TUSCANY-3716 - Adding Tuscany respondeHandler to be able to add HTTP headers that were configured declaratively

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@1021952 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 92 insertions, 6 deletions

diff --git a/sca-java-2.x/trunk/modules/binding-rest-runtime/src/main/java/org/apache/tuscany/sca/binding/rest/provider/TuscanyRESTServlet.java b/sca-java-2.x/trunk/modules/binding-rest-runtime/src/main/java/org/apache/tuscany/sca/binding/rest/provider/TuscanyRESTServlet.java
index f40f69b218..fb9c245f75 100644
--- a/sca-java-2.x/trunk/modules/binding-rest-runtime/src/main/java/org/apache/tuscany/sca/binding/rest/provider/TuscanyRESTServlet.java
+++ b/sca-java-2.x/trunk/modules/binding-rest-runtime/src/main/java/org/apache/tuscany/sca/binding/rest/provider/TuscanyRESTServlet.java
@@ -20,24 +20,43 @@
 package org.apache.tuscany.sca.binding.rest.provider;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Calendar;
+import java.util.Collections;
+import java.util.Date;
 import java.util.Enumeration;
+import java.util.GregorianCalendar;
+import java.util.List;
+import java.util.Properties;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import javax.ws.rs.HttpMethod;
+import javax.ws.rs.core.Application;
 import javax.ws.rs.core.MediaType;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.SAXParserFactory;
-import javax.xml.transform.TransformerFactory;
-import javax.xml.validation.SchemaFactory;
 
+import org.apache.tuscany.sca.assembly.Binding;
+import org.apache.tuscany.sca.binding.rest.RESTBinding;
+import org.apache.tuscany.sca.common.http.HTTPCacheContext;
+import org.apache.tuscany.sca.common.http.HTTPHeader;
 import org.apache.tuscany.sca.core.ExtensionPointRegistry;
 import org.apache.tuscany.sca.extensibility.ClassLoaderContext;
 import org.apache.wink.common.internal.registry.ProvidersRegistry;
 import org.apache.wink.common.internal.registry.metadata.MethodMetadata;
+import org.apache.wink.server.handlers.HandlersChain;
+import org.apache.wink.server.handlers.HandlersFactory;
+import org.apache.wink.server.handlers.MessageContext;
+import org.apache.wink.server.handlers.RequestHandler;
+import org.apache.wink.server.handlers.ResponseHandler;
 import org.apache.wink.server.internal.DeploymentConfiguration;
 import org.apache.wink.server.internal.RequestProcessor;
+import org.apache.wink.server.internal.handlers.CheckLocationHeaderHandler;
 import org.apache.wink.server.internal.registry.ResourceRecord;
 import org.apache.wink.server.internal.servlet.RestServlet;
 
@@ -45,14 +64,18 @@ import org.apache.wink.server.internal.servlet.RestServlet;
  *
  */
 public class TuscanyRESTServlet extends RestServlet {
+    private static final Logger logger = Logger.getLogger(TuscanyRESTServlet.class.getName());
+    
     private static final long serialVersionUID = 89997233133964915L;
     private ExtensionPointRegistry registry;
+    private RESTBinding binding;
     private Class<?> resourceClass;
     private boolean fixed;
 
-    public TuscanyRESTServlet(ExtensionPointRegistry registry, Class<?> resourceClass) {
+    public TuscanyRESTServlet(ExtensionPointRegistry registry, Binding binding, Class<?> resourceClass) {
         super();
         this.registry = registry;
+        this.binding = (RESTBinding) binding;
         this.resourceClass = resourceClass;
     }
     
@@ -70,7 +93,16 @@ public class TuscanyRESTServlet extends RestServlet {
             }
         }
     }
+    
+    /**
+     * Create Tuscany own DeploymentConfiguration in order to be able to 
+     * add ResponseHandler to the Wink HandlerChain
+     */
+    public DeploymentConfiguration createDeploymentConfiguration() throws ClassNotFoundException, InstantiationException, IllegalAccessException { 
+        return new TuscanyDeploymentConfiguration();
+    }
 
+    @SuppressWarnings({"unchecked", "rawtypes"})
     @Override
     public DeploymentConfiguration getDeploymentConfiguration() throws ClassNotFoundException, InstantiationException,
         IllegalAccessException, IOException {
@@ -117,7 +149,7 @@ public class TuscanyRESTServlet extends RestServlet {
         ProvidersRegistry providers = config.getProvidersRegistry();
         providers.addProvider(new DataBindingJAXRSReader(registry), 0.001, true);
         providers.addProvider(new DataBindingJAXRSWriter(registry), 0.001, true);
-
+        
         return config;
     }
 
@@ -162,5 +194,59 @@ public class TuscanyRESTServlet extends RestServlet {
         }
         return processor;
     }
+    
+    /**
+     * TuscanyDeploymentConfiguration
+     * 
+     * Required to inject TuscanyResponseHandler to the HandlerChain
+     */
+    class TuscanyDeploymentConfiguration extends DeploymentConfiguration {
+        
+        @Override
+        protected List<ResponseHandler> initResponseUserHandlers() {
+            List<ResponseHandler> list = super.initResponseUserHandlers();
+            list.add(new TuscanyResponseHandler());
+            return list;
+        }
+    }
+    
+    /**
+     * TuscanyResponseHandler
+     * 
+     * Required to support declartive HTTP Headers
+     */
+    class TuscanyResponseHandler implements ResponseHandler {
+        public void handleResponse(MessageContext context, HandlersChain chain) throws Throwable {
+            
+            // assert response is not committed
+            final HttpServletResponse httpResponse = context.getAttribute(HttpServletResponse.class);
+            if (httpResponse.isCommitted()) {
+                logger.log(Level.FINE, "The response is already committed. Nothing to do.");
+                return;
+            }
+            
+            //process declarative headers
+            for(HTTPHeader header : binding.getHttpHeaders()) {                
+                //treat special headers that need to be calculated
+                if(header.getName().equalsIgnoreCase("Expires")) {
+                    GregorianCalendar calendar = new GregorianCalendar();
+                    calendar.setTime(new Date());
+
+                    calendar.add(Calendar.HOUR, Integer.parseInt(header.getValue()));
+
+                    httpResponse.setHeader("Expires", HTTPCacheContext.RFC822DateFormat.format( calendar.getTime() ));
+                } else {
+                    //default behaviour to pass the header value to HTTP response
+                    httpResponse.setHeader(header.getName(), header.getValue());
+                }
+            }     
+
+            chain.doChain(context);
+        }
+
+        public void init(Properties props) {
+
+        }        
+    }
 
 }