require 'digest/md5' module ActionController # :nodoc: # Represents an HTTP response generated by a controller action. One can use an # ActionController::AbstractResponse object to retrieve the current state of the # response, or customize the response. An AbstractResponse object can either # represent a "real" HTTP response (i.e. one that is meant to be sent back to the # web browser) or a test response (i.e. one that is generated from integration # tests). See CgiResponse and TestResponse, respectively. # # AbstractResponse is mostly a Ruby on Rails framework implement detail, and should # never be used directly in controllers. Controllers should use the methods defined # in ActionController::Base instead. For example, if you want to set the HTTP # response's content MIME type, then use ActionControllerBase#headers instead of # AbstractResponse#headers. # # Nevertheless, integration tests may want to inspect controller responses in more # detail, and that's when AbstractResponse can be useful for application developers. # Integration test methods such as ActionController::Integration::Session#get and # ActionController::Integration::Session#post return objects of type TestResponse # (which are of course also of type AbstractResponse). # # For example, the following demo integration "test" prints the body of the # controller response to the console: # # class DemoControllerTest < ActionController::IntegrationTest # def test_print_root_path_to_console # get('/') # puts @response.body # end # end class AbstractResponse DEFAULT_HEADERS = { "Cache-Control" => "no-cache" } attr_accessor :request # The body content (e.g. HTML) of the response, as a String. attr_accessor :body # The headers of the response, as a Hash. It maps header names to header values. attr_accessor :headers attr_accessor :session, :cookies, :assigns, :template, :redirected_to, :redirected_to_method_params, :layout def initialize @body, @headers, @session, @assigns = "", DEFAULT_HEADERS.merge("cookie" => []), [], [] end # Sets the HTTP response's content MIME type. For example, in the controller # you could write this: # # response.content_type = "text/plain" # # If a character set has been defined for this response (see charset=) then # the character set information will also be included in the content type # information. def content_type=(mime_type) self.headers["Content-Type"] = charset ? "#{mime_type}; charset=#{charset}" : mime_type end # Returns the response's content MIME type, or nil if content type has been set. def content_type content_type = String(headers["Content-Type"] || headers["type"]).split(";")[0] content_type.blank? ? nil : content_type end def charset=(encoding) self.headers["Content-Type"] = "#{content_type || Mime::HTML}; charset=#{encoding}" end def charset charset = String(headers["Content-Type"] || headers["type"]).split(";")[1] charset.blank? ? nil : charset.strip.split("=")[1] end def redirect(to_url, response_status) self.headers["Status"] = response_status self.headers["Location"] = to_url self.body = "You are being redirected." end def prepare! handle_conditional_get! convert_content_type! set_content_length! end # Sets the Last-Modified response header. Returns whether it's older than # the If-Modified-Since request header. def last_modified!(utc_time) headers['Last-Modified'] ||= utc_time.httpdate if request && since = request.headers['HTTP_IF_MODIFIED_SINCE'] utc_time <= Time.rfc2822(since) end end # Sets the ETag response header. Returns whether it matches the # If-None-Match request header. def etag!(tag) headers['ETag'] ||= %("#{Digest::MD5.hexdigest(ActiveSupport::Cache.expand_cache_key(tag))}") if request && request.headers['HTTP_IF_NONE_MATCH'] == headers['ETag'] true end end private def handle_conditional_get! if nonempty_ok_response? set_conditional_cache_control! if etag!(body) headers['Status'] = '304 Not Modified' self.body = '' end end end def nonempty_ok_response? status = headers['Status'] ok = !status || status[0..2] == '200' ok && body.is_a?(String) && !body.empty? end def set_conditional_cache_control! if headers['Cache-Control'] == DEFAULT_HEADERS['Cache-Control'] headers['Cache-Control'] = 'private, max-age=0, must-revalidate' end end def convert_content_type! if content_type = headers.delete("Content-Type") self.headers["type"] = content_type end if content_type = headers.delete("Content-type") self.headers["type"] = content_type end if content_type = headers.delete("content-type") self.headers["type"] = content_type end end # Don't set the Content-Length for block-based bodies as that would mean reading it all into memory. Not nice # for, say, a 2GB streaming file. def set_content_length! self.headers["Content-Length"] = body.size unless body.respond_to?(:call) end end end