Revert "Add common HTTP strings to Rack::Const"

This reverts commit 6ae0a1014c2bfc06ad4d91ea04da5c42be454079.

41 files changed, 319 insertions, 383 deletions

diff --git a/lib/rack.rb b/lib/rack.rb
index a19ac2db..371d0156 100644
--- a/lib/rack.rb
+++ b/lib/rack.rb
@@ -32,7 +32,6 @@ module Rack
   autoload :Chunked, "rack/chunked"
   autoload :CommonLogger, "rack/commonlogger"
   autoload :ConditionalGet, "rack/conditionalget"
-  autoload :Const, "rack/constants"
   autoload :ContentLength, "rack/content_length"
   autoload :ContentType, "rack/content_type"
   autoload :File, "rack/file"
diff --git a/lib/rack/adapter/camping.rb b/lib/rack/adapter/camping.rb
index 8eb32318..63bc787f 100644
--- a/lib/rack/adapter/camping.rb
+++ b/lib/rack/adapter/camping.rb
@@ -6,9 +6,9 @@ module Rack
       end
 
       def call(env)
-        env[Const::ENV_PATH_INFO] ||= ""
-        env[Const::ENV_SCRIPT_NAME] ||= ""
-        controller = @app.run(env[Const::RACK_INPUT], env)
+        env["PATH_INFO"] ||= ""
+        env["SCRIPT_NAME"] ||= ""
+        controller = @app.run(env['rack.input'], env)
         h = controller.headers
         h.each_pair do |k,v|
           if v.kind_of? URI
diff --git a/lib/rack/auth/abstract/handler.rb b/lib/rack/auth/abstract/handler.rb
index a08e5287..214df629 100644
--- a/lib/rack/auth/abstract/handler.rb
+++ b/lib/rack/auth/abstract/handler.rb
@@ -17,8 +17,8 @@ module Rack
 
       def unauthorized(www_authenticate = challenge)
         return [ 401,
-          { Const::CONTENT_TYPE => 'text/plain',
-            Const::CONTENT_LENGTH => '0',
+          { 'Content-Type' => 'text/plain',
+            'Content-Length' => '0',
             'WWW-Authenticate' => www_authenticate.to_s },
           []
         ]
@@ -26,8 +26,8 @@ module Rack
 
       def bad_request
         return [ 400,
-          { Const::CONTENT_TYPE => 'text/plain',
-            Const::CONTENT_LENGTH => '0' },
+          { 'Content-Type' => 'text/plain',
+            'Content-Length' => '0' },
           []
         ]
       end
diff --git a/lib/rack/auth/basic.rb b/lib/rack/auth/basic.rb
index a2fae961..95572246 100644
--- a/lib/rack/auth/basic.rb
+++ b/lib/rack/auth/basic.rb
@@ -20,7 +20,7 @@ module Rack
         return bad_request unless auth.basic?
 
         if valid?(auth)
-          env[Const::ENV_REMOTE_USER] = auth.username
+          env['REMOTE_USER'] = auth.username
 
           return @app.call(env)
         end
diff --git a/lib/rack/auth/digest/md5.rb b/lib/rack/auth/digest/md5.rb
index 33a9da06..e579dc96 100644
--- a/lib/rack/auth/digest/md5.rb
+++ b/lib/rack/auth/digest/md5.rb
@@ -45,7 +45,7 @@ module Rack
             if auth.nonce.stale?
               return unauthorized(challenge(:stale => true))
             else
-              env[Const::ENV_REMOTE_USER] = auth.username
+              env['REMOTE_USER'] = auth.username
 
               return @app.call(env)
             end
diff --git a/lib/rack/auth/digest/request.rb b/lib/rack/auth/digest/request.rb
index 1134b443..a8aa3bf9 100644
--- a/lib/rack/auth/digest/request.rb
+++ b/lib/rack/auth/digest/request.rb
@@ -8,7 +8,7 @@ module Rack
       class Request < Auth::AbstractRequest
 
         def method
-          @env['rack.methodoverride.original_method'] || @env[Const::ENV_REQUEST_METHOD]
+          @env['rack.methodoverride.original_method'] || @env['REQUEST_METHOD']
         end
 
         def digest?
@@ -16,7 +16,7 @@ module Rack
         end
 
         def correct_uri?
-          (@env[Const::ENV_SCRIPT_NAME].to_s + @env[Const::ENV_PATH_INFO].to_s) == uri
+          (@env['SCRIPT_NAME'].to_s + @env['PATH_INFO'].to_s) == uri
         end
 
         def nonce
diff --git a/lib/rack/auth/openid.rb b/lib/rack/auth/openid.rb
index de8babce..43cbe4f9 100644
--- a/lib/rack/auth/openid.rb
+++ b/lib/rack/auth/openid.rb
@@ -89,7 +89,7 @@ module Rack
     # The first argument is an OpenID::Response, the second is a
     # Rack::Request of the current request, the last is the hash used in
     # ruby-openid handling, which can be found manually at
-    # env[Const::RACK_SESSION][:openid].
+    # env['rack.session'][:openid].
     #
     # This is useful if you wanted to expand the processing done, such as
     # setting up user accounts.
@@ -98,7 +98,7 @@ module Rack
     #   def oid_app.success oid, request, session
     #     user = Models::User[oid.identity_url]
     #     user ||= Models::User.create_from_openid oid
-    #     request[Const::RACK_SESSION][:user] = user.id
+    #     request['rack.session'][:user] = user.id
     #     redirect MyApp.site_home
     #   end
     #
@@ -133,7 +133,7 @@ module Rack
       # the current request is used.
       #
       # <tt>:session_key</tt> defines the key to the session hash in the env.
-      # The default is Const::RACK_SESSION.
+      # The default is 'rack.session'.
       #
       # <tt>:openid_param</tt> defines at what key in the request parameters to
       # find the identifier to resolve. As per the 2.0 spec, the default is
@@ -159,7 +159,7 @@ module Rack
           and realm.fragment.nil? \
           and realm.scheme =~ /^https?$/ \
           and realm.host =~ /^(\*\.)?#{URI::REGEXP::PATTERN::URIC_NO_SLASH}+/
-        realm.path = Const::SLASH if realm.path.empty?
+        realm.path = '/' if realm.path.empty?
         @realm = realm.to_s
 
         if ruri = options[:return_to]
@@ -173,7 +173,7 @@ module Rack
           @return_to = ruri.to_s
         end
 
-        @session_key  = options[:session_key]   || Const::RACK_SESSION
+        @session_key  = options[:session_key]   || 'rack.session'
         @openid_param = options[:openid_param]  || 'openid_identifier'
         @store        = options[:store]         || ::OpenID::Store::Memory.new
         @immediate    = !!options[:immediate]
@@ -235,7 +235,7 @@ module Rack
       # If all parameters fit within the max length of a URI, a 303 redirect
       # will be returned. Otherwise #confirm_post_params will be called.
       #
-      # Any messages from OpenID's request are logged to env[Const::RACK_ERRORS]
+      # Any messages from OpenID's request are logged to env['rack.errors']
       #
       # <tt>env['rack.auth.openid.request']</tt> is the openid checkid request
       # instance.
@@ -249,7 +249,7 @@ module Rack
       def check(consumer, session, req)
         oid = consumer.begin(req.GET[@openid_param], @anonymous)
         req.env['rack.auth.openid.request'] = oid
-        req.env[Const::RACK_ERRORS].puts(oid.message)
+        req.env['rack.errors'].puts(oid.message)
         p oid if $DEBUG
 
         ## Extension support
@@ -269,7 +269,7 @@ module Rack
         end
       rescue ::OpenID::DiscoveryFailure => e
         # thrown from inside OpenID::Consumer#begin by yadis stuff
-        req.env[Const::RACK_ERRORS].puts( [e.message, *e.backtrace]*"\n" )
+        req.env['rack.errors'].puts( [e.message, *e.backtrace]*"\n" )
         return foreign_server_failure
       end
 
@@ -278,7 +278,7 @@ module Rack
       # Data gathered from extensions are stored in session[:openid] with the
       # extension's namespace uri as the key.
       #
-      # Any messages from OpenID's response are logged to env[Const::RACK_ERRORS]
+      # Any messages from OpenID's response are logged to env['rack.errors']
       #
       # <tt>env['rack.auth.openid.response']</tt> will contain the openid
       # response.
@@ -286,7 +286,7 @@ module Rack
       def finish(consumer, session, req)
         oid = consumer.complete(req.GET, req.url)
         req.env['rack.auth.openid.response'] = oid
-        req.env[Const::RACK_ERRORS].puts(oid.message)
+        req.env['rack.errors'].puts(oid.message)
         p oid if $DEBUG
 
         if ValidStatus.include?(oid.status)
@@ -366,7 +366,7 @@ module Rack
       # argument.
 
       def redirect(uri)
-        [ 303, {Const::CONTENT_TYPE=>'text/plain', Const::CONTENT_LENGTH=>'0',
+        [ 303, {'Content-Type'=>'text/plain', 'Content-Length'=>'0',
           'Location' => uri},
           [] ]
       end
@@ -374,21 +374,21 @@ module Rack
       # Returns an empty 400 response.
 
       def bad_request
-        [ 400, {Const::CONTENT_TYPE=>'text/plain', Const::CONTENT_LENGTH=>'0'},
+        [ 400, {'Content-Type'=>'text/plain', 'Content-Length'=>'0'},
           [''] ]
       end
 
       # Returns a basic unauthorized 401 response.
 
       def unauthorized
-        [ 401, {Const::CONTENT_TYPE => 'text/plain', Const::CONTENT_LENGTH => '13'},
+        [ 401, {'Content-Type' => 'text/plain', 'Content-Length' => '13'},
           ['Unauthorized.'] ]
       end
 
       # Returns a basic access denied 403 response.
 
       def access_denied
-        [ 403, {Const::CONTENT_TYPE => 'text/plain', Const::CONTENT_LENGTH => '14'},
+        [ 403, {'Content-Type' => 'text/plain', 'Content-Length' => '14'},
           ['Access denied.'] ]
       end
 
@@ -396,7 +396,7 @@ module Rack
       # OpenID server fails.
 
