Add filter adding HTTP headers (#4824)

Author: Radoslav Petrov

frameworks/Java/grizzly/src/main/java/org/glassfish/grizzly/bm/HeadersFilter.java

@@ -0,0 +1,44 @@
+package org.glassfish.grizzly.bm;
+
+import java.io.IOException;
+
+import org.glassfish.grizzly.filterchain.FilterChainContext;
+import org.glassfish.grizzly.filterchain.NextAction;
+import org.glassfish.grizzly.http.HttpBaseFilter;
+import org.glassfish.grizzly.http.HttpContent;
+import org.glassfish.grizzly.http.HttpPacket;
+import org.glassfish.grizzly.http.HttpRequestPacket;
+import org.glassfish.grizzly.http.HttpResponsePacket;
+import org.glassfish.grizzly.http.util.FastHttpDateFormat;
+import org.glassfish.grizzly.http.util.Header;
+
+/**
+ * Must be added just before the HttpServerFilter i.e. second to last in the filter chain.
+ * 
+ * @author zloster
+ *
+ */
+public class HeadersFilter extends HttpBaseFilter {
+
+	@Override
+	protected void bind(HttpRequestPacket request, HttpResponsePacket response) {
+		// This is never called. I don't know why.
+		super.bind(request, response);
+	}
+
+	@Override
+	public NextAction handleRead(FilterChainContext ctx) throws IOException {
+		// Taken from HttpServerFilter
+		final Object message = ctx.getMessage();
+		if (HttpPacket.isHttp(message)) {
+			// Otherwise cast message to a HttpContent
+			final HttpContent httpContent = (HttpContent) message;
+			final HttpRequestPacket request = (HttpRequestPacket) httpContent.getHttpHeader();
+			final HttpResponsePacket response = request.getResponse();
+			response.setHeader(Header.Server, Server.SERVER_VERSION);
+			response.setHeader(Header.Date, FastHttpDateFormat.getCurrentDate());
+		}
+		return super.handleRead(ctx);
+	}
+
+}

frameworks/Java/grizzly/src/main/java/org/glassfish/grizzly/bm/JsonHttpHandler.java

@@ -1,14 +1,12 @@
 package org.glassfish.grizzly.bm;
 
-import com.fasterxml.jackson.databind.*;
-
 import org.glassfish.grizzly.http.server.HttpHandler;
 import org.glassfish.grizzly.http.server.Request;
 import org.glassfish.grizzly.http.server.RequestExecutorProvider;
 import org.glassfish.grizzly.http.server.Response;
 import org.glassfish.grizzly.http.util.ContentType;
-import org.glassfish.grizzly.http.util.FastHttpDateFormat;
-import org.glassfish.grizzly.http.util.Header;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
 
 /**
  * JSON test
@@ -27,9 +25,6 @@ public static class HelloMessage {
 	@Override
 	public void service(final Request request, final Response response) throws Exception {
 		response.setContentType(CONTENT_TYPE);
-		response.setHeader(Header.Server, Server.SERVER_VERSION);
-		response.setHeader(Header.Date, FastHttpDateFormat.getCurrentDate());
-
 		// Write JSON encoded message to the response.
 		MAPPER.writeValue(response.getOutputStream(), new HelloMessage());
 	}

frameworks/Java/grizzly/src/main/java/org/glassfish/grizzly/bm/PlainText2HttpHandler.java

@@ -5,8 +5,6 @@
 import org.glassfish.grizzly.http.server.RequestExecutorProvider;
 import org.glassfish.grizzly.http.server.Response;
 import org.glassfish.grizzly.http.util.ContentType;
-import org.glassfish.grizzly.http.util.FastHttpDateFormat;
-import org.glassfish.grizzly.http.util.Header;
 import org.glassfish.grizzly.utils.Charsets;
 
 /**
@@ -22,9 +20,6 @@ public class PlainText2HttpHandler extends HttpHandler {
 	@Override
 	public void service(final Request request, final Response response) throws Exception {
 		response.setContentType(CONTENT_TYPE);
-		response.setHeader(Header.Server, Server.SERVER_VERSION);
-		response.setHeader(Header.Date, FastHttpDateFormat.getCurrentDate());
-
 		response.getOutputStream().write(HELLO_WORLD_BYTES);
 	}
 

frameworks/Java/grizzly/src/main/java/org/glassfish/grizzly/bm/PlainTextHttpHandler.java

@@ -5,8 +5,6 @@
 import org.glassfish.grizzly.http.server.RequestExecutorProvider;
 import org.glassfish.grizzly.http.server.Response;
 import org.glassfish.grizzly.http.util.ContentType;
-import org.glassfish.grizzly.http.util.FastHttpDateFormat;
-import org.glassfish.grizzly.http.util.Header;
 
 /**
  * Plaintext test case
@@ -18,8 +16,6 @@ public class PlainTextHttpHandler extends HttpHandler {
 	@Override
 	public void service(final Request request, final Response response) throws Exception {
 		response.setContentType(CONTENT_TYPE);
-		response.setHeader(Header.Server, Server.SERVER_VERSION);
-		response.setHeader(Header.Date, FastHttpDateFormat.getCurrentDate());
 		response.getWriter().write("Hello, World!");
 	}
 

frameworks/Java/grizzly/src/main/java/org/glassfish/grizzly/bm/Server.java

@@ -59,6 +59,9 @@ public static void main(String[] args) throws Exception {
 
 		try {
 			httpServer.start();
+			// This can't be done before the call to start(). Also note the
+			// positions
+			httpServer.getListener("http-listener").getFilterChain().add(3, new HeadersFilter());
 			synchronized (Server.class) {
 				Server.class.wait();
 			}