[#1025] Allow to add extra headers to the websocket handshake response

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerHandshaker.java

@@ -19,6 +19,7 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.FullHttpRequest;
+import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.util.internal.StringUtil;
 
 import java.util.Collections;
@@ -113,10 +114,7 @@ public abstract class WebSocketServerHandshaker {
      *            HTTP Request
      */
     public ChannelFuture handshake(Channel channel, FullHttpRequest req) {
-        if (channel == null) {
+        return handshake(channel, req, null, channel.newPromise());
-            throw new NullPointerException("channel");
-        }
-        return handshake(channel, req, channel.newPromise());
     }
 
     /**
@@ -126,10 +124,13 @@ public abstract class WebSocketServerHandshaker {
      *            Channel
      * @param req
      *            HTTP Request
+     * @param responseHeaders
+     *            Extra headers to add to the handshake response or {@code null} if no extra headers should be added
      * @param promise
      *            the {@link ChannelPromise} to be notified when the opening handshake is done
      */
-    public abstract ChannelFuture handshake(Channel channel, FullHttpRequest req, ChannelPromise promise);
+    public abstract ChannelFuture handshake(Channel channel, FullHttpRequest req,
+                                            HttpHeaders responseHeaders, ChannelPromise promise);
 
     /**
      * Performs the closing handshake

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerHandshaker00.java

@@ -25,6 +25,7 @@ import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
 import io.netty.handler.codec.http.FullHttpResponse;
+import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.handler.codec.http.HttpHeaders.Names;
 import io.netty.handler.codec.http.HttpHeaders.Values;
 import io.netty.handler.codec.http.HttpObjectAggregator;
@@ -112,14 +113,9 @@ public class WebSocketServerHandshaker00 extends WebSocketServerHandshaker {
      *
      * 8jKS'y:G*Co,Wxa-
      * </pre>
-     *
-     * @param channel
-     *            Channel
-     * @param req
-     *            HTTP request
      */
     @Override
-    public ChannelFuture handshake(Channel channel, FullHttpRequest req, ChannelPromise promise) {
+    public ChannelFuture handshake(Channel channel, FullHttpRequest req, HttpHeaders headers, ChannelPromise promise) {
 
         if (logger.isDebugEnabled()) {
             logger.debug(String.format("Channel %s WS Version 00 server handshake", channel.id()));
@@ -137,6 +133,10 @@ public class WebSocketServerHandshaker00 extends WebSocketServerHandshaker {
         // Create the WebSocket handshake response.
         FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, new HttpResponseStatus(101,
                 isHixie76 ? "WebSocket Protocol Handshake" : "Web Socket Protocol Handshake"));
+        if (headers != null) {
+            res.headers().add(headers);
+        }
+
         res.headers().add(Names.UPGRADE, WEBSOCKET);
         res.headers().add(CONNECTION, Values.UPGRADE);
 

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerHandshaker07.java

@@ -23,6 +23,7 @@ import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
 import io.netty.handler.codec.http.FullHttpResponse;
+import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.handler.codec.http.HttpHeaders.Names;
 import io.netty.handler.codec.http.HttpObjectAggregator;
 import io.netty.handler.codec.http.HttpRequestDecoder;
@@ -102,14 +103,9 @@ public class WebSocketServerHandshaker07 extends WebSocketServerHandshaker {
      * Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
      * Sec-WebSocket-Protocol: chat
      * </pre>
-     *
-     * @param channel
-     *            Channel
-     * @param req
-     *            HTTP request
      */
     @Override
-    public ChannelFuture handshake(Channel channel, FullHttpRequest req, ChannelPromise promise) {
+    public ChannelFuture handshake(Channel channel, FullHttpRequest req, HttpHeaders headers, ChannelPromise promise) {
 
         if (logger.isDebugEnabled()) {
             logger.debug(String.format("Channel %s WS Version 7 server handshake", channel.id()));
@@ -118,6 +114,10 @@ public class WebSocketServerHandshaker07 extends WebSocketServerHandshaker {
         FullHttpResponse res =
                 new DefaultFullHttpResponse(HTTP_1_1, HttpResponseStatus.SWITCHING_PROTOCOLS);
 
+        if (headers != null) {
+            res.headers().add(headers);
+        }
+
         String key = req.headers().get(Names.SEC_WEBSOCKET_KEY);
         if (key == null) {
             throw new WebSocketHandshakeException("not a WebSocket request: missing key");

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerHandshaker08.java

@@ -22,6 +22,7 @@ import io.netty.channel.ChannelPipeline;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.DefaultHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
+import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.handler.codec.http.HttpHeaders.Names;
 import io.netty.handler.codec.http.HttpObjectAggregator;
 import io.netty.handler.codec.http.HttpRequestDecoder;
@@ -103,14 +104,9 @@ public class WebSocketServerHandshaker08 extends WebSocketServerHandshaker {
      * Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
      * Sec-WebSocket-Protocol: chat
      * </pre>
-     *
-     * @param channel
-     *            Channel
-     * @param req
-     *            HTTP request
      */
     @Override
-    public ChannelFuture handshake(Channel channel, FullHttpRequest req, ChannelPromise promise) {
+    public ChannelFuture handshake(Channel channel, FullHttpRequest req, HttpHeaders headers, ChannelPromise promise) {
 
         if (logger.isDebugEnabled()) {
             logger.debug(String.format("Channel %s WS Version 8 server handshake", channel.id()));
@@ -118,6 +114,10 @@ public class WebSocketServerHandshaker08 extends WebSocketServerHandshaker {
 
         HttpResponse res = new DefaultHttpResponse(HTTP_1_1, HttpResponseStatus.SWITCHING_PROTOCOLS);
 
+        if (headers != null) {
+            res.headers().add(headers);
+        }
+
         String key = req.headers().get(Names.SEC_WEBSOCKET_KEY);
         if (key == null) {
             throw new WebSocketHandshakeException("not a WebSocket request: missing key");

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerHandshaker13.java

@@ -22,6 +22,7 @@ import io.netty.channel.ChannelPipeline;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.DefaultHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
+import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.handler.codec.http.HttpHeaders.Names;
 import io.netty.handler.codec.http.HttpObjectAggregator;
 import io.netty.handler.codec.http.HttpRequestDecoder;
@@ -102,20 +103,18 @@ public class WebSocketServerHandshaker13 extends WebSocketServerHandshaker {
      * Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
      * Sec-WebSocket-Protocol: chat
      * </pre>
-     *
-     * @param channel
-     *            Channel
-     * @param req
-     *            HTTP request
      */
     @Override
-    public ChannelFuture handshake(Channel channel, FullHttpRequest req, ChannelPromise promise) {
+    public ChannelFuture handshake(Channel channel, FullHttpRequest req, HttpHeaders headers, ChannelPromise promise) {
 
         if (logger.isDebugEnabled()) {
             logger.debug(String.format("Channel %s WS Version 13 server handshake", channel.id()));
         }
 
         HttpResponse res = new DefaultHttpResponse(HTTP_1_1, HttpResponseStatus.SWITCHING_PROTOCOLS);
+        if (headers != null) {
+            res.headers().add(headers);
+        }
 
         String key = req.headers().get(Names.SEC_WEBSOCKET_KEY);
         if (key == null) {