Merge branch 'main' into exemplar

examples/common/metrics_foo_library/foo_library.cc

@@ -39,13 +39,16 @@ class MeasurementFetcher
     if (nostd::holds_alternative<
             nostd::shared_ptr<opentelemetry::metrics::ObserverResultT<double>>>(observer_result))
     {
-      double val = (rand() % 700) + 1.1;
+      double random_incr = (rand() % 5) + 1.1;
+      value_ += random_incr;
       nostd::get<nostd::shared_ptr<opentelemetry::metrics::ObserverResultT<double>>>(
           observer_result)
-          ->Observe(val /*, labelkv */);
+          ->Observe(value_ /*, labelkv */);
     }
   }
+  static double value_;
 };
+double MeasurementFetcher::value_ = 0.0;
 }  // namespace
 
 void foo_library::counter_example(const std::string &name)

examples/metrics_simple/metrics_ostream.cc

@@ -62,7 +62,7 @@ void initMetrics(const std::string &name)
   std::unique_ptr<metric_sdk::MeterSelector> observable_meter_selector{
       new metric_sdk::MeterSelector(name, version, schema)};
   std::unique_ptr<metric_sdk::View> observable_sum_view{
-      new metric_sdk::View{name, "description", metric_sdk::AggregationType::kSum}};
+      new metric_sdk::View{name, "test_description", metric_sdk::AggregationType::kSum}};
   p->AddView(std::move(observable_instrument_selector), std::move(observable_meter_selector),
              std::move(observable_sum_view));
 

exporters/ostream/src/metric_exporter.cc

@@ -205,16 +205,7 @@ void OStreamMetricExporter::printPointData(const opentelemetry::sdk::metrics::Po
     }
 
     sout_ << "\n  buckets     : ";
-    if (nostd::holds_alternative<std::list<double>>(histogram_point_data.boundaries_))
-    {
-      auto &double_boundaries = nostd::get<std::list<double>>(histogram_point_data.boundaries_);
-      printVec(sout_, double_boundaries);
-    }
-    else if (nostd::holds_alternative<std::list<long>>(histogram_point_data.boundaries_))
-    {
-      auto &long_boundaries = nostd::get<std::list<long>>(histogram_point_data.boundaries_);
-      printVec(sout_, long_boundaries);
-    }
+    printVec(sout_, histogram_point_data.boundaries_);
 
     sout_ << "\n  counts     : ";
     printVec(sout_, histogram_point_data.counts_);

exporters/ostream/test/ostream_metric_test.cc

@@ -105,7 +105,7 @@ TEST(OStreamMetricsExporter, ExportHistogramPointData)
   histogram_point_data.min_        = 1.8;
   histogram_point_data.max_        = 12.0;
   metric_sdk::HistogramPointData histogram_point_data2{};
-  histogram_point_data2.boundaries_ = std::list<long>{10, 20, 30};
+  histogram_point_data2.boundaries_ = std::list<double>{10.0, 20.0, 30.0};
   histogram_point_data2.count_      = 3;
   histogram_point_data2.counts_     = {200, 300, 400, 500};
   histogram_point_data2.sum_        = 900l;

exporters/otlp/src/otlp_metric_utils.cc

@@ -126,21 +126,10 @@ void OtlpMetricUtils::ConvertHistogramMetric(
       }
     }
     // buckets
-    if ((nostd::holds_alternative<std::list<double>>(histogram_data.boundaries_)))
-    {
-      auto boundaries = nostd::get<std::list<double>>(histogram_data.boundaries_);
-      for (auto bound : boundaries)
-      {
-        proto_histogram_point_data->add_explicit_bounds(bound);
-      }
-    }
-    else
+
+    for (auto bound : histogram_data.boundaries_)
     {
-      auto boundaries = nostd::get<std::list<long>>(histogram_data.boundaries_);
-      for (auto bound : boundaries)
-      {
-        proto_histogram_point_data->add_explicit_bounds(bound);
-      }
+      proto_histogram_point_data->add_explicit_bounds(bound);
     }
     // bucket counts
     for (auto bucket_value : histogram_data.counts_)

exporters/otlp/test/otlp_http_metric_exporter_test.cc

@@ -482,14 +482,14 @@ class OtlpHttpMetricExporterTestPeer : public ::testing::Test
     auto exporter = GetExporter(std::unique_ptr<OtlpHttpClient>{mock_otlp_http_client});
 
