face: ProtocolFactory registry

refs #3904

Change-Id: Ic7c8b3d6138b7c27d4189a2e15cc646055ad1294
diff --git a/daemon/face/unix-stream-factory.cpp b/daemon/face/unix-stream-factory.cpp
index b800b7c..19a39dc 100644
--- a/daemon/face/unix-stream-factory.cpp
+++ b/daemon/face/unix-stream-factory.cpp
@@ -32,6 +32,15 @@
 namespace face {
 
 NFD_LOG_INIT("UnixStreamFactory");
+NFD_REGISTER_PROTOCOL_FACTORY(UnixStreamFactory);
+
+const std::string&
+UnixStreamFactory::getId()
+{
+  static std::string id("unix");
+  return id;
+}
+
 
 void
 UnixStreamFactory::processConfig(OptionalConfigSection configSection,