When handling OPTION calls ignore both 'Date' and 'Allow' headers to …

src/main/java/org/jruby/rack/servlet/ResponseCapture.java

@@ -12,8 +12,11 @@
 import java.io.PrintWriter;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
 
 import javax.servlet.ServletOutputStream;
 import javax.servlet.http.HttpServletRequest;
@@ -24,6 +27,13 @@
  * Response wrapper passed to filter chain.
  */
 public class ResponseCapture extends HttpServletResponseWrapper {
+    /**
+     * In case of OPTION calls we check what headers are set by the servlet to decide if a request is
+     * already handled. Some container implementation of DefaultServlet already set 'Allow' and/or 'Date' fields which
+     * we need to ignore when working with this approach
+     */
+    private static final Set<String> HEADERS_NOT_CONSIDERED_HANDLED_FOR_OPTIONS_CALL
+            = new HashSet<String>(Arrays.asList("Allow", "Date"));
 
     private static final String STREAM = "stream";
     private static final String WRITER = "writer";
@@ -230,9 +240,10 @@ public boolean isHandled(final HttpServletRequest request) {
                     // not to happen but there's all kind of beasts out there
                     return false;
                 }
+                // if any other headers occur beside 'Allow' and 'Date' we consider this request handled.
                 for ( final String headerName : headerNames ) {
-                    if ( ! "Allow".equals( headerName ) ) {
-                        return handled = true; // not just Allow header - consider handled
+                    if ( !HEADERS_NOT_CONSIDERED_HANDLED_FOR_OPTIONS_CALL.contains(headerName) ) {
+                        return handled = true;
                     }
                 }
                 return false; // OPTIONS with only Allow header set - unhandled

src/spec/ruby/rack/servlet/response_capture_spec.rb

@@ -65,6 +65,16 @@
     expect( response_capture.isHandled(servlet_request) ).to be false
   end
 
+  it "is not considered handled when only Allow or Date header is added with OPTIONS" do
+    servlet_request.method = 'OPTIONS'
+
+    # NOTE: Jetty sets both Date and Allow in DefaultServlet#doOptions
+    response_capture.addHeader "Allow", "GET, POST, OPTIONS"
+    response_capture.addHeader "Date", Time.now.httpdate
+
+    expect( response_capture.isHandled(servlet_request) ).to be false
+  end
+
   it "is considered handled when more than Allow header is added with OPTIONS" do
     pending "need Servlet API 3.0" unless servlet_30?
 
@@ -100,4 +110,4 @@ def servlet_30?
     Java::JavaClass.for_name('javax.servlet.AsyncContext') rescue nil
   end
 
-end
+end