     opentelemetry::sdk::metrics::HistogramPointData histogram_point_data{};
-    histogram_point_data.boundaries_ = std::list<double>{10.1, 20.2, 30.2};
+    histogram_point_data.boundaries_ = {10.1, 20.2, 30.2};
     histogram_point_data.count_      = 3;
     histogram_point_data.counts_     = {200, 300, 400, 500};
     histogram_point_data.sum_        = 900.5;
     histogram_point_data.min_        = 1.8;
     histogram_point_data.max_        = 19.0;
     opentelemetry::sdk::metrics::HistogramPointData histogram_point_data2{};
-    histogram_point_data2.boundaries_ = std::list<long>{10, 20, 30};
+    histogram_point_data2.boundaries_ = {10.0, 20.0, 30.0};
     histogram_point_data2.count_      = 3;
     histogram_point_data2.counts_     = {200, 300, 400, 500};
     histogram_point_data2.sum_        = 900l;
@@ -619,12 +619,12 @@ class OtlpHttpMetricExporterTestPeer : public ::testing::Test
         "library_name", "1.5.0");
 
     opentelemetry::sdk::metrics::HistogramPointData histogram_point_data{};
-    histogram_point_data.boundaries_ = std::list<double>{10.1, 20.2, 30.2};
+    histogram_point_data.boundaries_ = {10.1, 20.2, 30.2};
     histogram_point_data.count_      = 3;
     histogram_point_data.counts_     = {200, 300, 400, 500};
     histogram_point_data.sum_        = 900.5;
     opentelemetry::sdk::metrics::HistogramPointData histogram_point_data2{};
-    histogram_point_data2.boundaries_ = std::list<long>{10, 20, 30};
+    histogram_point_data2.boundaries_ = {10.0, 20.0, 30.0};
     histogram_point_data2.count_      = 3;
     histogram_point_data2.counts_     = {200, 300, 400, 500};
     histogram_point_data2.sum_        = 900l;

exporters/prometheus/include/opentelemetry/exporters/prometheus/exporter_utils.h

@@ -68,7 +68,7 @@ class PrometheusExporterUtils
    */
   template <typename T>
   static void SetData(std::vector<T> values,
-                      const opentelemetry::sdk::metrics::ListType &boundaries,
+                      const std::list<double> &boundaries,
                       const std::vector<uint64_t> &counts,
                       const opentelemetry::sdk::metrics::PointAttributes &labels,
                       std::chrono::nanoseconds time,
@@ -103,9 +103,9 @@ class PrometheusExporterUtils
   /**
    * Handle Histogram
    */
-  template <typename T, typename U>
+  template <typename T>
   static void SetValue(std::vector<T> values,
-                       const std::list<U> &boundaries,
+                       const std::list<double> &boundaries,
                        const std::vector<uint64_t> &counts,
                        ::prometheus::ClientMetric *metric);
 };

exporters/prometheus/src/exporter_utils.cc

@@ -197,7 +197,7 @@ void PrometheusExporterUtils::SetData(std::vector<T> values,
  */
 template <typename T>
 void PrometheusExporterUtils::SetData(std::vector<T> values,
-                                      const opentelemetry::sdk::metrics::ListType &boundaries,
+                                      const std::list<double> &boundaries,
                                       const std::vector<uint64_t> &counts,
                                       const metric_sdk::PointAttributes &labels,
                                       std::chrono::nanoseconds time,
@@ -206,14 +206,7 @@ void PrometheusExporterUtils::SetData(std::vector<T> values,
   metric_family->metric.emplace_back();
   prometheus_client::ClientMetric &metric = metric_family->metric.back();
   SetMetricBasic(metric, time, labels);
-  if (nostd::holds_alternative<std::list<long>>(boundaries))
-  {
-    SetValue(values, nostd::get<std::list<long>>(boundaries), counts, &metric);
-  }
-  else
-  {
-    SetValue(values, nostd::get<std::list<double>>(boundaries), counts, &metric);
-  }
+  SetValue(values, boundaries, counts, &metric);
 }
 
