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Diffstat (limited to 'actionpack/lib/action_controller/metal/streaming.rb')
-rw-r--r-- | actionpack/lib/action_controller/metal/streaming.rb | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/metal/streaming.rb b/actionpack/lib/action_controller/metal/streaming.rb new file mode 100644 index 0000000000..57318e8747 --- /dev/null +++ b/actionpack/lib/action_controller/metal/streaming.rb @@ -0,0 +1,187 @@ +require 'active_support/core_ext/string/bytesize' + +module ActionController #:nodoc: + # Methods for sending arbitrary data and for streaming files to the browser, + # instead of rendering. + module Streaming + extend ActiveSupport::Concern + + include ActionController::RenderingController + + DEFAULT_SEND_FILE_OPTIONS = { + :type => 'application/octet-stream'.freeze, + :disposition => 'attachment'.freeze, + :stream => true, + :buffer_size => 4096, + :x_sendfile => false + }.freeze + + X_SENDFILE_HEADER = 'X-Sendfile'.freeze + + protected + # Sends the file, by default streaming it 4096 bytes at a time. This way the + # whole file doesn't need to be read into memory at once. This makes it + # feasible to send even large files. You can optionally turn off streaming + # and send the whole file at once. + # + # Be careful to sanitize the path parameter if it is coming from a web + # page. <tt>send_file(params[:path])</tt> allows a malicious user to + # download any file on your server. + # + # Options: + # * <tt>:filename</tt> - suggests a filename for the browser to use. + # Defaults to <tt>File.basename(path)</tt>. + # * <tt>:type</tt> - 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 <tt>Mime::Type.register</tt>, for example :json + # * <tt>:length</tt> - used to manually override the length (in bytes) of the content that + # is going to be sent to the client. Defaults to <tt>File.size(path)</tt>. + # * <tt>:disposition</tt> - specifies whether the file will be shown inline or downloaded. + # Valid values are 'inline' and 'attachment' (default). + # * <tt>:stream</tt> - whether to send the file to the user agent as it is read (+true+) + # or to read the entire file before sending (+false+). Defaults to +true+. + # * <tt>:buffer_size</tt> - specifies size (in bytes) of the buffer used to stream the file. + # Defaults to 4096. + # * <tt>:status</tt> - specifies the status code to send with the response. Defaults to '200 OK'. + # * <tt>:url_based_filename</tt> - set to +true+ if you want the browser guess the filename from + # the URL, which is necessary for i18n filenames on certain browsers + # (setting <tt>:filename</tt> overrides this option). + # * <tt>:x_sendfile</tt> - uses X-Sendfile to send the file when set to +true+. This is currently + # only available with Lighttpd/Apache2 and specific modules installed and activated. Since this + # uses the web server to send the file, this may lower memory consumption on your server and + # it will not block your application for further requests. + # See http://blog.lighttpd.net/articles/2006/07/02/x-sendfile and + # http://tn123.ath.cx/mod_xsendfile/ for details. Defaults to +false+. + # + # 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[:length] ||= File.size(path) + options[:filename] ||= File.basename(path) unless options[:url_based_filename] + send_file_headers! options + + @performed_render = false + + if options[:x_sendfile] + logger.info "Sending #{X_SENDFILE_HEADER} header #{path}" if logger + head options[:status], X_SENDFILE_HEADER => path + else + if options[:stream] + # TODO : Make render :text => proc {} work with the new base + render :status => options[:status], :text => Proc.new { |response, output| + logger.info "Streaming file #{path}" unless logger.nil? + len = options[:buffer_size] || 4096 + File.open(path, 'rb') do |file| + while buf = file.read(len) + output.write(buf) + end + end + } + else + logger.info "Sending file #{path}" unless logger.nil? + File.open(path, 'rb') { |file| render :status => options[:status], :text => file.read } + end + end + end + + # Sends the given binary data to the browser. This method is similar to + # <tt>render :text => data</tt>, 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: + # * <tt>:filename</tt> - suggests a filename for the browser to use. + # * <tt>:type</tt> - 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 <tt>Mime::Type.register</tt>, for example :json + # * <tt>:disposition</tt> - specifies whether the file will be shown inline or downloaded. + # Valid values are 'inline' and 'attachment' (default). + # * <tt>:status</tt> - specifies the status code to send with the response. Defaults to '200 OK'. + # + # 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. + # + # <b>Tip:</b> if you want to stream large amounts of on-the-fly generated + # data to the browser, then use <tt>render :text => proc { ... }</tt> + # instead. See ActionController::Base#render for more information. + def send_data(data, options = {}) #:doc: + logger.info "Sending data #{options[:filename]}" if logger + send_file_headers! options.merge(:length => data.bytesize) + @performed_render = false + render :status => options[:status], :text => data + end + + private + def send_file_headers!(options) + options.update(DEFAULT_SEND_FILE_OPTIONS.merge(options)) + [:length, :type, :disposition].each do |arg| + raise ArgumentError, ":#{arg} option required" if options[arg].nil? + end + + disposition = options[:disposition].dup || 'attachment' + + disposition <<= %(; filename="#{options[:filename]}") if options[:filename] + + content_type = options[:type] + + if content_type.is_a?(Symbol) + raise ArgumentError, "Unknown MIME type #{options[:type]}" unless Mime::EXTENSION_LOOKUP.key?(content_type.to_s) + self.content_type = Mime::Type.lookup_by_extension(content_type.to_s) + else + self.content_type = content_type + end + + headers.merge!( + 'Content-Length' => options[:length].to_s, + 'Content-Disposition' => disposition, + 'Content-Transfer-Encoding' => 'binary' + ) + + # 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 |