure.rb', line 126

def obtain_azure_instance_for(options)
  instances = (Thread.current[:paperclip_azure_instances] ||= {})

  unless instances[options]
    signer = ::Azure::Core::Auth::SharedKey.new options[:storage_account_name], options[:access_key]
    service = ::Azure::BlobService.new(signer, options[:storage_account_name])

    require 'azure/core/http/retry_policy' # For Some Reason, All Other Loading Locations Fail
    service.filters << ::Azure::Core::Http::RetryPolicy.new do |response, retry_data|
      status_code = case
                    when !response.nil?
                      response.status_code
                    when !retry_data[:error].nil?
                      retry_data[:error].status_code
                    else
                      500
                    end
      status_code = 500 if status_code == 0
      retry_data[:count] ||= 0

      if  (!response.nil? && response.success? && retry_data[:error].nil?) ||
          (status_code >= 300 && status_code < 500 && status_code != 408) ||
          status_code == 501 ||
          status_code == 505 ||
          (!retry_data[:error].nil? && retry_data[:error].description == 'Blob type of the blob reference doesn\'t match blob type of the blob.') ||
          retry_data[:count] >= 5
        retry_data[:count] = 0
      else
        retry_data[:count] += 1

        sleep (retry_data[:count] - 1) * 5
      end

      retry_data[:count] > 0
    end

    instances[options] = service
  end

  instances[options]
end

#parse_credentials(creds) ⇒ Object 



184
185
186
187
188
189
 
# File 'lib/paperclip/storage/azure.rb', line 184

def parse_credentials(creds)
  creds = creds.respond_to?('call') ? creds.call(self) : creds
  creds = find_credentials(creds).stringify_keys
  env = Object.const_defined?(:Rails) ? Rails.env : nil
  (creds[env] || creds).symbolize_keys
end

#save_blob(container_name, storage_path, file, write_options) ⇒ Object 



237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
 
# File 'lib/paperclip/storage/azure.rb', line 237

def save_blob(container_name, storage_path, file, write_options)

  if file.size < 64.megabytes
    azure_interface.create_block_blob container_name, storage_path, file.read, write_options
  else
    blocks = []; count = 0
    while data = file.read(4.megabytes)
      block_id = "block_#{(count += 1).to_s.rjust(5, '0')}"

      azure_interface.create_blob_block container_name, storage_path, block_id, data

      blocks << [block_id]
    end

    azure_interface.commit_blob_blocks container_name, storage_path, blocks
  end
end