PubSub: Modify WriterGroup message settings

 - Change PublisherId to static number from random
   number generation
 - Enable the following in writerGroup settings
     - PublisherId
     - WriterGroupId in GroupHeader
     - PayloadHeader

Change-Id: I7f3865a0d1b8bffcb4d228f44409d790cba7afcb

examples/pubsub/tutorial_pubsub_publish.c

@@ -46,7 +46,9 @@ addPubSubConnection(UA_Server *server, UA_String *transportProfile,
     connectionConfig.enabled = UA_TRUE;
     UA_Variant_setScalar(&connectionConfig.address, networkAddressUrl,
                          &UA_TYPES[UA_TYPES_NETWORKADDRESSURLDATATYPE]);
-    connectionConfig.publisherId.numeric = UA_UInt32_random();
+    /* Changed to static publisherId from random generation to identify
+     * the publisher on Subscriber side */
+    connectionConfig.publisherId.numeric = 2234;
     UA_Server_addPubSubConnection(server, &connectionConfig, &connectionIdent);
 }
 
@@ -106,11 +108,23 @@ addWriterGroup(UA_Server *server) {
     writerGroupConfig.enabled = UA_FALSE;
     writerGroupConfig.writerGroupId = 100;
     writerGroupConfig.encodingMimeType = UA_PUBSUB_ENCODING_UADP;
+    writerGroupConfig.messageSettings.encoding             = UA_EXTENSIONOBJECT_DECODED;
+    writerGroupConfig.messageSettings.content.decoded.type = &UA_TYPES[UA_TYPES_UADPWRITERGROUPMESSAGEDATATYPE];
     /* The configuration flags for the messages are encapsulated inside the
      * message- and transport settings extension objects. These extension
      * objects are defined by the standard. e.g.
      * UadpWriterGroupMessageDataType */
+    UA_UadpWriterGroupMessageDataType *writerGroupMessage  = UA_UadpWriterGroupMessageDataType_new();
+    /* Change message settings of writerGroup to send PublisherId,
+     * WriterGroupId in GroupHeader and DataSetWriterId in PayloadHeader
+     * of NetworkMessage */
+    writerGroupMessage->networkMessageContentMask          = (UA_UadpNetworkMessageContentMask)(UA_UADPNETWORKMESSAGECONTENTMASK_PUBLISHERID |
+                                                              (UA_UadpNetworkMessageContentMask)UA_UADPNETWORKMESSAGECONTENTMASK_GROUPHEADER |
+                                                              (UA_UadpNetworkMessageContentMask)UA_UADPNETWORKMESSAGECONTENTMASK_WRITERGROUPID |
+                                                              (UA_UadpNetworkMessageContentMask)UA_UADPNETWORKMESSAGECONTENTMASK_PAYLOADHEADER);
+    writerGroupConfig.messageSettings.content.decoded.data = writerGroupMessage;
     UA_Server_addWriterGroup(server, connectionIdent, &writerGroupConfig, &writerGroupIdent);
+    UA_UadpWriterGroupMessageDataType_delete(writerGroupMessage);
 }
 
 /**