       def foreign_server_failure
-        [ 503, {Const::CONTENT_TYPE=>'text/plain', Const::CONTENT_LENGTH => '23'},
+        [ 503, {'Content-Type'=>'text/plain', 'Content-Length' => '23'},
           ['Foreign server failure.'] ]
       end
 
@@ -452,7 +452,7 @@ module Rack
       def invalid_status(oid, request, session)
         msg = 'Invalid status returned by the OpenID authorization reponse.'
         [ 500,
-          {Const::CONTENT_TYPE=>'text/plain',Const::CONTENT_LENGTH=>msg.length.to_s},
+          {'Content-Type'=>'text/plain','Content-Length'=>msg.length.to_s},
           [msg] ]
       end
     end
@@ -463,7 +463,7 @@ module Rack
     #
     #   use Rack::Session::Pool
     #   use Rack::Auth::OpenIDAuth, realm, openid_options do |env|
-    #     env[Const::RACK_SESSION][:authkey] == a_string
+    #     env['rack.session'][:authkey] == a_string
     #   end
     #   run RackApp
     #
diff --git a/lib/rack/builder.rb b/lib/rack/builder.rb
index 84257b4d..295235e5 100644
--- a/lib/rack/builder.rb
+++ b/lib/rack/builder.rb
@@ -17,7 +17,7 @@ module Rack
   #
   #  app = Rack::Builder.app do
   #    use Rack::CommonLogger
-  #    lambda { |env| [200, {Const::CONTENT_TYPE => 'text/plain'}, 'OK'] }
+  #    lambda { |env| [200, {'Content-Type' => 'text/plain'}, 'OK'] }
   #  end
   #
   # +use+ adds a middleware to the stack, +run+ dispatches to an application.
diff --git a/lib/rack/chunked.rb b/lib/rack/chunked.rb
index e0d88bac..280d89dd 100644
--- a/lib/rack/chunked.rb
+++ b/lib/rack/chunked.rb
@@ -15,10 +15,10 @@ module Rack
       status, headers, body = @app.call(env)
       headers = HeaderHash.new(headers)
 
-      if env[Const::ENV_HTTP_VERSION] == 'HTTP/1.0' ||
+      if env['HTTP_VERSION'] == 'HTTP/1.0' ||
          STATUS_WITH_NO_ENTITY_BODY.include?(status) ||
-         headers[Const::CONTENT_LENGTH] ||
-         headers[Const::TRANSFER_ENCODING]
+         headers['Content-Length'] ||
+         headers['Transfer-Encoding']
         [status, headers.to_hash, body]
       else
         dup.chunk(status, headers, body)
@@ -27,8 +27,8 @@ module Rack
 
     def chunk(status, headers, body)
       @body = body
-      headers.delete(Const::CONTENT_LENGTH)
-      headers[Const::TRANSFER_ENCODING] = 'chunked'
+      headers.delete('Content-Length')
+      headers['Transfer-Encoding'] = 'chunked'
       [status, headers.to_hash, self]
     end
 
diff --git a/lib/rack/commonlogger.rb b/lib/rack/commonlogger.rb
index 26e0a260..880f0fbf 100644
--- a/lib/rack/commonlogger.rb
+++ b/lib/rack/commonlogger.rb
@@ -26,15 +26,15 @@ module Rack
       now = Time.now
       length = extract_content_length(header)
 
-      logger = @logger || env[Const::RACK_ERRORS]
+      logger = @logger || env['rack.errors']
       logger.write FORMAT % [
-        env[Const::ENV_HTTP_X_FORWARDED_FOR] || env[Const::ENV_REMOTE_ADDR] || "-",
-        env[Const::ENV_REMOTE_USER] || "-",
+        env['HTTP_X_FORWARDED_FOR'] || env["REMOTE_ADDR"] || "-",
+        env["REMOTE_USER"] || "-",
         now.strftime("%d/%b/%Y %H:%M:%S"),
-        env[Const::ENV_REQUEST_METHOD],
-        env[Const::ENV_PATH_INFO],
-        env[Const::ENV_QUERY_STRING].empty? ? Const::EMPTY_STRING : "?"+env[Const::ENV_QUERY_STRING],
-        env[Const::ENV_HTTP_VERSION],
+        env["REQUEST_METHOD"],
+        env["PATH_INFO"],
+        env["QUERY_STRING"].empty? ? "" : "?"+env["QUERY_STRING"],
+        env["HTTP_VERSION"],
         status.to_s[0..3],
         length,
         now - began_at ]
diff --git a/lib/rack/conditionalget.rb b/lib/rack/conditionalget.rb
index 166c1930..046ebdb0 100644
--- a/lib/rack/conditionalget.rb
+++ b/lib/rack/conditionalget.rb
@@ -20,14 +20,14 @@ module Rack
     end
 
     def call(env)
-      return @app.call(env) unless %w[GET HEAD].include?(env[Const::ENV_REQUEST_METHOD])
+      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(Const::CONTENT_TYPE)
-        headers.delete(Const::CONTENT_LENGTH)
+        headers.delete('Content-Type')
+        headers.delete('Content-Length')
         body = []
       end
       [status, headers, body]
@@ -35,12 +35,12 @@ module Rack
 
   private
     def etag_matches?(env, headers)
-      etag = headers[Const::ETAG] and etag == env[Const::ENV_HTTP_IF_NONE_MATCH]
+      etag = headers['Etag'] and etag == env['HTTP_IF_NONE_MATCH']
     end
 
     def modified_since?(env, headers)
-      last_modified = headers[Const::LAST_MODIFIED] and
-        last_modified == env[Const::ENV_HTTP_IF_MODIFIED_SINCE]
+      last_modified = headers['Last-Modified'] and
+        last_modified == env['HTTP_IF_MODIFIED_SINCE']
     end
   end
 
diff --git a/lib/rack/constants.rb b/lib/rack/constants.rb
deleted file mode 100644
index 8c9afeda..00000000
--- a/lib/rack/constants.rb
+++ /dev/null
@@ -1,55 +0,0 @@
-module Rack
-  module Const
-    RACK_VERSION         = 'rack.version'.freeze
-    RACK_INPUT           = 'rack.input'.freeze
-    RACK_ERRORS          = 'rack.errors'.freeze
-    RACK_MULTITHREAD     = 'rack.multithread'.freeze
-    RACK_MULTIPROCESS    = 'rack.multiprocess'.freeze
-    RACK_RUN_ONCE        = 'rack.run_once'.freeze
-    RACK_URL_SCHEME      = 'rack.url_scheme'.freeze
-    RACK_SESSION         = 'rack.session'.freeze
-    RACK_SESSION_OPTIONS = 'rack.session.options'.freeze
-
-    ENV_CONTENT_LENGTH         = 'CONTENT_LENGTH'.freeze
-    ENV_CONTENT_TYPE           = 'CONTENT_TYPE'.freeze
-    ENV_HTTPS                  = 'HTTPS'.freeze
-    ENV_HTTP_ACCEPT_ENCODING   = 'HTTP_ACCEPT_ENCODING'.freeze
-    ENV_HTTP_CONTENT_LENGTH    = 'HTTP_CONTENT_LENGTH'.freeze
-    ENV_HTTP_CONTENT_TYPE      = 'HTTP_CONTENT_TYPE'.freeze
-    ENV_HTTP_COOKIE            = 'HTTP_COOKIE'.freeze
-    ENV_HTTP_HOST              = 'HTTP_HOST'.freeze
-    ENV_HTTP_IF_MODIFIED_SINCE = 'HTTP_IF_MODIFIED_SINCE'.freeze
-    ENV_HTTP_IF_NONE_MATCH     = 'HTTP_IF_NONE_MATCH'.freeze
-    ENV_HTTP_PORT              = 'HTTP_PORT'.freeze
-    ENV_HTTP_REFERER           = 'HTTP_REFERER'.freeze
-    ENV_HTTP_VERSION           = 'HTTP_VERSION'.freeze
-    ENV_HTTP_X_FORWARDED_FOR   = 'HTTP_X_FORWARDED_FOR'.freeze
-    ENV_HTTP_X_REQUESTED_WITH  = 'HTTP_X_REQUESTED_WITH'.freeze
-    ENV_PATH_INFO              = 'PATH_INFO'.freeze
-    ENV_QUERY_STRING           = 'QUERY_STRING'.freeze
-    ENV_REMOTE_ADDR            = 'REMOTE_ADDR'.freeze
-    ENV_REMOTE_USER            = 'REMOTE_USER'.freeze
-    ENV_REQUEST_METHOD         = 'REQUEST_METHOD'.freeze
-    ENV_REQUEST_PATH           = 'REQUEST_PATH'.freeze
-    ENV_REQUEST_URI            = 'REQUEST_URI'.freeze
-    ENV_SCRIPT_NAME            = 'SCRIPT_NAME'.freeze
-    ENV_SERVER_NAME            = 'SERVER_NAME'.freeze
-    ENV_SERVER_PORT            = 'SERVER_PORT'.freeze
-    ENV_SERVER_PROTOCOL        = 'SERVER_PROTOCOL'.freeze
-
-    CACHE_CONTROL     = 'Cache-Control'.freeze
-    CONTENT_ENCODING  = 'Content-Encoding'.freeze
-    CONTENT_LENGTH    = 'Content-Length'.freeze
-    CONTENT_TYPE      = 'Content-Type'.freeze
-    DELETE            = 'DELETE'.freeze
-    EMPTY_STRING      = ''.freeze
-    ETAG              = 'Etag'.freeze
-    GET               = 'GET'.freeze
-    HEAD              = 'HEAD'.freeze
-    LAST_MODIFIED     = 'Last-Modified'.freeze
-    POST              = 'POST'.freeze
-    PUT               = 'PUT'.freeze
-    SLASH             = '/'.freeze
-    TRANSFER_ENCODING = 'Transfer-Encoding'.freeze
-  end
-end
diff --git a/lib/rack/content_length.rb b/lib/rack/content_length.rb
index a3761295..1e56d438 100644
--- a/lib/rack/content_length.rb
+++ b/lib/rack/content_length.rb
@@ -14,13 +14,13 @@ module Rack
       headers = HeaderHash.new(headers)
 
       if !STATUS_WITH_NO_ENTITY_BODY.include?(status) &&
-         !headers[Const::CONTENT_LENGTH] &&
-         !headers[Const::TRANSFER_ENCODING] &&
+         !headers['Content-Length'] &&
+         !headers['Transfer-Encoding'] &&
          (body.respond_to?(:to_ary) || body.respond_to?(:to_str))
 
         body = [body] if body.respond_to?(:to_str) # rack 0.4 compat
         length = body.to_ary.inject(0) { |len, part| len + bytesize(part) }
-        headers[Const::CONTENT_LENGTH] = length.to_s
+        headers['Content-Length'] = length.to_s
       end
 
