diff options
Diffstat (limited to 'actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/conditionalget.rb')
-rw-r--r-- | actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/conditionalget.rb | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/conditionalget.rb b/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/conditionalget.rb new file mode 100644 index 0000000000..046ebdb00a --- /dev/null +++ b/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/conditionalget.rb @@ -0,0 +1,47 @@ +require 'rack/utils' + +module Rack + + # Middleware that enables conditional GET using If-None-Match and + # If-Modified-Since. The application should set either or both of the + # Last-Modified or Etag response headers according to RFC 2616. When + # either of the conditions is met, the response body is set to be zero + # length and the response status is set to 304 Not Modified. + # + # Applications that defer response body generation until the body's each + # message is received will avoid response body generation completely when + # a conditional GET matches. + # + # Adapted from Michael Klishin's Merb implementation: + # http://github.com/wycats/merb-core/tree/master/lib/merb-core/rack/middleware/conditional_get.rb + class ConditionalGet + def initialize(app) + @app = app + end + + def call(env) + return @app.call(env) unless %w[GET HEAD].include?(env['REQUEST_METHOD']) + + status, headers, body = @app.call(env) + headers = Utils::HeaderHash.new(headers) + if etag_matches?(env, headers) || modified_since?(env, headers) + status = 304 + headers.delete('Content-Type') + headers.delete('Content-Length') + body = [] + end + [status, headers, body] + end + + private + def etag_matches?(env, headers) + etag = headers['Etag'] and etag == env['HTTP_IF_NONE_MATCH'] + end + + def modified_since?(env, headers) + last_modified = headers['Last-Modified'] and + last_modified == env['HTTP_IF_MODIFIED_SINCE'] + end + end + +end |