pingserver: refactor for separate responsibility

refs #2793

Change-Id: I39e1794fa276d168427eac0164d481109adc6cfe
diff --git a/tools/ping/server/tracer.cpp b/tools/ping/server/tracer.cpp
new file mode 100644
index 0000000..fa4e2c8
--- /dev/null
+++ b/tools/ping/server/tracer.cpp
@@ -0,0 +1,46 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2015,  Arizona Board of Regents.
+ *
+ * This file is part of ndn-tools (Named Data Networking Essential Tools).
+ * See AUTHORS.md for complete list of ndn-tools authors and contributors.
+ *
+ * ndn-tools is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-tools is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * ndn-tools, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @author Eric Newberry <enewberry@email.arizona.edu>
+ */
+
+#include "tracer.hpp"
+
+namespace ndn {
+namespace ping {
+namespace server {
+
+Tracer::Tracer(PingServer& pingServer, const Options& options)
+  : m_options(options)
+{
+  pingServer.afterReceive.connect(bind(&Tracer::onReceive, this, _1));
+}
+
+void
+Tracer::onReceive(const Name& name)
+{
+  if (m_options.shouldPrintTimestamp) {
+    std::cout << time::toIsoString(time::system_clock::now())  << " - ";
+  }
+
+  std::cout << "interest received: seq=" << name.at(-1).toUri() << std::endl;
+}
+
+} // namespace server
+} // namespace ping
+} // namespace ndn
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