       [status, headers, body]
diff --git a/lib/rack/content_type.rb b/lib/rack/content_type.rb
index 08fe44ff..0c1e1ca3 100644
--- a/lib/rack/content_type.rb
+++ b/lib/rack/content_type.rb
@@ -16,7 +16,7 @@ module Rack
     def call(env)
       status, headers, body = @app.call(env)
       headers = Utils::HeaderHash.new(headers)
-      headers[Const::CONTENT_TYPE] ||= @content_type
+      headers['Content-Type'] ||= @content_type
       [status, headers.to_hash, body]
     end
   end
diff --git a/lib/rack/deflater.rb b/lib/rack/deflater.rb
index c06af7c6..ad0f5316 100644
--- a/lib/rack/deflater.rb
+++ b/lib/rack/deflater.rb
@@ -16,7 +16,7 @@ module Rack
       # Skip compressing empty entity body responses and responses with
       # no-transform set.
       if Utils::STATUS_WITH_NO_ENTITY_BODY.include?(status) ||
-          headers[Const::CACHE_CONTROL].to_s =~ /\bno-transform\b/
+          headers['Cache-Control'].to_s =~ /\bno-transform\b/
         return [status, headers, body]
       end
 
@@ -33,20 +33,20 @@ module Rack
 
       case encoding
       when "gzip"
-        headers[Const::CONTENT_ENCODING] = "gzip"
-        headers.delete(Const::CONTENT_LENGTH)
-        mtime = headers.key?(Const::LAST_MODIFIED) ?
-          Time.httpdate(headers[Const::LAST_MODIFIED]) : Time.now
+        headers['Content-Encoding'] = "gzip"
+        headers.delete('Content-Length')
+        mtime = headers.key?("Last-Modified") ?
+          Time.httpdate(headers["Last-Modified"]) : Time.now
         [status, headers, GzipStream.new(body, mtime)]
       when "deflate"
-        headers[Const::CONTENT_ENCODING] = "deflate"
-        headers.delete(Const::CONTENT_LENGTH)
+        headers['Content-Encoding'] = "deflate"
+        headers.delete('Content-Length')
         [status, headers, DeflateStream.new(body)]
       when "identity"
         [status, headers, body]
       when nil
         message = "An acceptable encoding for the requested resource #{request.fullpath} could not be found."
-        [406, {Const::CONTENT_TYPE => "text/plain", Const::CONTENT_LENGTH => message.length.to_s}, [message]]
+        [406, {"Content-Type" => "text/plain", "Content-Length" => message.length.to_s}, [message]]
       end
     end
 
diff --git a/lib/rack/directory.rb b/lib/rack/directory.rb
index 15a35846..acdd3029 100644
--- a/lib/rack/directory.rb
+++ b/lib/rack/directory.rb
@@ -55,8 +55,8 @@ table { width:100%%; }
 
     def _call(env)
       @env = env
-      @script_name = env[Const::ENV_SCRIPT_NAME]
-      @path_info = Utils.unescape(env[Const::ENV_PATH_INFO])
+      @script_name = env['SCRIPT_NAME']
+      @path_info = Utils.unescape(env['PATH_INFO'])
 
       if forbidden = check_forbidden
         forbidden
@@ -71,7 +71,7 @@ table { width:100%%; }
 
       body = "Forbidden\n"
       size = Rack::Utils.bytesize(body)
-      return [403, {Const::CONTENT_TYPE => "text/plain",Const::CONTENT_LENGTH => size.to_s}, [body]]
+      return [403, {"Content-Type" => "text/plain","Content-Length" => size.to_s}, [body]]
     end
 
     def list_directory
@@ -95,7 +95,7 @@ table { width:100%%; }
         @files << [ url, basename, size, type, mtime ]
       end
 
-      return [ 200, {Const::CONTENT_TYPE=>'text/html; charset=utf-8'}, self ]
+      return [ 200, {'Content-Type'=>'text/html; charset=utf-8'}, self ]
     end
 
     def stat(node, max = 10)
@@ -123,7 +123,7 @@ table { width:100%%; }
     def entity_not_found
       body = "Entity not found: #{@path_info}\n"
       size = Rack::Utils.bytesize(body)
-      return [404, {Const::CONTENT_TYPE => "text/plain", Const::CONTENT_LENGTH => size.to_s}, [body]]
+      return [404, {"Content-Type" => "text/plain", "Content-Length" => size.to_s}, [body]]
     end
 
     def each
diff --git a/lib/rack/file.rb b/lib/rack/file.rb
index 13b16536..fe62bd6b 100644
--- a/lib/rack/file.rb
+++ b/lib/rack/file.rb
@@ -26,7 +26,7 @@ module Rack
     F = ::File
 
     def _call(env)
-      @path_info = Utils.unescape(env[Const::ENV_PATH_INFO])
+      @path_info = Utils.unescape(env["PATH_INFO"])
       return forbidden  if @path_info.include? ".."
 
       @path = F.join(@root, @path_info)
@@ -44,8 +44,8 @@ module Rack
 
     def forbidden
       body = "Forbidden\n"
-      [403, {Const::CONTENT_TYPE => "text/plain",
-             Const::CONTENT_LENGTH => body.size.to_s},
+      [403, {"Content-Type" => "text/plain",
+             "Content-Length" => body.size.to_s},
        [body]]
     end
 
@@ -64,16 +64,16 @@ module Rack
       end
 
       [200, {
-        Const::LAST_MODIFIED  => F.mtime(@path).httpdate,
-        Const::CONTENT_TYPE   => Mime.mime_type(F.extname(@path), 'text/plain'),
-        Const::CONTENT_LENGTH => size.to_s
+        "Last-Modified"  => F.mtime(@path).httpdate,
+        "Content-Type"   => Mime.mime_type(F.extname(@path), 'text/plain'),
+        "Content-Length" => size.to_s
       }, body]
     end
 
     def not_found
       body = "File not found: #{@path_info}\n"
-      [404, {Const::CONTENT_TYPE => "text/plain",
-         Const::CONTENT_LENGTH => body.size.to_s},
+      [404, {"Content-Type" => "text/plain",
+         "Content-Length" => body.size.to_s},
        [body]]
     end
 
diff --git a/lib/rack/handler/cgi.rb b/lib/rack/handler/cgi.rb
index 9ba2572a..f45f3d73 100644
--- a/lib/rack/handler/cgi.rb
+++ b/lib/rack/handler/cgi.rb
@@ -11,24 +11,24 @@ module Rack
         app = ContentLength.new(app)
 
         env = ENV.to_hash
-        env.delete Const::ENV_HTTP_CONTENT_LENGTH
+        env.delete "HTTP_CONTENT_LENGTH"
 
-        env[Const::ENV_SCRIPT_NAME] = ""  if env[Const::ENV_SCRIPT_NAME] == "/"
+        env["SCRIPT_NAME"] = ""  if env["SCRIPT_NAME"] == "/"
 
-        env.update({Const::RACK_VERSION => [1,0],
-                     Const::RACK_INPUT => $stdin,
-                     Const::RACK_ERRORS => $stderr,
+        env.update({"rack.version" => [1,0],
+                     "rack.input" => $stdin,
+                     "rack.errors" => $stderr,
 
-                     Const::RACK_MULTITHREAD => false,
-                     Const::RACK_MULTIPROCESS => true,
-                     Const::RACK_RUN_ONCE => true,
+                     "rack.multithread" => false,
+                     "rack.multiprocess" => true,
+                     "rack.run_once" => true,
 
-                     Const::RACK_URL_SCHEME => ["yes", "on", "1"].include?(ENV[Const::ENV_HTTPS]) ? "https" : "http"
+                     "rack.url_scheme" => ["yes", "on", "1"].include?(ENV["HTTPS"]) ? "https" : "http"
                    })
 
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env[Const::ENV_HTTP_VERSION] ||= env[Const::ENV_SERVER_PROTOCOL]
-        env[Const::ENV_REQUEST_PATH] ||= "/"
+        env["QUERY_STRING"] ||= ""
+        env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
+        env["REQUEST_PATH"] ||= "/"
 
         status, headers, body = app.call(env)
         begin
diff --git a/lib/rack/handler/fastcgi.rb b/lib/rack/handler/fastcgi.rb
index 0cf7a439..11e1fcaa 100644
--- a/lib/rack/handler/fastcgi.rb
+++ b/lib/rack/handler/fastcgi.rb
@@ -28,29 +28,29 @@ module Rack
         app = Rack::ContentLength.new(app)
 
         env = request.env
-        env.delete Const::ENV_HTTP_CONTENT_LENGTH
+        env.delete "HTTP_CONTENT_LENGTH"
 
-        env[Const::ENV_SCRIPT_NAME] = ""  if env[Const::ENV_SCRIPT_NAME] == "/"
+        env["SCRIPT_NAME"] = ""  if env["SCRIPT_NAME"] == "/"
         
         rack_input = RewindableInput.new(request.in)
 
-        env.update({Const::RACK_VERSION => [1,0],
-                     Const::RACK_INPUT => rack_input,
-                     Const::RACK_ERRORS => request.err,
+        env.update({"rack.version" => [1,0],
+                     "rack.input" => rack_input,
+                     "rack.errors" => request.err,
 
-                     Const::RACK_MULTITHREAD => false,
-                     Const::RACK_MULTIPROCESS => true,
-                     Const::RACK_RUN_ONCE => false,
+                     "rack.multithread" => false,
+                     "rack.multiprocess" => true,
+                     "rack.run_once" => false,
 
-                     Const::RACK_URL_SCHEME => ["yes", "on", "1"].include?(env[Const::ENV_HTTPS]) ? "https" : "http"
+                     "rack.url_scheme" => ["yes", "on", "1"].include?(env["HTTPS"]) ? "https" : "http"
                    })
 
