Added new metrics for warnings.

- *__flow__warnings__type_count: the number of unique warning types
- *__flow__warnings__count:<TOOL>-<ID>

Signed-off-by: Jaehyun Kim <jhkim@precisioninno.com>

Author: jhkim-pii

src/utl/include/utl/Logger.h

@@ -279,6 +279,7 @@ class Logger
            const Args&... args)
   {
     assert(id >= 0 && id <= max_message_id);
+    message_levels_[tool][id].store(level, std::memory_order_relaxed);
     auto& counter = message_counters_[tool][id];
     auto count = counter++;
     if (count < max_message_print) {
@@ -319,6 +320,9 @@ class Logger
 
   void flushMetrics();
   void finalizeMetrics();
+  // Add new metric for each non-zero warning. It also counts the number of
+  // unique warning types.
+  void addWarningMetrics();
 
   void setRedirectSink(std::ostream& sink_stream, bool keep_sinks = false);
   void restoreFromRedirect();
@@ -359,6 +363,9 @@ class Logger
   // from multiple threads without locks.
   using MessageCounter = std::array<std::atomic_int16_t, max_message_id + 1>;
   std::array<MessageCounter, ToolId::SIZE> message_counters_;
+  using MessageLevel
+      = std::array<std::atomic<spdlog::level::level_enum>, max_message_id + 1>;
+  std::array<MessageLevel, ToolId::SIZE> message_levels_;
   std::array<DebugGroups, ToolId::SIZE> debug_group_level_;
   bool debug_on_{false};
   std::atomic_int warning_count_{0};

src/utl/src/Logger.cpp

@@ -58,6 +58,12 @@ Logger::Logger(const char* log_filename, const char* metrics_filename)
     }
   }
 
+  for (auto& levels : message_levels_) {
+    for (auto& level : levels) {
+      level.store(spdlog::level::off, std::memory_order_relaxed);
+    }
+  }
+
   prometheus_registry_ = std::make_shared<PrometheusRegistry>();
 }
 
@@ -178,11 +184,33 @@ void Logger::flushMetrics()
   }
 }
 
+void Logger::addWarningMetrics()
+{
+  // Add metrics for non-zero warnings
+  int warning_type_cnt = 0;
+  for (int i = 0; i < ToolId::SIZE; ++i) {
+    for (int j = 0; j <= max_message_id; ++j) {
+      if (message_counters_[i][j] > 0
+          && message_levels_[i][j] == spdlog::level::warn) {
+        warning_type_cnt++;
+        log_metric(
+            fmt::format("flow__warnings__count:{}-{}", tool_names_[i], j),
+            std::to_string(message_counters_[i][j]));
+      }
+    }
+  }
+
+  // Add a metric to report the number of unique warning types
+  log_metric("flow__warnings__type_count", std::to_string(warning_type_cnt));
+}
+
 void Logger::finalizeMetrics()
 {
   log_metric("flow__warnings__count", std::to_string(warning_count_));
   log_metric("flow__errors__count", std::to_string(error_count_));
 
+  addWarningMetrics();
+
   for (MetricsPolicy policy : metrics_policies_) {
     policy.applyPolicy(metrics_entries_);
   }