Module: Paperclip::Storage::Fog

Defined in:
lib/paperclip/storage/fog.rb

Overview

fog is a modern and versatile cloud computing library for Ruby. Among others, it supports Amazon S3 to store your files. In contrast to the outdated AWS-S3 gem it is actively maintained and supports multiple locations. Amazon’s S3 file hosting service is a scalable, easy place to store files for distribution. You can find out more about it at aws.amazon.com/s3 There are a few fog-specific options for has_attached_file, which will be explained using S3 as an example:

  • fog_credentials: Takes a Hash with your credentials. For S3, you can use the following format:

    aws_access_key_id: '<your aws_access_key_id>'
    aws_secret_access_key: '<your aws_secret_access_key>'
    provider: 'AWS'
    region: 'eu-west-1'
    
  • fog_directory: This is the name of the S3 bucket that will store your files. Remember that the bucket must be unique across all of Amazon S3. If the bucket does not exist, Paperclip will attempt to create it.

  • path: This is the key under the bucket in which the file will be stored. The URL will be constructed from the bucket and the path. This is what you will want to interpolate. Keys should be unique, like filenames, and despite the fact that S3 (strictly speaking) does not support directories, you can still use a / to separate parts of your file name.

  • fog_public: (optional, defaults to true) Should the uploaded files be public or not? (true/false)

  • fog_host: (optional) The fully-qualified domain name (FQDN) that is the alias to the S3 domain of your bucket, e.g. ‘images.example.com’. This can also be used in conjunction with Cloudfront (aws.amazon.com/cloudfront)

Constant Summary collapse

AWS_BUCKET_SUBDOMAIN_RESTRICTON_REGEX =
/^(?:[a-z]|\d(?!\d{0,2}(?:\.\d{1,3}){3}$))(?:[a-z0-9]|\.(?![\.\-])|\-(?![\.])){1,61}[a-z0-9]$/

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(base) ⇒ Object



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# File 'lib/paperclip/storage/fog.rb', line 35

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

  base.instance_eval do
    unless @options[:url].to_s.match(/^:fog.*url$/)
      @options[:path]  = @options[:path].gsub(/:url/, @options[:url])
      @options[:url]   = ':fog_public_url'
    end
    Paperclip.interpolates(:fog_public_url) do |attachment, style|
      attachment.public_url(style)
    end unless Paperclip::Interpolations.respond_to? :fog_public_url
  end
end

Instance Method Details

#copy_to_local_file(style, local_dest_path) ⇒ Object



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# File 'lib/paperclip/storage/fog.rb', line 138

def copy_to_local_file(style, local_dest_path)
  log("copying #{path(style)} to local file #{local_dest_path}")
  local_file = ::File.open(local_dest_path, 'wb')
  file = directory.files.get(path(style))
  local_file.write(file.body)
  local_file.close
rescue Fog::Errors::Error => e
  warn("#{e} - cannot copy #{path(style)} to local file #{local_dest_path}")
  false
end

#exists?(style = default_style) ⇒ Boolean

Returns:

  • (Boolean)


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

def exists?(style = default_style)
  if original_filename
    !!directory.files.head(path(style))
  else
    false
  end
end

#flush_deletesObject



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# File 'lib/paperclip/storage/fog.rb', line 101

def flush_deletes
  for path in @queued_for_delete do
    log("deleting #{path}")
    directory.files.new(:key => path).destroy
  end
  @queued_for_delete = []
end

#flush_writesObject



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# File 'lib/paperclip/storage/fog.rb', line 77

def flush_writes
  for style, file in @queued_for_write do
    log("saving #{path(style)}")
    retried = false
    begin
      directory.files.create(fog_file.merge(
        :body         => file,
        :key          => path(style),
        :public       => fog_public,
        :content_type => file.content_type
      ))
    rescue Excon::Errors::NotFound
      raise if retried
      retried = true
      directory.save
      retry
    end
  end

  after_flush_writes # allows attachment to clean up temp files

  @queued_for_write = {}
end

#fog_credentialsObject



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# File 'lib/paperclip/storage/fog.rb', line 64

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

#fog_fileObject



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# File 'lib/paperclip/storage/fog.rb', line 68

def fog_file
  @fog_file ||= @options[:fog_file] || {}
end

#fog_publicObject



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# File 'lib/paperclip/storage/fog.rb', line 72

def fog_public
  return @fog_public if defined?(@fog_public)
  @fog_public = defined?(@options[:fog_public]) ? @options[:fog_public] : true
end

#parse_credentials(creds) ⇒ Object



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# File 'lib/paperclip/storage/fog.rb', line 132

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

#public_url(style = default_style) ⇒ Object



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

def public_url(style = default_style)
  if @options[:fog_host]
    host = if @options[:fog_host].respond_to?(:call)
      @options[:fog_host].call(self)
    else
      (@options[:fog_host] =~ /%d/) ? @options[:fog_host] % (path(style).hash % 4) : @options[:fog_host]
    end

    "#{host}/#{path(style)}"
  else
    if fog_credentials[:provider] == 'AWS'
      if @options[:fog_directory].to_s =~ Fog::AWS_BUCKET_SUBDOMAIN_RESTRICTON_REGEX
        "https://#{@options[:fog_directory]}.s3.amazonaws.com/#{path(style)}"
      else
        # directory is not a valid subdomain, so use path style for access
        "https://s3.amazonaws.com/#{@options[:fog_directory]}/#{path(style)}"
      end
    else
      directory.files.new(:key => path(style)).public_url
    end
  end
end