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env[Const::ENV_HTTP_VERSION] ||= env[Const::ENV_SERVER_PROTOCOL]
-        env[Const::ENV_REQUEST_PATH] ||= "/"
-        env.delete Const::ENV_PATH_INFO  if env[Const::ENV_PATH_INFO] == ""
-        env.delete Const::ENV_CONTENT_TYPE  if env[Const::ENV_CONTENT_TYPE] == ""
-        env.delete Const::ENV_CONTENT_LENGTH  if env[Const::ENV_CONTENT_LENGTH] == ""
+        env["QUERY_STRING"] ||= ""
+        env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
+        env["REQUEST_PATH"] ||= "/"
+        env.delete "PATH_INFO"  if env["PATH_INFO"] == ""
+        env.delete "CONTENT_TYPE"  if env["CONTENT_TYPE"] == ""
+        env.delete "CONTENT_LENGTH"  if env["CONTENT_LENGTH"] == ""
 
         begin
           status, headers, body = app.call(env)
diff --git a/lib/rack/handler/lsws.rb b/lib/rack/handler/lsws.rb
index 71f41bf2..b4ddf4bb 100644
--- a/lib/rack/handler/lsws.rb
+++ b/lib/rack/handler/lsws.rb
@@ -13,24 +13,24 @@ module Rack
         app = Rack::ContentLength.new(app)
 
         env = ENV.to_hash
-        env.delete Const::ENV_HTTP_CONTENT_LENGTH
-        env[Const::ENV_SCRIPT_NAME] = "" if env[Const::ENV_SCRIPT_NAME] == "/"
+        env.delete "HTTP_CONTENT_LENGTH"
+        env["SCRIPT_NAME"] = "" if env["SCRIPT_NAME"] == "/"
 
         rack_input = RewindableInput.new($stdin.read.to_s)
 
         env.update(
-          Const::RACK_VERSION => [1,0],
-          Const::RACK_INPUT => rack_input,
-          Const::RACK_ERRORS => $stderr,
-          Const::RACK_MULTITHREAD => false,
-          Const::RACK_MULTIPROCESS => true,
-          Const::RACK_RUN_ONCE => false,
-          Const::RACK_URL_SCHEME => ["yes", "on", "1"].include?(ENV[Const::ENV_HTTPS]) ? "https" : "http"
+          "rack.version" => [1,0],
+          "rack.input" => rack_input,
+          "rack.errors" => $stderr,
+          "rack.multithread" => false,
+          "rack.multiprocess" => true,
+          "rack.run_once" => false,
+          "rack.url_scheme" => ["yes", "on", "1"].include?(ENV["HTTPS"]) ? "https" : "http"
         )
 
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env[Const::ENV_HTTP_VERSION] ||= env[Const::ENV_SERVER_PROTOCOL]
-        env[Const::ENV_REQUEST_PATH] ||= "/"
+        env["QUERY_STRING"] ||= ""
+        env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
+        env["REQUEST_PATH"] ||= "/"
         status, headers, body = app.call(env)
         begin
           send_headers status, headers
diff --git a/lib/rack/handler/mongrel.rb b/lib/rack/handler/mongrel.rb
index ee11017b..7b448261 100644
--- a/lib/rack/handler/mongrel.rb
+++ b/lib/rack/handler/mongrel.rb
@@ -40,26 +40,26 @@ module Rack
 
       def process(request, response)
         env = {}.replace(request.params)
-        env.delete Const::ENV_HTTP_CONTENT_TYPE
-        env.delete Const::ENV_HTTP_CONTENT_LENGTH
+        env.delete "HTTP_CONTENT_TYPE"
+        env.delete "HTTP_CONTENT_LENGTH"
 
-        env[Const::ENV_SCRIPT_NAME] = ""  if env[Const::ENV_SCRIPT_NAME] == "/"
+        env["SCRIPT_NAME"] = ""  if env["SCRIPT_NAME"] == "/"
 
         rack_input = request.body || StringIO.new('')
         rack_input.set_encoding(Encoding::BINARY) if rack_input.respond_to?(:set_encoding)
 
-        env.update({Const::RACK_VERSION => [1,0],
-                     Const::RACK_INPUT => rack_input,
-                     Const::RACK_ERRORS => $stderr,
+        env.update({"rack.version" => [1,0],
+                     "rack.input" => rack_input,
+                     "rack.errors" => $stderr,
 
-                     Const::RACK_MULTITHREAD => true,
-                     Const::RACK_MULTIPROCESS => false, # ???
-                     Const::RACK_RUN_ONCE => false,
+                     "rack.multithread" => true,
+                     "rack.multiprocess" => false, # ???
+                     "rack.run_once" => false,
 
-                     Const::RACK_URL_SCHEME => "http",
+                     "rack.url_scheme" => "http",
                    })
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env.delete Const::ENV_PATH_INFO  if env[Const::ENV_PATH_INFO] == ""
+        env["QUERY_STRING"] ||= ""
+        env.delete "PATH_INFO"  if env["PATH_INFO"] == ""
 
         status, headers, body = @app.call(env)
 
diff --git a/lib/rack/handler/scgi.rb b/lib/rack/handler/scgi.rb
index 5c78977f..bd860a5d 100644
--- a/lib/rack/handler/scgi.rb
+++ b/lib/rack/handler/scgi.rb
@@ -25,25 +25,25 @@ module Rack
         
       def process_request(request, input_body, socket)
         env = {}.replace(request)
-        env.delete Const::ENV_HTTP_CONTENT_TYPE
-        env.delete Const::ENV_HTTP_CONTENT_LENGTH
-        env[Const::ENV_REQUEST_PATH], env[Const::ENV_QUERY_STRING] = env[Const::ENV_REQUEST_URI].split('?', 2)
-        env[Const::ENV_HTTP_VERSION] ||= env[Const::ENV_SERVER_PROTOCOL]
-        env[Const::ENV_PATH_INFO] = env[Const::ENV_REQUEST_PATH]
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env[Const::ENV_SCRIPT_NAME] = ""
+        env.delete "HTTP_CONTENT_TYPE"
+        env.delete "HTTP_CONTENT_LENGTH"
+        env["REQUEST_PATH"], env["QUERY_STRING"] = env["REQUEST_URI"].split('?', 2)
+        env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
+        env["PATH_INFO"] = env["REQUEST_PATH"]
+        env["QUERY_STRING"] ||= ""
+        env["SCRIPT_NAME"] = ""
 
         rack_input = StringIO.new(input_body)
         rack_input.set_encoding(Encoding::BINARY) if rack_input.respond_to?(:set_encoding)
 
-        env.update({Const::RACK_VERSION => [1,0],
-                     Const::RACK_INPUT => rack_input,
-                     Const::RACK_ERRORS => $stderr,
-                     Const::RACK_MULTITHREAD => true,
-                     Const::RACK_MULTIPROCESS => true,
-                     Const::RACK_RUN_ONCE => false,
+        env.update({"rack.version" => [1,0],
+                     "rack.input" => rack_input,
+                     "rack.errors" => $stderr,
+                     "rack.multithread" => true,
+                     "rack.multiprocess" => true,
+                     "rack.run_once" => false,
 
-                     Const::RACK_URL_SCHEME => ["yes", "on", "1"].include?(env[Const::ENV_HTTPS]) ? "https" : "http"
+                     "rack.url_scheme" => ["yes", "on", "1"].include?(env["HTTPS"]) ? "https" : "http"
                    })
         status, headers, body = app.call(env)
         begin
diff --git a/lib/rack/handler/webrick.rb b/lib/rack/handler/webrick.rb
index d4bebf43..5b9ae740 100644
--- a/lib/rack/handler/webrick.rb
+++ b/lib/rack/handler/webrick.rb
@@ -26,25 +26,25 @@ module Rack
         rack_input = StringIO.new(req.body.to_s)
         rack_input.set_encoding(Encoding::BINARY) if rack_input.respond_to?(:set_encoding)
 
-        env.update({Const::RACK_VERSION => [1,0],
-                     Const::RACK_INPUT => rack_input,
-                     Const::RACK_ERRORS => $stderr,
+        env.update({"rack.version" => [1,0],
+                     "rack.input" => rack_input,
+                     "rack.errors" => $stderr,
 
-                     Const::RACK_MULTITHREAD => true,
-                     Const::RACK_MULTIPROCESS => false,
-                     Const::RACK_RUN_ONCE => false,
+                     "rack.multithread" => true,
+                     "rack.multiprocess" => false,
+                     "rack.run_once" => false,
 
-                     Const::RACK_URL_SCHEME => ["yes", "on", "1"].include?(ENV[Const::ENV_HTTPS]) ? "https" : "http"
+                     "rack.url_scheme" => ["yes", "on", "1"].include?(ENV["HTTPS"]) ? "https" : "http"
                    })
 
-        env[Const::ENV_HTTP_VERSION] ||= env[Const::ENV_SERVER_PROTOCOL]
-        env[Const::ENV_QUERY_STRING] ||= ""
-        env[Const::ENV_REQUEST_PATH] ||= "/"
-        if env[Const::ENV_PATH_INFO] == ""
-          env.delete Const::ENV_PATH_INFO
+        env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
+        env["QUERY_STRING"] ||= ""
+        env["REQUEST_PATH"] ||= "/"
+        if env["PATH_INFO"] == ""
+          env.delete "PATH_INFO"
         else
-          path, n = req.request_uri.path, env[Const::ENV_SCRIPT_NAME].length
-          env[Const::ENV_PATH_INFO] = path[n, path.length-n]
+          path, n = req.request_uri.path, env["SCRIPT_NAME"].length
+          env["PATH_INFO"] = path[n, path.length-n]
         end
 
         status, headers, body = @app.call(env)
diff --git a/lib/rack/head.rb b/lib/rack/head.rb
index 825b5f51..deab822a 100644
--- a/lib/rack/head.rb
+++ b/lib/rack/head.rb
@@ -8,7 +8,7 @@ class Head
   def call(env)
     status, headers, body = @app.call(env)
 
