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 = "<html><body>You are being <a href=\"#{to_url}\">redirected</a>.</body></html>"
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
