snake unsubscription fixes

ws/ixcobra/IXCobraConnection.cpp

@@ -192,7 +192,7 @@ namespace ix
                     {
                         if (!handleUnsubscriptionResponse(data))
                         {
-                            invokeErrorCallback("Error processing subscribe response", msg->str);
+                            invokeErrorCallback("Error processing unsubscribe response", msg->str);
                         }
                     }
                     else if (action == "rtm/unsubscribe/error")

ws/snake/IXSnakeProtocol.cpp

@@ -287,12 +287,18 @@ namespace snake
         const AppConfig& appConfig,
         const nlohmann::json& pdu)
     {
+        // extract subscription_id
+        auto body = pdu["body"];
+        auto subscriptionId = body["subscription_id"];
+
         state->redisClient().stop();
 
         nlohmann::json response = {
             {"action", "rtm/unsubscribe/ok"},
             {"id", pdu.value("id", 1)},
-            {"body", {}}
+            {"body", {
+                {"subscription_id", subscriptionId}
+            }}
         };
         ws->sendText(response.dump());
     }