-    if env[Const::ENV_REQUEST_METHOD] == Const::HEAD
+    if env["REQUEST_METHOD"] == "HEAD"
       [status, headers, []]
     else
       [status, headers, body]
diff --git a/lib/rack/lint.rb b/lib/rack/lint.rb
index 955ba2ec..796807a0 100644
--- a/lib/rack/lint.rb
+++ b/lib/rack/lint.rb
@@ -40,8 +40,8 @@ module Rack
       assert("No env given") { env }
       check_env env
 
-      env[Const::RACK_INPUT] = InputWrapper.new(env[Const::RACK_INPUT])
-      env[Const::RACK_ERRORS] = ErrorWrapper.new(env[Const::RACK_ERRORS])
+      env['rack.input'] = InputWrapper.new(env['rack.input'])
+      env['rack.errors'] = ErrorWrapper.new(env['rack.errors'])
 
       ## and returns an Array of exactly three values:
       status, headers, @body = @app.call(env)
@@ -126,7 +126,7 @@ module Rack
 
       ## <tt>rack.session</tt>:: A hash like interface for storing request session data.
       ##                         The store must implement:
-      if session = env[Const::RACK_SESSION]
+      if session = env['rack.session']
         ##                         store(key, value)         (aliased as []=);
         assert("session #{session.inspect} must respond to store and []=") {
           session.respond_to?(:store) && session.respond_to?(:[]=)
@@ -183,50 +183,50 @@ module Rack
       ## There are the following restrictions:
 
       ## * <tt>rack.version</tt> must be an array of Integers.
-      assert("rack.version must be an Array, was #{env[Const::RACK_VERSION].class}") {
-        env[Const::RACK_VERSION].instance_of? Array
+      assert("rack.version must be an Array, was #{env["rack.version"].class}") {
+        env["rack.version"].instance_of? Array
       }
       ## * <tt>rack.url_scheme</tt> must either be +http+ or +https+.
-      assert("rack.url_scheme unknown: #{env[Const::RACK_URL_SCHEME].inspect}") {
-        %w[http https].include? env[Const::RACK_URL_SCHEME]
+      assert("rack.url_scheme unknown: #{env["rack.url_scheme"].inspect}") {
+        %w[http https].include? env["rack.url_scheme"]
       }
 
       ## * There must be a valid input stream in <tt>rack.input</tt>.
-      check_input env[Const::RACK_INPUT]
+      check_input env["rack.input"]
       ## * There must be a valid error stream in <tt>rack.errors</tt>.
-      check_error env[Const::RACK_ERRORS]
+      check_error env["rack.errors"]
 
       ## * The <tt>REQUEST_METHOD</tt> must be a valid token.
-      assert("REQUEST_METHOD unknown: #{env[Const::ENV_REQUEST_METHOD]}") {
-        env[Const::ENV_REQUEST_METHOD] =~ /\A[0-9A-Za-z!\#$%&'*+.^_`|~-]+\z/
+      assert("REQUEST_METHOD unknown: #{env["REQUEST_METHOD"]}") {
+        env["REQUEST_METHOD"] =~ /\A[0-9A-Za-z!\#$%&'*+.^_`|~-]+\z/
       }
 
       ## * The <tt>SCRIPT_NAME</tt>, if non-empty, must start with <tt>/</tt>
       assert("SCRIPT_NAME must start with /") {
-        !env.include?(Const::ENV_SCRIPT_NAME) ||
-        env[Const::ENV_SCRIPT_NAME] == "" ||
-        env[Const::ENV_SCRIPT_NAME] =~ /\A\//
+        !env.include?("SCRIPT_NAME") ||
+        env["SCRIPT_NAME"] == "" ||
+        env["SCRIPT_NAME"] =~ /\A\//
       }
       ## * The <tt>PATH_INFO</tt>, if non-empty, must start with <tt>/</tt>
       assert("PATH_INFO must start with /") {
-        !env.include?(Const::ENV_PATH_INFO) ||
-        env[Const::ENV_PATH_INFO] == "" ||
-        env[Const::ENV_PATH_INFO] =~ /\A\//
+        !env.include?("PATH_INFO") ||
+        env["PATH_INFO"] == "" ||
+        env["PATH_INFO"] =~ /\A\//
       }
       ## * The <tt>CONTENT_LENGTH</tt>, if given, must consist of digits only.
-      assert("Invalid CONTENT_LENGTH: #{env[Const::ENV_CONTENT_LENGTH]}") {
-        !env.include?(Const::ENV_CONTENT_LENGTH) || env[Const::ENV_CONTENT_LENGTH] =~ /\A\d+\z/
+      assert("Invalid CONTENT_LENGTH: #{env["CONTENT_LENGTH"]}") {
+        !env.include?("CONTENT_LENGTH") || env["CONTENT_LENGTH"] =~ /\A\d+\z/
       }
 
       ## * One of <tt>SCRIPT_NAME</tt> or <tt>PATH_INFO</tt> must be
       ##   set.  <tt>PATH_INFO</tt> should be <tt>/</tt> if
       ##   <tt>SCRIPT_NAME</tt> is empty.
       assert("One of SCRIPT_NAME or PATH_INFO must be set (make PATH_INFO '/' if SCRIPT_NAME is empty)") {
-        env[Const::ENV_SCRIPT_NAME] || env[Const::ENV_PATH_INFO]
+        env["SCRIPT_NAME"] || env["PATH_INFO"]
       }
       ##   <tt>SCRIPT_NAME</tt> never should be <tt>/</tt>, but instead be empty.
       assert("SCRIPT_NAME cannot be '/', make it '' and PATH_INFO '/'") {
-        env[Const::ENV_SCRIPT_NAME] != "/"
+        env["SCRIPT_NAME"] != "/"
       }
     end
 
@@ -474,7 +474,7 @@ module Rack
               bytes += Rack::Utils.bytesize(part)
             }
 
-            if env[Const::ENV_REQUEST_METHOD] == Const::HEAD
+            if env["REQUEST_METHOD"] == "HEAD"
               assert("Response body was given for HEAD request, but should be empty") {
                 bytes == 0
               }
diff --git a/lib/rack/lobster.rb b/lib/rack/lobster.rb
index a434b850..f63f419a 100644
--- a/lib/rack/lobster.rb
+++ b/lib/rack/lobster.rb
@@ -12,7 +12,7 @@ module Rack
     I8jyiTlhTcYXkekJAzTyYN6E08A+dk8voBkAVTJQ==".delete("\n ").unpack("m*")[0])
 
     LambdaLobster = lambda { |env|
-      if env[Const::ENV_QUERY_STRING].include?("flip")
+      if env["QUERY_STRING"].include?("flip")
         lobster = LobsterString.split("\n").
           map { |line| line.ljust(42).reverse }.
           join("\n")
@@ -26,7 +26,7 @@ module Rack
                  "<pre>", lobster, "</pre>",
                  "<a href='#{href}'>flip!</a>"]
       length = content.inject(0) { |a,e| a+e.size }.to_s
-      [200, {Const::CONTENT_TYPE => "text/html", Const::CONTENT_LENGTH => length}, content]
+      [200, {"Content-Type" => "text/html", "Content-Length" => length}, content]
     }
 
     def call(env)
diff --git a/lib/rack/lock.rb b/lib/rack/lock.rb
index aa0cf7fd..93238528 100644
--- a/lib/rack/lock.rb
+++ b/lib/rack/lock.rb
@@ -1,6 +1,6 @@
 module Rack
   class Lock
-    FLAG = Const::RACK_MULTITHREAD.freeze
+    FLAG = 'rack.multithread'.freeze
 
     def initialize(app, lock = Mutex.new)
       @app, @lock = app, lock
diff --git a/lib/rack/methodoverride.rb b/lib/rack/methodoverride.rb
index e0dd1baa..0eed29f4 100644
--- a/lib/rack/methodoverride.rb
+++ b/lib/rack/methodoverride.rb
@@ -10,14 +10,14 @@ module Rack
     end
 
     def call(env)
-      if env[Const::ENV_REQUEST_METHOD] == Const::POST
+      if env["REQUEST_METHOD"] == "POST"
         req = Request.new(env)
         method = req.POST[METHOD_OVERRIDE_PARAM_KEY] ||
           env[HTTP_METHOD_OVERRIDE_HEADER]
         method = method.to_s.upcase
         if HTTP_METHODS.include?(method)
-          env["rack.methodoverride.original_method"] = env[Const::ENV_REQUEST_METHOD]
-          env[Const::ENV_REQUEST_METHOD] = method
+          env["rack.methodoverride.original_method"] = env["REQUEST_METHOD"]
+          env["REQUEST_METHOD"] = method
         end
       end
 
diff --git a/lib/rack/mock.rb b/lib/rack/mock.rb
index a4f89dd9..7964c447 100644
--- a/lib/rack/mock.rb
+++ b/lib/rack/mock.rb
@@ -1,6 +1,5 @@
 require 'uri'
 require 'stringio'
-require 'rack/constants'
 require 'rack/lint'
 require 'rack/utils'
 require 'rack/response'
@@ -41,24 +40,24 @@ module Rack
     end
 
     DEFAULT_ENV = {
-      Const::RACK_VERSION => [1,0],
-      Const::RACK_INPUT => StringIO.new,
-      Const::RACK_ERRORS => StringIO.new,
-      Const::RACK_MULTITHREAD => true,
-      Const::RACK_MULTIPROCESS => true,
-      Const::RACK_RUN_ONCE => false,
+      "rack.version" => [1,0],
+      "rack.input" => StringIO.new,
+      "rack.errors" => StringIO.new,
+      "rack.multithread" => true,
+      "rack.multiprocess" => true,
+      "rack.run_once" => false,
     }
 
     def initialize(app)
       @app = app
     end
 
-    def get(uri, opts={})    request(Const::GET, uri, opts)    end
-    def post(uri, opts={})   request(Const::POST, uri, opts)   end
-    def put(uri, opts={})    request(Const::PUT, uri, opts)    end
-    def delete(uri, opts={}) request(Const::DELETE, uri, opts) end
+    def get(uri, opts={})    request("GET", uri, opts)    end
+    def post(uri, opts={})   request("POST", uri, opts)   end
+    def put(uri, opts={})    request("PUT", uri, opts)    end
+    def delete(uri, opts={}) request("DELETE", uri, opts) end
 
