3 files changed, 14 insertions, 8 deletions
diff --git a/actionpack/lib/action_dispatch/http/cache.rb b/actionpack/lib/action_dispatch/http/cache.rb
index cc1cb3f0f0..be87343b20 100644
--- a/actionpack/lib/action_dispatch/http/cache.rb
+++ b/actionpack/lib/action_dispatch/http/cache.rb
@@ -8,13 +8,13 @@ module ActionDispatch
         HTTP_IF_NONE_MATCH     = 'HTTP_IF_NONE_MATCH'.freeze
 
         def if_modified_since
-          if since = env[HTTP_IF_MODIFIED_SINCE]
+          if since = get_header(HTTP_IF_MODIFIED_SINCE)
             Time.rfc2822(since) rescue nil
           end
         end
 
         def if_none_match
-          env[HTTP_IF_NONE_MATCH]
+          get_header HTTP_IF_NONE_MATCH
         end
 
         def if_none_match_etags
diff --git a/actionpack/lib/action_dispatch/http/request.rb b/actionpack/lib/action_dispatch/http/request.rb
index 4748a54550..a3c6f015d9 100644
--- a/actionpack/lib/action_dispatch/http/request.rb
+++ b/actionpack/lib/action_dispatch/http/request.rb
@@ -35,7 +35,8 @@ module ActionDispatch
         HTTP_ACCEPT_LANGUAGE HTTP_CACHE_CONTROL HTTP_FROM
         HTTP_NEGOTIATE HTTP_PRAGMA HTTP_CLIENT_IP
         HTTP_X_FORWARDED_FOR HTTP_VERSION
-        HTTP_X_REQUEST_ID
+        HTTP_X_REQUEST_ID HTTP_X_FORWARDED_HOST
+        SERVER_ADDR
         ].freeze
 
     ENV_METHODS.each do |env|
@@ -323,7 +324,9 @@ module ActionDispatch
 
     # Override Rack's GET method to support indifferent access
     def GET
-      @env["action_dispatch.request.query_parameters"] ||= normalize_encode_params(super || {})
+      get_header("action_dispatch.request.query_parameters") do |k|
+        set_header k, normalize_encode_params(super || {})
+      end
     rescue Rack::Utils::ParameterTypeError, Rack::Utils::InvalidParameterError => e
       raise ActionController::BadRequest.new(:query, e)
     end
@@ -331,7 +334,9 @@ module ActionDispatch
 
     # Override Rack's POST method to support indifferent access
     def POST
-      @env["action_dispatch.request.request_parameters"] ||= normalize_encode_params(super || {})
+      get_header("action_dispatch.request.request_parameters") do
+        self.request_parameters = normalize_encode_params(super || {})
+      end
     rescue Rack::Utils::ParameterTypeError, Rack::Utils::InvalidParameterError => e
       raise ActionController::BadRequest.new(:request, e)
     end
@@ -352,6 +357,7 @@ module ActionDispatch
     end
 
     def request_parameters=(params)
+      raise if params.nil?
       set_header("action_dispatch.request.request_parameters".freeze, params)
     end
 
diff --git a/actionpack/lib/action_dispatch/http/url.rb b/actionpack/lib/action_dispatch/http/url.rb
index 6fcf49030b..e413954066 100644
--- a/actionpack/lib/action_dispatch/http/url.rb
+++ b/actionpack/lib/action_dispatch/http/url.rb
@@ -229,10 +229,10 @@ module ActionDispatch
       #   req = Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.raw_host_with_port # => "example.com:8080"
       def raw_host_with_port
-        if forwarded = env["HTTP_X_FORWARDED_HOST"].presence
+        if forwarded = x_forwarded_host.presence
           forwarded.split(/,\s?/).last
         else
-          env['HTTP_HOST'] || "#{env['SERVER_NAME'] || env['SERVER_ADDR']}:#{env['SERVER_PORT']}"
+          get_header('HTTP_HOST') || "#{server_name || server_addr}:#{get_header('SERVER_PORT')}"
         end
       end
 
@@ -348,7 +348,7 @@ module ActionDispatch
       end
 
       def server_port
-        @env['SERVER_PORT'].to_i
+        get_header('SERVER_PORT').to_i
       end
 
       # Returns the \domain part of a \host, such as "rubyonrails.org" in "www.rubyonrails.org". You can specify