send_file now copes with 'Range: bytes=100-400,500-600' headers

Signed-off-by: Konstantin Haase <konstantin.mailinglists@googlemail.com>

lib/sinatra/base.rb

@@ -161,8 +161,18 @@ module Sinatra
       elsif opts[:disposition] == 'inline'
         response['Content-Disposition'] = 'inline'
       end
-
-      halt StaticFile.open(path, 'rb')
+      sf = StaticFile.open(path, 'rb')
+      if (env['HTTP_RANGE'] =~ /^bytes=(\d+-\d+(?:,\d+-\d+)*)$/)
+        sf.ranges = $1.split(',').collect{|range| range.split('-').collect{|n| n.to_i}}
+        sf.ranges.each do |range|
+          halt 416 if range[1] < range[0]
+        end
+        response['Content-Range'] = "bytes #{$1}/#{response['Content-Length']}"
+        response['Content-Length'] = sf.ranges.dup.inject(0){|total,range| total + range[1] - range[0] + 1 }.to_s
+        halt 206, sf
+      else
+        halt sf
+      end
     rescue Errno::ENOENT
       not_found
     end
@@ -171,10 +181,25 @@ module Sinatra
     # generated iteratively in 8K chunks.
     class StaticFile < ::File #:nodoc:
       alias_method :to_path, :path
+      
+      attr_accessor :ranges
+      
       def each
-        rewind
-        while buf = read(8192)
-          yield buf
+        if @ranges
+          @ranges.each do |range|
+            self.pos = range[0]
+            length = range[1] - range[0] + 1
+            while buf = read([8192,length.abs].min)
+              yield buf
+              length -= buf.length
+              break if (length -= 8192) + 8192 <= 0
+            end
+          end
+        else
+          rewind
+          while buf = read(8192)
+            yield buf
+          end
         end
       end
     end

test/static_test.rb

@@ -90,4 +90,29 @@ class StaticTest < Test::Unit::TestCase
     get "/../#{File.basename(__FILE__)}"
     assert not_found?
   end
+
+  it 'deals correctly with incompletable range requests' do
+    request = Rack::MockRequest.new(@app)
+    response = request.get("/#{File.basename(__FILE__)}", 'HTTP_RANGE' => "bytes=45-40")
+    
+    assert_equal 416,response.status, "Ranges with final position < initial position should give HTTP/1.1 416 Requested Range Not Satisfiable"
+  end
+
+  it 'accepts and returns byte ranges correctly' do
+    [[[42,88]],[[1,5],[6,85]]].each do |ranges|
+      request = Rack::MockRequest.new(@app)
+      response = request.get("/#{File.basename(__FILE__)}", 'HTTP_RANGE' => "bytes=#{ranges.map{|r| r.join('-')}.join(',')}")
+      
+      file = File.read(__FILE__)
+      should_be = ''
+      ranges.each do |range|
+        should_be += file[range[0]..range[1]]
+      end
+        
+      assert_equal 206,response.status, "Should be HTTP/1.1 206 Partial content"
+      assert_equal should_be, response.body
+      assert_equal should_be.length.to_s, response['Content-Length'], "Length given was not the same as Content-Length reported"
+      assert_equal "bytes #{ranges.map{|r| r.join('-')}.join(',')}/#{File.size(__FILE__)}", response['Content-Range'],"Content-Range header was not correct"
+    end
+  end
 end