-    def request(method=Const::GET, uri="", opts={})
+    def request(method="GET", uri="", opts={})
       env = self.class.env_for(uri, opts.merge(:method => method))
 
       if opts[:lint]
@@ -67,7 +66,7 @@ module Rack
         app = @app
       end
 
-      errors = env[Const::RACK_ERRORS]
+      errors = env["rack.errors"]
       MockResponse.new(*(app.call(env) + [errors]))
     end
 
@@ -78,34 +77,34 @@ module Rack
 
       env = DEFAULT_ENV.dup
 
-      env[Const::ENV_REQUEST_METHOD] = opts[:method] ? opts[:method].to_s.upcase : Const::GET
-      env[Const::ENV_SERVER_NAME] = uri.host || "example.org"
-      env[Const::ENV_SERVER_PORT] = uri.port ? uri.port.to_s : "80"
-      env[Const::ENV_QUERY_STRING] = uri.query.to_s
-      env[Const::ENV_PATH_INFO] = (!uri.path || uri.path.empty?) ? "/" : uri.path
-      env[Const::RACK_URL_SCHEME] = uri.scheme || "http"
-      env[Const::ENV_HTTPS] = env[Const::RACK_URL_SCHEME] == "https" ? "on" : "off"
+      env["REQUEST_METHOD"] = opts[:method] ? opts[:method].to_s.upcase : "GET"
+      env["SERVER_NAME"] = uri.host || "example.org"
+      env["SERVER_PORT"] = uri.port ? uri.port.to_s : "80"
+      env["QUERY_STRING"] = uri.query.to_s
+      env["PATH_INFO"] = (!uri.path || uri.path.empty?) ? "/" : uri.path
+      env["rack.url_scheme"] = uri.scheme || "http"
+      env["HTTPS"] = env["rack.url_scheme"] == "https" ? "on" : "off"
 
-      env[Const::ENV_SCRIPT_NAME] = opts[:script_name] || ""
+      env["SCRIPT_NAME"] = opts[:script_name] || ""
 
       if opts[:fatal]
-        env[Const::RACK_ERRORS] = FatalWarner.new
+        env["rack.errors"] = FatalWarner.new
       else
-        env[Const::RACK_ERRORS] = StringIO.new
+        env["rack.errors"] = StringIO.new
       end
 
       if params = opts[:params]
-        if env[Const::ENV_REQUEST_METHOD] == Const::GET
+        if env["REQUEST_METHOD"] == "GET"
           params = Utils.parse_nested_query(params) if params.is_a?(String)
-          params.update(Utils.parse_nested_query(env[Const::ENV_QUERY_STRING]))
-          env[Const::ENV_QUERY_STRING] = Utils.build_nested_query(params)
+          params.update(Utils.parse_nested_query(env["QUERY_STRING"]))
+          env["QUERY_STRING"] = Utils.build_nested_query(params)
         elsif !opts.has_key?(:input)
-          opts[Const::ENV_CONTENT_TYPE] = "application/x-www-form-urlencoded"
+          opts["CONTENT_TYPE"] = "application/x-www-form-urlencoded"
           if params.is_a?(Hash)
             if data = Utils::Multipart.build_multipart(params)
               opts[:input] = data
-              opts[Const::ENV_CONTENT_LENGTH] ||= data.length.to_s
-              opts[Const::ENV_CONTENT_TYPE] = "multipart/form-data; boundary=#{Utils::Multipart::MULTIPART_BOUNDARY}"
+              opts["CONTENT_LENGTH"] ||= data.length.to_s
+              opts["CONTENT_TYPE"] = "multipart/form-data; boundary=#{Utils::Multipart::MULTIPART_BOUNDARY}"
             else
               opts[:input] = Utils.build_nested_query(params)
             end
@@ -125,9 +124,9 @@ module Rack
       end
 
       rack_input.set_encoding(Encoding::BINARY) if rack_input.respond_to?(:set_encoding)
-      env[Const::RACK_INPUT] = rack_input
+      env['rack.input'] = rack_input
 
-      env[Const::ENV_CONTENT_LENGTH] ||= env[Const::RACK_INPUT].length.to_s
+      env["CONTENT_LENGTH"] ||= env["rack.input"].length.to_s
 
       opts.each { |field, value|
         env[field] = value  if String === field
diff --git a/lib/rack/recursive.rb b/lib/rack/recursive.rb
index d6c9a777..bf8b9659 100644
--- a/lib/rack/recursive.rb
+++ b/lib/rack/recursive.rb
@@ -14,11 +14,11 @@ module Rack
       @url = URI(url)
       @env = env
 
-      @env[Const::ENV_PATH_INFO] =       @url.path
-      @env[Const::ENV_QUERY_STRING] =    @url.query  if @url.query
-      @env[Const::ENV_HTTP_HOST] =       @url.host   if @url.host
-      @env[Const::ENV_HTTP_PORT] =       @url.port   if @url.port
-      @env[Const::RACK_URL_SCHEME] = @url.scheme if @url.scheme
+      @env["PATH_INFO"] =       @url.path
+      @env["QUERY_STRING"] =    @url.query  if @url.query
+      @env["HTTP_HOST"] =       @url.host   if @url.host
+      @env["HTTP_PORT"] =       @url.port   if @url.port
+      @env["rack.url_scheme"] = @url.scheme if @url.scheme
 
       super "forwarding to #{url}"
     end
@@ -35,7 +35,7 @@ module Rack
     end
 
     def call(env)
-      @script_name = env[Const::ENV_SCRIPT_NAME]
+      @script_name = env["SCRIPT_NAME"]
       @app.call(env.merge('rack.recursive.include' => method(:include)))
     rescue ForwardRequest => req
       call(env.merge(req.env))
@@ -47,10 +47,10 @@ module Rack
         raise ArgumentError, "can only include below #{@script_name}, not #{path}"
       end
 
-      env = env.merge(Const::ENV_PATH_INFO => path, Const::ENV_SCRIPT_NAME => @script_name,
-                      Const::ENV_REQUEST_METHOD => Const::GET,
-                      Const::ENV_CONTENT_LENGTH => "0", Const::ENV_CONTENT_TYPE => "",
-                      Const::RACK_INPUT => StringIO.new(""))
+      env = env.merge("PATH_INFO" => path, "SCRIPT_NAME" => @script_name,
+                      "REQUEST_METHOD" => "GET",
+                      "CONTENT_LENGTH" => "0", "CONTENT_TYPE" => "",
+                      "rack.input" => StringIO.new(""))
       @app.call(env)
     end
   end
diff --git a/lib/rack/request.rb b/lib/rack/request.rb
index 5188fc16..248ce18d 100644
--- a/lib/rack/request.rb
+++ b/lib/rack/request.rb
@@ -21,17 +21,17 @@ module Rack
       @env = env
     end
 
-    def body;            @env[Const::RACK_INPUT]                  end
-    def scheme;          @env[Const::RACK_URL_SCHEME]             end
-    def script_name;     @env[Const::ENV_SCRIPT_NAME].to_s            end
-    def path_info;       @env[Const::ENV_PATH_INFO].to_s              end
-    def port;            @env[Const::ENV_SERVER_PORT].to_i            end
-    def request_method;  @env[Const::ENV_REQUEST_METHOD]              end
-    def query_string;    @env[Const::ENV_QUERY_STRING].to_s           end
-    def content_length;  @env[Const::ENV_CONTENT_LENGTH]              end
-    def content_type;    @env[Const::ENV_CONTENT_TYPE]                end
-    def session;         @env[Const::RACK_SESSION] ||= {}         end
-    def session_options; @env[Const::RACK_SESSION_OPTIONS] ||= {} end
+    def body;            @env["rack.input"]                       end
+    def scheme;          @env["rack.url_scheme"]                  end
+    def script_name;     @env["SCRIPT_NAME"].to_s                 end
+    def path_info;       @env["PATH_INFO"].to_s                   end
+    def port;            @env["SERVER_PORT"].to_i                 end
+    def request_method;  @env["REQUEST_METHOD"]                   end
+    def query_string;    @env["QUERY_STRING"].to_s                end
+    def content_length;  @env['CONTENT_LENGTH']                   end
+    def content_type;    @env['CONTENT_TYPE']                     end
+    def session;         @env['rack.session'] ||= {}              end
+    def session_options; @env['rack.session.options'] ||= {}      end
 
     # The media type (type/subtype) portion of the CONTENT_TYPE header
     # without any media type parameters. e.g., when CONTENT_TYPE is
@@ -65,17 +65,17 @@ module Rack
 
     def host
       # Remove port number.
-      (@env[Const::ENV_HTTP_HOST] || @env[Const::ENV_SERVER_NAME]).to_s.gsub(/:\d+\z/, '')
+      (@env["HTTP_HOST"] || @env["SERVER_NAME"]).to_s.gsub(/:\d+\z/, '')
     end
 
-    def script_name=(s); @env[Const::ENV_SCRIPT_NAME] = s.to_s  end
-    def path_info=(s);   @env[Const::ENV_PATH_INFO] = s.to_s    end
+    def script_name=(s); @env["SCRIPT_NAME"] = s.to_s             end
+    def path_info=(s);   @env["PATH_INFO"] = s.to_s               end
 
-    def get?;            request_method == Const::GET           end
-    def post?;           request_method == Const::POST          end
-    def put?;            request_method == Const::PUT           end
-    def delete?;         request_method == Const::DELETE        end
-    def head?;           request_method == Const::HEAD          end
+    def get?;            request_method == "GET"                  end
+    def post?;           request_method == "POST"                 end
+    def put?;            request_method == "PUT"                  end
+    def delete?;         request_method == "DELETE"               end
+    def head?;           request_method == "HEAD"                 end
 
     # The set of form-data media-types. Requests that do not indicate
     # one of the media types presents in this list will not be eligible
@@ -109,46 +109,41 @@ module Rack
       PARSEABLE_DATA_MEDIA_TYPES.include?(media_type)
     end
 
