From b7c615c335ba4f522cc43e8ad1cc74b6dbec6ca7 Mon Sep 17 00:00:00 2001
From: Pieter van de Bruggen <pvande@gmail.com>
Date: Mon, 28 Jan 2013 17:31:08 -0800
Subject: [PATCH] Exposing Accept header parameters.

---
 lib/sinatra/base.rb  | 49 +++++++++++++++++++++++++++++++++-----------
 test/request_test.rb | 15 ++++++++++++++
 2 files changed, 52 insertions(+), 12 deletions(-)

diff --git a/lib/sinatra/base.rb b/lib/sinatra/base.rb
index a8dcb5a1..65c7c69b 100644
--- a/lib/sinatra/base.rb
+++ b/lib/sinatra/base.rb
@@ -16,16 +16,15 @@ module Sinatra
   # The request object. See Rack::Request for more info:
   # http://rack.rubyforge.org/doc/classes/Rack/Request.html
   class Request < Rack::Request
-    HEADER_PARAM = /;[\d\w.]+=(?:[\d\w.]+|"(?:[^"\\]|\\.)*")?/
-    HEADER_VALUE_WITH_PARAMS = /(?:(?:\w+|\*)\/(?:\w+|\*))(?:#{HEADER_PARAM})*/
+    HEADER_PARAM = /\s*[\d\w._]+=(?:[\d\w._]+|"(?:[^"\\]|\\.)*")?\s*/
+    HEADER_VALUE_WITH_PARAMS = /(?:(?:\w+|\*)\/(?:\w+|\*))\s*(?:;#{HEADER_PARAM})*/
 
     # Returns an array of acceptable media types for the response
     def accept
-      @env['sinatra.accept_entries'] ||= begin
+      @env['sinatra.accept'] ||= begin
         entries = @env['HTTP_ACCEPT'].to_s.scan(HEADER_VALUE_WITH_PARAMS)
-        entries.map { |e| accept_entry(e) }.sort_by(&:last)
+        entries.map { |e| AcceptEntry.new(e) }.sort
       end
-      @env['sinatra.accept'] ||= @env['sinatra.accept_entries'].map(&:first)
     end
 
     def preferred_type(*types)
@@ -54,12 +53,37 @@ module Sinatra
 
     private
 
-    def accept_entry(entry)
-      type = entry.delete(' ').split(';').first
-      options = entry.scan(HEADER_PARAM).map { |s| s[1..-1] }
-      quality = 0 # we sort smallest first
-      options.delete_if { |e| quality = 1 - e[2..-1].to_f if e.start_with? 'q=' }
-      [type, options, [quality, type.count('*'), 1 - options.size]]
+    class AcceptEntry
+      attr_accessor :params
+
+      def initialize(entry)
+        params = entry.scan(HEADER_PARAM).map do |s|
+          key, value = s.strip.split('=', 2)
+          value = value[1..-2].gsub(/\\(.)/, '\1') if value.start_with?('"')
+          [key, value]
+        end
+
+        @type = entry[/[^;]+/].delete(' ')
+        @params = Hash[params]
+        @q = @params.delete('q') { "1.0" }.to_f
+      end
+
+      def <=>(other)
+        other.priority <=> self.priority
+      end
+
+      def priority
+        # We sort in descending order; better matches should be higher.
+        [ @q, -@type.count('*'), @params.size ]
+      end
+
+      def [](param)
+        @params[param]
+      end
+
+      def to_str
+        @type
+      end
     end
   end
 
@@ -1293,7 +1317,8 @@ module Sinatra
           if type = response['Content-Type']
             types.include? type or types.include? type[/^[^;]+/]
           elsif type = request.preferred_type(types)
-            content_type(type)
+            params = (type.respond_to?(:params) ? type.params : {})
+            content_type(type, params)
             true
           else
             false
diff --git a/test/request_test.rb b/test/request_test.rb
index 13abad4c..fa28bd8b 100644
--- a/test/request_test.rb
+++ b/test/request_test.rb
@@ -42,4 +42,19 @@ class RequestTest < Test::Unit::TestCase
     dumped = Marshal.dump(request.params)
     assert_equal 'bar', Marshal.load(dumped)['foo']
   end
+
+  it "exposes the preferred type's parameters" do
+    request = Sinatra::Request.new(
+      'HTTP_ACCEPT' => 'image/jpeg; compress=0.25'
+    )
+    assert_equal({ 'compress' => '0.25' }, request.preferred_type.params)
+  end
+
+  it "properly decodes MIME type parameters" do
+    request = Sinatra::Request.new(
+      'HTTP_ACCEPT' => 'image/jpeg;unquoted=0.25;quoted="0.25";chartest="\";,\x"'
+    )
+    expected = { 'unquoted' => '0.25', 'quoted' => '0.25', 'chartest' => '";,x' }
+    assert_equal(expected, request.preferred_type.params)
+  end
 end