only add cross origin header if the request is coming from a browser

modules/elasticsearch/src/main/java/org/elasticsearch/http/HttpHelper.java

@@ -0,0 +1,38 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search licenses this
+ * file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.http;
+
+import org.elasticsearch.common.Nullable;
+
+/**
+ */
+public class HttpHelper {
+
+    public static boolean isBrowser(@Nullable String userAgent) {
+        if (userAgent == null) {
+            return false;
+        }
+        // chrome, safari, firefox, ie
+        if (userAgent.startsWith("Mozilla")) {
+            return true;
+        }
+        return false;
+    }
+}

modules/elasticsearch/src/main/java/org/elasticsearch/http/netty/NettyHttpChannel.java

@@ -36,6 +36,7 @@ import org.elasticsearch.common.netty.handler.codec.http.HttpVersion;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.http.HttpChannel;
 import org.elasticsearch.http.HttpException;
+import org.elasticsearch.http.HttpHelper;
 import org.elasticsearch.rest.RestResponse;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.rest.XContentRestResponse;
@@ -77,6 +78,7 @@ public class NettyHttpChannel implements HttpChannel {
         } else {
             resp = new DefaultHttpResponse(HttpVersion.HTTP_1_1, status);
         }
+        if (HttpHelper.isBrowser(request.getHeader(HttpHeaders.Names.USER_AGENT))) {
             // add support for cross origin
             resp.addHeader("Access-Control-Allow-Origin", "*");
             if (request.getMethod() == HttpMethod.OPTIONS) {
@@ -85,6 +87,7 @@ public class NettyHttpChannel implements HttpChannel {
                 resp.addHeader("Access-Control-Allow-Methods", "PUT, DELETE");
                 resp.addHeader("Access-Control-Allow-Headers", "X-Requested-With");
             }
+        }
 
         // Convert the response content to a ChannelBuffer.
         ChannelFutureListener releaseContentListener = null;