-    QUERY_STRING = 'rack.request.query_string'.freeze
-    QUERY_HASH   = 'rack.request.query_hash'.freeze
-
     # Returns the data recieved in the query string.
     def GET
-      if @env[QUERY_STRING] == query_string
-        @env[QUERY_HASH]
+      if @env["rack.request.query_string"] == query_string
+        @env["rack.request.query_hash"]
       else
-        @env[QUERY_STRING] = query_string
-        @env[QUERY_HASH]   = Utils.parse_nested_query(query_string)
+        @env["rack.request.query_string"] = query_string
+        @env["rack.request.query_hash"]   =
+          Utils.parse_nested_query(query_string)
       end
     end
 
-    FORM_INPUT = 'rack.request.form_input'.freeze
-    FORM_HASH  = 'rack.request.form_hash'.freeze
-    FORM_VARS  = 'rack.request.form_vars'.freeze
-
     # Returns the data recieved in the request body.
     #
     # This method support both application/x-www-form-urlencoded and
     # multipart/form-data.
     def POST
-      if @env[Const::RACK_INPUT].nil?
+      if @env["rack.input"].nil?
         raise "Missing rack.input"
-      elsif @env[FORM_INPUT].eql? @env[Const::RACK_INPUT]
-        @env[FORM_HASH]
+      elsif @env["rack.request.form_input"].eql? @env["rack.input"]
+        @env["rack.request.form_hash"]
       elsif form_data? || parseable_data?
-        @env[FORM_INPUT] = @env[Const::RACK_INPUT]
-        unless @env[FORM_HASH] = Utils::Multipart.parse_multipart(env)
-          form_vars = @env[Const::RACK_INPUT].read
+        @env["rack.request.form_input"] = @env["rack.input"]
+        unless @env["rack.request.form_hash"] =
+            Utils::Multipart.parse_multipart(env)
+          form_vars = @env["rack.input"].read
 
           # Fix for Safari Ajax postings that always append \0
           form_vars.sub!(/\0\z/, '')
 
-          @env[FORM_VARS] = form_vars
-          @env[FORM_HASH] = Utils.parse_nested_query(form_vars)
+          @env["rack.request.form_vars"] = form_vars
+          @env["rack.request.form_hash"] = Utils.parse_nested_query(form_vars)
 
-          @env[Const::RACK_INPUT].rewind
+          @env["rack.input"].rewind
         end
-        @env[FORM_HASH]
+        @env["rack.request.form_hash"]
       else
         {}
       end
@@ -178,28 +173,25 @@ module Rack
 
     # the referer of the client or '/'
     def referer
-      @env[Const::ENV_HTTP_REFERER] || '/'
+      @env['HTTP_REFERER'] || '/'
     end
     alias referrer referer
 
 
-    COOKIE_STRING = 'rack.request.cookie_string'.freeze
-    COOKIE_HASH   = 'rack.request.cookie_hash'.freeze
-
     def cookies
-      return {}  unless @env[Const::ENV_HTTP_COOKIE]
+      return {}  unless @env["HTTP_COOKIE"]
 
-      if @env[COOKIE_STRING] == @env[Const::ENV_HTTP_COOKIE]
-        @env[COOKIE_HASH]
+      if @env["rack.request.cookie_string"] == @env["HTTP_COOKIE"]
+        @env["rack.request.cookie_hash"]
       else
-        @env[COOKIE_STRING] = @env[Const::ENV_HTTP_COOKIE]
+        @env["rack.request.cookie_string"] = @env["HTTP_COOKIE"]
         # According to RFC 2109:
         #   If multiple cookies satisfy the criteria above, they are ordered in
         #   the Cookie header such that those with more specific Path attributes
         #   precede those with less specific.  Ordering with respect to other
         #   attributes (e.g., Domain) is unspecified.
-        @env[COOKIE_HASH] =
-          Utils.parse_query(@env[COOKIE_STRING], ';,').inject({}) {|h,(k,v)|
+        @env["rack.request.cookie_hash"] =
+          Utils.parse_query(@env["rack.request.cookie_string"], ';,').inject({}) {|h,(k,v)|
             h[k] = Array === v ? v.first : v
             h
           }
@@ -207,7 +199,7 @@ module Rack
     end
 
     def xhr?
-      @env[Const::ENV_HTTP_X_REQUESTED_WITH] == "XMLHttpRequest"
+      @env["HTTP_X_REQUESTED_WITH"] == "XMLHttpRequest"
     end
 
     # Tries to return a remake of the original request URL as a string.
@@ -234,7 +226,7 @@ module Rack
     end
 
     def accept_encoding
-      @env[Const::ENV_HTTP_ACCEPT_ENCODING].to_s.split(/,\s*/).map do |part|
+      @env["HTTP_ACCEPT_ENCODING"].to_s.split(/,\s*/).map do |part|
         m = /^([^\s,]+?)(?:;\s*q=(\d+(?:\.\d+)?))?$/.match(part) # From WEBrick
 
         if m
@@ -246,10 +238,10 @@ module Rack
     end
 
     def ip
-      if addr = @env[Const::ENV_HTTP_X_FORWARDED_FOR]
+      if addr = @env['HTTP_X_FORWARDED_FOR']
         addr.split(',').last.strip
       else
-        @env[Const::ENV_REMOTE_ADDR]
+        @env['REMOTE_ADDR']
       end
     end
   end
diff --git a/lib/rack/response.rb b/lib/rack/response.rb
index 70d3e83e..d1f6a123 100644
--- a/lib/rack/response.rb
+++ b/lib/rack/response.rb
@@ -20,7 +20,7 @@ module Rack
 
     def initialize(body=[], status=200, header={}, &block)
       @status = status
-      @header = Utils::HeaderHash.new({Const::CONTENT_TYPE => "text/html"}.
+      @header = Utils::HeaderHash.new({"Content-Type" => "text/html"}.
                                       merge(header))
 
       @writer = lambda { |x| @body << x }
@@ -70,7 +70,7 @@ module Rack
       @block = block
 
       if [204, 304].include?(status.to_i)
-        header.delete Const::CONTENT_TYPE
+        header.delete "Content-Type"
         [status.to_i, header.to_hash, []]
       else
         [status.to_i, header.to_hash, self]
@@ -93,7 +93,7 @@ module Rack
       @length += Rack::Utils.bytesize(s)
       @writer.call s
 
-      header[Const::CONTENT_LENGTH] = @length.to_s
+      header["Content-Length"] = @length.to_s
       str
     end
 
@@ -131,11 +131,11 @@ module Rack
       end
 
       def content_type
-        headers[Const::CONTENT_TYPE]
+        headers["Content-Type"]
       end
 
       def content_length
-        cl = headers[Const::CONTENT_LENGTH]
+        cl = headers["Content-Length"]
         cl ? cl.to_i : cl
       end
 
diff --git a/lib/rack/session/abstract/id.rb b/lib/rack/session/abstract/id.rb
index ece97b52..98746705 100644
--- a/lib/rack/session/abstract/id.rb
+++ b/lib/rack/session/abstract/id.rb
@@ -18,7 +18,7 @@ module Rack
       #
       # All parameters are optional.
       # * :key determines the name of the cookie, by default it is
-      #   Const::RACK_SESSION
+      #   'rack.session'
       # * :path, :domain, :expire_after, :secure, and :httponly set the related
       #   cookie options as by Rack::Response#add_cookie
       # * :defer will not set a cookie in the response.
@@ -29,7 +29,7 @@ module Rack
       #   id will be.
       #
       # These options can be set on a per request basis, at the location of
-      # env[Const::RACK_SESSION_OPTIONS]. Additionally the id of the session can be
+      # env['rack.session.options']. Additionally the id of the session can be
       # found within the options hash at the key :id. It is highly not
       # recommended to change its value.
       #
@@ -50,7 +50,7 @@ module Rack
         attr_reader :key, :default_options
         def initialize(app, options={})
           @app = app
-          @key = options[:key] || Const::RACK_SESSION
+          @key = options[:key] || "rack.session"
           @default_options = self.class::DEFAULT_OPTIONS.merge(options)
         end
 
@@ -77,8 +77,8 @@ module Rack
 
         # Extracts the session id from provided cookies and passes it and the
         # environment to #get_session. It then sets the resulting session into
-        # Const::RACK_SESSION, and places options and session metadata into
-        # Const::RACK_SESSION_OPTIONS.
+        # 'rack.session', and places options and session metadata into
+        # 'rack.session.options'.
 
         def load_session(env)
           request = Rack::Request.new(env)
@@ -86,12 +86,12 @@ module Rack
 
           begin
             session_id, session = get_session(env, session_id)
-            env[Const::RACK_SESSION] = session
+            env['rack.session'] = session
           rescue
-            env[Const::RACK_SESSION] = Hash.new
+            env['rack.session'] = Hash.new
           end
 
-          env[Const::RACK_SESSION_OPTIONS] = @default_options.
+          env['rack.session.options'] = @default_options.
             merge(:id => session_id)
         end
 
@@ -101,14 +101,14 @@ module Rack
         # response with the session's id.
 
         def commit_session(env, status, headers, body)
-          session = env[Const::RACK_SESSION]
-          options = env[Const::RACK_SESSION_OPTIONS]
+          session = env['rack.session']
+          options = env['rack.session.options']
           session_id = options[:id]
 
           if not session_id = set_session(env, session_id, session, options)
-            env[Const::RACK_ERRORS].puts("Warning! #{self.class.name} failed to save session. Content dropped.")
+            env["rack.errors"].puts("Warning! #{self.class.name} failed to save session. Content dropped.")
           elsif options[:defer] and not options[:renew]
-            env[Const::RACK_ERRORS].puts("Defering cookie for #{session_id}") if $VERBOSE
+            env["rack.errors"].puts("Defering cookie for #{session_id}") if $VERBOSE
           else
             cookie = Hash.new
             cookie[:value] = session_id
diff --git a/lib/rack/session/cookie.rb b/lib/rack/session/cookie.rb
index 9b742a8b..240e6c8d 100644
--- a/lib/rack/session/cookie.rb
+++ b/lib/rack/session/cookie.rb
@@ -13,7 +13,7 @@ module Rack
     #
     # Example:
     #
-    #     use Rack::Session::Cookie, :key => Const::RACK_SESSION,
+    #     use Rack::Session::Cookie, :key => 'rack.session',
     #                                :domain => 'foo.com',
     #                                :path => '/',
     #                                :expire_after => 2592000,
@@ -25,7 +25,7 @@ module Rack
 
       def initialize(app, options={})
         @app = app
-        @key = options[:key] || Const::RACK_SESSION
+        @key = options[:key] || "rack.session"
         @secret = options[:secret]
         @default_options = {:domain => nil,
           :path => "/",
@@ -52,16 +52,16 @@ module Rack
         begin
           session_data = session_data.unpack("m*").first
           session_data = Marshal.load(session_data)
-          env[Const::RACK_SESSION] = session_data
+          env["rack.session"] = session_data
         rescue
-          env[Const::RACK_SESSION] = Hash.new
+          env["rack.session"] = Hash.new
         end
 
