require 'action_controller/metal/exceptions' module ActionController #:nodoc: # Methods for sending arbitrary data and for streaming files to the browser, # instead of rendering. module DataStreaming extend ActiveSupport::Concern include ActionController::Rendering DEFAULT_SEND_FILE_OPTIONS = { :type => 'application/octet-stream'.freeze, :disposition => 'attachment'.freeze, }.freeze protected # Sends the file. This uses a server-appropriate method (such as X-Sendfile) # via the Rack::Sendfile middleware. The header to use is set via # config.action_dispatch.x_sendfile_header. # Your server can also configure this for you by setting the X-Sendfile-Type header. # # Be careful to sanitize the path parameter if it is coming from a web # page. send_file(params[:path]) allows a malicious user to # download any file on your server. # # Options: # * :filename - suggests a filename for the browser to use. # Defaults to File.basename(path). # * :type - specifies an HTTP content type. # You can specify either a string or a symbol for a registered type register with # Mime::Type.register, for example :json # If omitted, type will be guessed from the file extension specified in :filename. # If no content type is registered for the extension, default type 'application/octet-stream' will be used. # * :disposition - specifies whether the file will be shown inline or downloaded. # Valid values are 'inline' and 'attachment' (default). # * :status - specifies the status code to send with the response. Defaults to 200. # * :url_based_filename - set to +true+ if you want the browser guess the filename from # the URL, which is necessary for i18n filenames on certain browsers # (setting :filename overrides this option). # # The default Content-Type and Content-Disposition headers are # set to download arbitrary binary files in as many browsers as # possible. IE versions 4, 5, 5.5, and 6 are all known to have # a variety of quirks (especially when downloading over SSL). # # Simple download: # # send_file '/path/to.zip' # # Show a JPEG in the browser: # # send_file '/path/to.jpeg', :type => 'image/jpeg', :disposition => 'inline' # # Show a 404 page in the browser: # # send_file '/path/to/404.html', :type => 'text/html; charset=utf-8', :status => 404 # # Read about the other Content-* HTTP headers if you'd like to # provide the user with more information (such as Content-Description) in # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11. # # Also be aware that the document may be cached by proxies and browsers. # The Pragma and Cache-Control headers declare how the file may be cached # by intermediaries. They default to require clients to validate with # the server before releasing cached responses. See # http://www.mnot.net/cache_docs/ for an overview of web caching and # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9 # for the Cache-Control header spec. def send_file(path, options = {}) #:doc: raise MissingFile, "Cannot read file #{path}" unless File.file?(path) and File.readable?(path) options[:filename] ||= File.basename(path) unless options[:url_based_filename] send_file_headers! options self.status = options[:status] || 200 self.content_type = options[:content_type] if options.key?(:content_type) self.response_body = FileBody.new(path) end # Avoid having to pass an open file handle as the response body. # Rack::Sendfile will usually intercepts the response and just uses # the path directly, so no reason to open the file. class FileBody #:nodoc: attr_reader :to_path def initialize(path) @to_path = path end # Stream the file's contents if Rack::Sendfile isn't present. def each File.open(to_path, 'rb') do |file| while chunk = file.read(16384) yield chunk end end end end # Sends the given binary data to the browser. This method is similar to # render :text => data, but also allows you to specify whether # the browser should display the response as a file attachment (i.e. in a # download dialog) or as inline data. You may also set the content type, # the apparent file name, and other things. # # Options: # * :filename - suggests a filename for the browser to use. # * :type - specifies an HTTP content type. Defaults to 'application/octet-stream'. You can specify # either a string or a symbol for a registered type register with Mime::Type.register, for example :json # If omitted, type will be guessed from the file extension specified in :filename. # If no content type is registered for the extension, default type 'application/octet-stream' will be used. # * :disposition - specifies whether the file will be shown inline or downloaded. # Valid values are 'inline' and 'attachment' (default). # * :status - specifies the status code to send with the response. Defaults to 200. # # Generic data download: # # send_data buffer # # Download a dynamically-generated tarball: # # send_data generate_tgz('dir'), :filename => 'dir.tgz' # # Display an image Active Record in the browser: # # send_data image.data, :type => image.content_type, :disposition => 'inline' # # See +send_file+ for more information on HTTP Content-* headers and caching. def send_data(data, options = {}) #:doc: send_file_headers! options.dup render options.slice(:status, :content_type).merge(:text => data) end private def send_file_headers!(options) type_provided = options.has_key?(:type) options.update(DEFAULT_SEND_FILE_OPTIONS.merge(options)) [:type, :disposition].each do |arg| raise ArgumentError, ":#{arg} option required" if options[arg].nil? end disposition = options[:disposition] disposition += %(; filename="#{options[:filename]}") if options[:filename] content_type = options[:type] if content_type.is_a?(Symbol) extension = Mime[content_type] raise ArgumentError, "Unknown MIME type #{options[:type]}" unless extension self.content_type = extension else if !type_provided && options[:filename] # If type wasn't provided, try guessing from file extension. content_type = Mime::Type.lookup_by_extension(File.extname(options[:filename]).downcase.delete('.')) || content_type end self.content_type = content_type end headers.merge!( 'Content-Disposition' => disposition, 'Content-Transfer-Encoding' => 'binary' ) response.sending_file = true # Fix a problem with IE 6.0 on opening downloaded files: # If Cache-Control: no-cache is set (which Rails does by default), # IE removes the file it just downloaded from its cache immediately # after it displays the "open/save" dialog, which means that if you # hit "open" the file isn't there anymore when the application that # is called for handling the download is run, so let's workaround that response.cache_control[:public] ||= false end end end