From 9462fc579988a0218b1c9c85d76f53ff029c0a12 Mon Sep 17 00:00:00 2001
From: Adam Wegrzynek <awegrzyn@users.noreply.github.com>
Date: Fri, 4 May 2018 15:07:35 +0200
Subject: [PATCH] Add noop backend (#53)

---
 CMakeLists.txt            |  1 +
 src/Backends/Noop.h       | 51 +++++++++++++++++++++++++++++++++++++++
 src/MonitoringFactory.cxx |  6 +++++
 test/testNoop.cxx         | 20 +++++++++++++++
 4 files changed, 78 insertions(+)
 create mode 100644 src/Backends/Noop.h
 create mode 100644 test/testNoop.cxx

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6fbf07fbd..6b32000de 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -145,6 +145,7 @@ set(TEST_SRCS
         test/testProcessDetails.cxx
         test/testProcessMonitor.cxx
 	test/testInfluxDb.cxx
+        test/testNoop.cxx
         )
 if(APMON_FOUND)
   list(APPEND TEST_SRCS test/testApMon.cxx)
diff --git a/src/Backends/Noop.h b/src/Backends/Noop.h
new file mode 100644
index 000000000..3e0cf50ca
--- /dev/null
+++ b/src/Backends/Noop.h
@@ -0,0 +1,51 @@
+///
+/// \file Noop.h
+/// \author Adam Wegrzynek <adam.wegrzynek@cern.ch>
+///
+
+#ifndef ALICEO2_MONITORING_BACKENDS_NOOP_H
+#define ALICEO2_MONITORING_BACKENDS_NOOP_H
+
+#include "Monitoring/Backend.h"
+
+namespace o2
+{
+/// ALICE O2 Monitoring system
+namespace monitoring
+{
+/// Monitoring backends
+namespace backends
+{
+
+/// \brief No-op backend
+///
+/// \author Adam Wegrzynek <adam.wegrzynek@cern.ch>
+class Noop final : public Backend
+{
+  public:
+    /// Constructs backend
+    Noop() = default;
+
+    /// Default destructor
+    ~Noop() = default;
+
+    /// \@param metrics  vector of metrics
+    void send(std::vector<Metric>&& /*metrics*/) final {}
+
+    /// \param metric           reference to metric object:
+    void send(const Metric& /*metric*/) final {}
+
+    /// \param measurement     measurement name
+    /// \param metrics  list of metrics
+    void sendMultiple(std::string /*measurement*/, std::vector<Metric>&& /*metrics*/) final {}
+
+    /// \param name             tag name
+    /// \param value            tag value that is concatenated to entity string
+    void addGlobalTag(std::string /*name*/, std::string /*value*/) final {}
+};
+
+} // namespace backends
+} // namespace monitoring
+} // namespace o2
+
+#endif // ALICEO2_MONITORING_BACKENDS_NOOP_H
diff --git a/src/MonitoringFactory.cxx b/src/MonitoringFactory.cxx
index 56059c053..02cc1a872 100644
--- a/src/MonitoringFactory.cxx
+++ b/src/MonitoringFactory.cxx
@@ -12,6 +12,7 @@
 
 #include "Backends/InfoLoggerBackend.h"
 #include "Backends/Flume.h"
+#include "Backends/Noop.h"
 
 #ifdef _WITH_APPMON
 #include "Backends/ApMonBackend.h"
@@ -55,6 +56,10 @@ std::unique_ptr<Backend> getApMon(http::url /*uri*/) {
 }
 #endif
 
+std::unique_ptr<Backend> getNoop(http::url /*uri*/) {
+  return std::make_unique<backends::Noop>();
+}
+
 std::unique_ptr<Backend> getFlume(http::url uri) {
   return std::make_unique<backends::Flume>(uri.host, uri.port);
 }
@@ -66,6 +71,7 @@ std::unique_ptr<Backend> MonitoringFactory::GetBackend(std::string& url) {
     {"influxdb-http", getInfluxDb},
     {"apmon", getApMon},
     {"flume", getFlume},
+    {"no-op", getNoop}
   };
 
   http::url parsedUrl = http::ParseHttpUrl(url);
diff --git a/test/testNoop.cxx b/test/testNoop.cxx
new file mode 100644
index 000000000..f03c0d6b5
--- /dev/null
+++ b/test/testNoop.cxx
@@ -0,0 +1,20 @@
+#define BOOST_TEST_MODULE Test Monitoring Flume
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+
+#include "../src/Backends/Noop.h"
+
+namespace o2 {
+namespace monitoring {
+namespace Test {
+
+BOOST_AUTO_TEST_CASE(noopSendMetric)
+{
+  o2::monitoring::backends::Noop noopBackend{};
+  o2::monitoring::Metric metric{10, "myCrazyMetric"};
+  noopBackend.send(metric);
+}
+
+} // namespace Test
+} // namespace monitoring
+} // namespace o2