-        env[Const::RACK_SESSION_OPTIONS] = @default_options.dup
+        env["rack.session.options"] = @default_options.dup
       end
 
       def commit_session(env, status, headers, body)
-        session_data = Marshal.dump(env[Const::RACK_SESSION])
+        session_data = Marshal.dump(env["rack.session"])
         session_data = [session_data].pack("m*")
 
         if @secret
@@ -69,9 +69,9 @@ module Rack
         end
 
         if session_data.size > (4096 - @key.size)
-          env[Const::RACK_ERRORS].puts("Warning! Rack::Session::Cookie data size exceeds 4K. Content dropped.")
+          env["rack.errors"].puts("Warning! Rack::Session::Cookie data size exceeds 4K. Content dropped.")
         else
-          options = env[Const::RACK_SESSION_OPTIONS]
+          options = env["rack.session.options"]
           cookie = Hash.new
           cookie[:value] = session_data
           cookie[:expires] = Time.now + options[:expire_after] unless options[:expire_after].nil?
diff --git a/lib/rack/session/memcache.rb b/lib/rack/session/memcache.rb
index 220ac937..4a65cbf3 100644
--- a/lib/rack/session/memcache.rb
+++ b/lib/rack/session/memcache.rb
@@ -43,9 +43,9 @@ module Rack
 
       def get_session(env, sid)
         session = @pool.get(sid) if sid
-        @mutex.lock if env[Const::RACK_MULTITHREAD]
+        @mutex.lock if env['rack.multithread']
         unless sid and session
-          env[Const::RACK_ERRORS].puts("Session '#{sid.inspect}' not found, initializing...") if $VERBOSE and not sid.nil?
+          env['rack.errors'].puts("Session '#{sid.inspect}' not found, initializing...") if $VERBOSE and not sid.nil?
           session = {}
           sid = generate_sid
           ret = @pool.add sid, session
@@ -58,14 +58,14 @@ module Rack
         warn $!.inspect
         return [ nil, {} ]
       ensure
-        @mutex.unlock if env[Const::RACK_MULTITHREAD]
+        @mutex.unlock if env['rack.multithread']
       end
 
       def set_session(env, session_id, new_session, options)
         expiry = options[:expire_after]
         expiry = expiry.nil? ? 0 : expiry + 1
 
-        @mutex.lock if env[Const::RACK_MULTITHREAD]
+        @mutex.lock if env['rack.multithread']
         session = @pool.get(session_id) || {}
         if options[:renew] or options[:drop]
           @pool.delete session_id
@@ -82,7 +82,7 @@ module Rack
         warn $!.inspect
         return false
       ensure
-        @mutex.unlock if env[Const::RACK_MULTITHREAD]
+        @mutex.unlock if env['rack.multithread']
       end
 
       private
diff --git a/lib/rack/session/pool.rb b/lib/rack/session/pool.rb
index 872bc601..f6f87408 100644
--- a/lib/rack/session/pool.rb
+++ b/lib/rack/session/pool.rb
@@ -43,9 +43,9 @@ module Rack
 
       def get_session(env, sid)
         session = @pool[sid] if sid
-        @mutex.lock if env[Const::RACK_MULTITHREAD]
+        @mutex.lock if env['rack.multithread']
         unless sid and session
-          env[Const::RACK_ERRORS].puts("Session '#{sid.inspect}' not found, initializing...") if $VERBOSE and not sid.nil?
+          env['rack.errors'].puts("Session '#{sid.inspect}' not found, initializing...") if $VERBOSE and not sid.nil?
           session = {}
           sid = generate_sid
           @pool.store sid, session
@@ -53,11 +53,11 @@ module Rack
         session.instance_variable_set('@old', {}.merge(session))
         return [sid, session]
       ensure
-        @mutex.unlock if env[Const::RACK_MULTITHREAD]
+        @mutex.unlock if env['rack.multithread']
       end
 
       def set_session(env, session_id, new_session, options)
-        @mutex.lock if env[Const::RACK_MULTITHREAD]
+        @mutex.lock if env['rack.multithread']
         session = @pool[session_id]
         if options[:renew] or options[:drop]
           @pool.delete session_id
@@ -73,7 +73,7 @@ module Rack
         warn "#{new_session.inspect} has been lost."
         warn $!.inspect
       ensure
-        @mutex.unlock if env[Const::RACK_MULTITHREAD]
+        @mutex.unlock if env['rack.multithread']
       end
 
       private
diff --git a/lib/rack/showexceptions.rb b/lib/rack/showexceptions.rb
index ba604af0..697bc41f 100644
--- a/lib/rack/showexceptions.rb
+++ b/lib/rack/showexceptions.rb
@@ -25,8 +25,8 @@ module Rack
     rescue StandardError, LoadError, SyntaxError => e
       backtrace = pretty(env, e)
       [500,
-       {Const::CONTENT_TYPE => "text/html",
-        Const::CONTENT_LENGTH => backtrace.join.size.to_s},
+       {"Content-Type" => "text/html",
+        "Content-Length" => backtrace.join.size.to_s},
        backtrace]
     end
 
@@ -58,9 +58,9 @@ module Rack
         end
       }.compact
 
-      env[Const::RACK_ERRORS].puts "#{exception.class}: #{exception.message}"
-      env[Const::RACK_ERRORS].puts exception.backtrace.map { |l| "\t" + l }
-      env[Const::RACK_ERRORS].flush
+      env["rack.errors"].puts "#{exception.class}: #{exception.message}"
+      env["rack.errors"].puts exception.backtrace.map { |l| "\t" + l }
+      env["rack.errors"].flush
 
       [@template.result(binding)]
     end
diff --git a/lib/rack/showstatus.rb b/lib/rack/showstatus.rb
index f2ead40f..28258c7c 100644
--- a/lib/rack/showstatus.rb
+++ b/lib/rack/showstatus.rb
@@ -19,7 +19,7 @@ module Rack
     def call(env)
       status, headers, body = @app.call(env)
       headers = Utils::HeaderHash.new(headers)
-      empty = headers[Const::CONTENT_LENGTH].to_i <= 0
+      empty = headers['Content-Length'].to_i <= 0
 
       # client or server error, or explicit message
       if (status.to_i >= 400 && empty) || env["rack.showstatus.detail"]
@@ -28,7 +28,7 @@ module Rack
         detail = env["rack.showstatus.detail"] || message
         body = @template.result(binding)
         size = Rack::Utils.bytesize(body)
-        [status, headers.merge(Const::CONTENT_TYPE => "text/html", Const::CONTENT_LENGTH => size.to_s), [body]]
+        [status, headers.merge("Content-Type" => "text/html", "Content-Length" => size.to_s), [body]]
       else
         [status, headers, body]
       end
diff --git a/lib/rack/static.rb b/lib/rack/static.rb
index d88d7f14..168e8f83 100644
--- a/lib/rack/static.rb
+++ b/lib/rack/static.rb
@@ -24,7 +24,7 @@ module Rack
     end
 
     def call(env)
-      path = env[Const::ENV_PATH_INFO]
+      path = env["PATH_INFO"]
       can_serve = @urls.any? { |url| path.index(url) == 0 }
 
       if can_serve
diff --git a/lib/rack/urlmap.rb b/lib/rack/urlmap.rb
index 0b80a7e5..fcf6616c 100644
--- a/lib/rack/urlmap.rb
+++ b/lib/rack/urlmap.rb
@@ -34,9 +34,9 @@ module Rack
     end
 
     def call(env)
-      path = env[Const::ENV_PATH_INFO].to_s.squeeze("/")
-      script_name = env[Const::ENV_SCRIPT_NAME]
-      hHost, sName, sPort = env.values_at(Const::ENV_HTTP_HOST, Const::ENV_SERVER_NAME, Const::ENV_SERVER_PORT)
+      path = env["PATH_INFO"].to_s.squeeze("/")
+      script_name = env['SCRIPT_NAME']
+      hHost, sName, sPort = env.values_at('HTTP_HOST','SERVER_NAME','SERVER_PORT')
       @mapping.each { |host, location, app|
         next unless (hHost == host || sName == host \
           || (host.nil? && (hHost == sName || hHost == sName+':'+sPort)))
@@ -45,10 +45,11 @@ module Rack
 
         return app.call(
           env.merge(
-            Const::ENV_SCRIPT_NAME => (script_name + location),
-            Const::ENV_PATH_INFO   => path[location.size..-1]))
+            'SCRIPT_NAME' => (script_name + location),
+            'PATH_INFO'   => path[location.size..-1]))
       }
-      [404, {Const::CONTENT_TYPE => "text/plain"}, ["Not Found: #{path}"]]
+      [404, {"Content-Type" => "text/plain"}, ["Not Found: #{path}"]]
     end
   end
 end
+
diff --git a/lib/rack/utils.rb b/lib/rack/utils.rb
index 1118730a..55f01f3b 100644
--- a/lib/rack/utils.rb
+++ b/lib/rack/utils.rb
@@ -401,7 +401,7 @@ module Rack
       MULTIPART_BOUNDARY = "AaB03x"
 
       def self.parse_multipart(env)
-        unless env[Const::ENV_CONTENT_TYPE] =~
+        unless env['CONTENT_TYPE'] =~
             %r|\Amultipart/.*boundary=\"?([^\";,]+)\"?|n
           nil
         else
@@ -409,8 +409,8 @@ module Rack
 
           params = {}
           buf = ""
-          content_length = env[Const::ENV_CONTENT_LENGTH].to_i
-          input = env[Const::RACK_INPUT]
+          content_length = env['CONTENT_LENGTH'].to_i
+          input = env['rack.input']
           input.rewind
 
           boundary_size = Utils.bytesize(boundary) + EOL.size