Implement statistics collection: (#2056)

1. Add `-s` CLI key to get statistics file path
2. Implement `StatisticsWriter` singleton to manage handle to this file

tests/time_tests/common/cli.h

@@ -21,6 +21,9 @@ static const char target_device_message[] = "Required. Specify a target device t
 "Use \"-d MULTI:<comma-separated_devices_list>\" format to specify MULTI plugin. " \
 "The application looks for a suitable plugin for the specified device.";
 
+/// @brief message for statistics path argument
+static const char statistics_path_message[] = "Required. Path to a file to write statistics.";
+
 /// @brief Define flag for showing help message <br>
 DEFINE_bool(h, false, help_message);
 
@@ -35,6 +38,10 @@ DEFINE_string(m, "", model_message);
 /// It is a required parameter
 DEFINE_string(d, "", target_device_message);
 
+/// @brief Define parameter for set path to a file to write statistics <br>
+/// It is a required parameter
+DEFINE_string(s, "", statistics_path_message);
+
 /**
 * @brief This function show a help message
 */
@@ -46,4 +53,5 @@ static void showUsage() {
     std::cout << "    -h, --help                " << help_message << std::endl;
     std::cout << "    -m \"<path>\"               " << model_message << std::endl;
     std::cout << "    -d \"<device>\"             " << target_device_message << std::endl;
+    std::cout << "    -s \"<path>\"               " << statistics_path_message << std::endl;
 }

tests/time_tests/common/main.cpp

@@ -3,6 +3,7 @@
 //
 
 #include "cli.h"
+#include "statistics_writer.h"
 #include "../ftti_pipeline/ftti_pipeline.h"
 
 #include <iostream>
@@ -23,6 +24,9 @@ bool parseAndCheckCommandLine(int argc, char **argv) {
     if (FLAGS_d.empty())
         throw std::logic_error("Device is required but not set. Please set -d option.");
 
+    if (FLAGS_s.empty())
+        throw std::logic_error("Statistics file path is required but not set. Please set -s option.");
+
     return true;
 }
 
@@ -43,5 +47,6 @@ int main(int argc, char **argv) {
     if (!parseAndCheckCommandLine(argc, argv))
         return -1;
 
+    StatisticsWriter::Instance().setFile(FLAGS_s);
     return _runPipeline();
 }

tests/time_tests/common/statistics_writer.h

@@ -0,0 +1,55 @@
+// Copyright (C) 2020 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#pragma once
+
+#include <string>
+#include <sstream>
+#include <fstream>
+#include <cstdio>
+
+
+/**
+ * @brief Class response for writing provided statistics
+ *
+ * Object of the class is writing provided statistics to a specified
+ * file in YAML format.
+ */
+class StatisticsWriter {
+private:
+    std::ofstream statistics_file;
+
+    StatisticsWriter() = default;
+    StatisticsWriter(const StatisticsWriter&) = delete;
+    StatisticsWriter& operator=(const StatisticsWriter&) = delete;
+public:
+    /**
+     * @brief Creates StatisticsWriter singleton object
+     */
+    static StatisticsWriter& Instance(){
+        static StatisticsWriter writer;
+        return writer;
+    }
+
+    /**
+     * @brief Specifies, opens and validates statistics path for writing
+     */
+    void setFile(const std::string &statistics_path) {
+        statistics_file.open(statistics_path);
+        if (!statistics_file.good()) {
+            std::stringstream err;
+            err << "Statistic file \"" << statistics_path << "\" can't be used for writing";
+            throw std::runtime_error(err.str());
+        }
+    }
+
+    /**
+     * @brief Writes provided statistics in YAML format.
+     */
+    void write(const std::pair<std::string, float> &record) {
+        if (!statistics_file)
+            throw std::runtime_error("Statistic file path isn't set");
+        statistics_file << record.first << ": " << record.second << "\n";
+    }
+};

tests/time_tests/common/timer.h

@@ -5,11 +5,12 @@
 #pragma once
 
 #include <string>
-#include <map>
 #include <chrono>
 #include <fstream>
 #include <memory>
 
+#include "statistics_writer.h"
+
 using time_point = std::chrono::high_resolution_clock::time_point;
 
 /**
@@ -38,7 +39,7 @@ public:
     ~Timer(){
         float duration = std::chrono::duration_cast<std::chrono::microseconds>(
                 std::chrono::high_resolution_clock::now() - start_time).count();
-        std::cout << name << ":" << duration << "\n"; // TODO: replace with writer
+        StatisticsWriter::Instance().write({name, duration});
     }
 };