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/

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 storage_access_key and storage_account_name 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
  storage_access_key: 123...
test:
  storage_account_name: foo
  storage_access_key: abc...
production:
  storage_account_name: foo
  storage_access_key: 456...

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

    storage_account_name: foo
storage_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", :storage_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 



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# File 'lib/paperclip/storage/azure.rb', line 56

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]     || {}

    unless @options[:url].to_s.match(/\A:azure.*url\z/) || @options[:url] == ":asset_host".freeze
      @options[:path] = path_option.gsub(/:url/, @options[:url]).sub(/\A:rails_root\/public\/system/, "".freeze)
      @options[:url]  = ":azure_path_url".freeze
    end
    @options[:url] = @options[:url].inspect if @options[:url].is_a?(Symbol)

    @http_proxy = @options[:http_proxy] || nil
  end

  Paperclip.interpolates(:azure_path_url) do |attachment, style|
    attachment.azure_uri(style)
  end unless Paperclip::Interpolations.respond_to? :azure_path_url
  Paperclip.interpolates(:asset_host) do |attachment, style|
    "#{attachment.path(style).sub(%r{\A/}, "".freeze)}"
  end unless Paperclip::Interpolations.respond_to? :asset_host
end

Instance Method Details

#auto_connect_duration ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 100

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 



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# File 'lib/paperclip/storage/azure.rb', line 109

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

  
end

#azure_base_url ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 158

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

#azure_container ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 162

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

#azure_credentials ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 105

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

#azure_interface ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 122

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

    [:storage_account_name, :storage_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 



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# File 'lib/paperclip/storage/azure.rb', line 166

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

#azure_storage_client ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 134

def azure_storage_client
  config = {}

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

  @azure_storage_client ||= ::Azure::Storage::Client.create config
end

#azure_uri(style_name = default_style) ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 154

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

#container_name ⇒ Object 



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# File 'lib/paperclip/storage/azure.rb', line 116

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 



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# File 'lib/paperclip/storage/azure.rb', line 254

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 



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# File 'lib/paperclip/storage/azure.rb', line 189

def create_container
  azure_interface.create_container container_name
end

#exists?(style = default_style) ⇒ Boolean

Returns:

  • (Boolean) 


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

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 



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# File 'lib/paperclip/storage/azure.rb', line 84

def expiring_url(time = 3600, style_name = default_style)
  if path(style_name)
    uri = URI azure_uri(style_name)
    generator = ::Azure::Storage::Core::Auth::SharedAccessSignature.new ,
                                                                        azure_credentials[:storage_access_key]

    generator.signed_uri uri, false, service:      'b',
                                     resource:     'b',
                                     permissions:  'r',
                                     start:        (Time.now - (5 * 60)).utc.iso8601,
                                     expiry:       (Time.now + time).utc.iso8601
  else
    url(style_name)
  end
end

#flush_deletes ⇒ Object

:nodoc:



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# File 'lib/paperclip/storage/azure.rb', line 241

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:



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# File 'lib/paperclip/storage/azure.rb', line 193

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 



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# File 'lib/paperclip/storage/azure.rb', line 144

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

  service = ::Azure::Storage::Blob::BlobService.new(client: azure_storage_client)
  service.with_filter ::Azure::Storage::Core::Filter::ExponentialRetryPolicyFilter.new

  instances[options] = service
end

#parse_credentials(creds) ⇒ Object 



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

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 



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# File 'lib/paperclip/storage/azure.rb', line 223

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