 /**
@@ -321,9 +314,9 @@ void PrometheusExporterUtils::SetValue(std::vector<T> values,
 /**
  * Handle Histogram
  */
-template <typename T, typename U>
+template <typename T>
 void PrometheusExporterUtils::SetValue(std::vector<T> values,
-                                       const std::list<U> &boundaries,
+                                       const std::list<double> &boundaries,
                                        const std::vector<uint64_t> &counts,
                                        prometheus_client::ClientMetric *metric)
 {

exporters/prometheus/test/prometheus_test_helper.h

@@ -46,12 +46,12 @@ inline metric_sdk::ResourceMetrics CreateSumPointData()
 inline metric_sdk::ResourceMetrics CreateHistogramPointData()
 {
   metric_sdk::HistogramPointData histogram_point_data{};
-  histogram_point_data.boundaries_ = std::list<double>{10.1, 20.2, 30.2};
+  histogram_point_data.boundaries_ = {10.1, 20.2, 30.2};
   histogram_point_data.count_      = 3;
   histogram_point_data.counts_     = {200, 300, 400, 500};
   histogram_point_data.sum_        = 900.5;
   metric_sdk::HistogramPointData histogram_point_data2{};
-  histogram_point_data2.boundaries_ = std::list<long>{10, 20, 30};
+  histogram_point_data2.boundaries_ = {10.0, 20.0, 30.0};
   histogram_point_data2.count_      = 3;
   histogram_point_data2.counts_     = {200, 300, 400, 500};
   histogram_point_data2.sum_        = 900l;

sdk/include/opentelemetry/sdk/logs/batch_log_processor.h

@@ -64,7 +64,7 @@ class BatchLogProcessor : public LogProcessor
    * @param record the log record
    */
 
-  void OnReceive(std::unique_ptr<Recordable> &&record) noexcept override;
+  void OnEmit(std::unique_ptr<Recordable> &&record) noexcept override;
 
   /**
    * Export all log records that have not been exported yet.

sdk/include/opentelemetry/sdk/logs/multi_log_processor.h

@@ -36,10 +36,10 @@ class MultiLogProcessor : public LogProcessor
   std::unique_ptr<Recordable> MakeRecordable() noexcept override;
 
   /**
-   * OnReceive is called by the SDK once a log record has been successfully created.
+   * OnEmit is called by the SDK once a log record has been successfully created.
    * @param record the log record
    */
-  void OnReceive(std::unique_ptr<Recordable> &&record) noexcept override;
+  void OnEmit(std::unique_ptr<Recordable> &&record) noexcept override;
 
   /**
    * Exports all log records that have not yet been exported to the configured Exporter.

sdk/include/opentelemetry/sdk/logs/processor.h

@@ -32,10 +32,10 @@ class LogProcessor
   virtual std::unique_ptr<Recordable> MakeRecordable() noexcept = 0;
 
   /**
-   * OnReceive is called by the SDK once a log record has been successfully created.
+   * OnEmit is called by the SDK once a log record has been successfully created.
    * @param record the log record
    */
-  virtual void OnReceive(std::unique_ptr<Recordable> &&record) noexcept = 0;
+  virtual void OnEmit(std::unique_ptr<Recordable> &&record) noexcept = 0;
 
   /**
    * Exports all log records that have not yet been exported to the configured Exporter.

sdk/include/opentelemetry/sdk/logs/simple_log_processor.h

@@ -33,7 +33,7 @@ class SimpleLogProcessor : public LogProcessor
 
   std::unique_ptr<Recordable> MakeRecordable() noexcept override;
 
-  void OnReceive(std::unique_ptr<Recordable> &&record) noexcept override;
+  void OnEmit(std::unique_ptr<Recordable> &&record) noexcept override;
 
   bool ForceFlush(
       std::chrono::microseconds timeout = std::chrono::microseconds::max()) noexcept override;

sdk/include/opentelemetry/sdk/metrics/aggregation/aggregation_config.h

@@ -20,7 +20,7 @@ template <typename T>
 class HistogramAggregationConfig : public AggregationConfig
 {
 public:
-  std::list<T> boundaries_;
+  std::list<double> boundaries_;
   bool record_min_max_ = true;
 };
 }  // namespace metrics

sdk/include/opentelemetry/sdk/metrics/data/point_data.h

@@ -17,7 +17,6 @@ namespace metrics
 {
 
 using ValueType = nostd::variant<long, double>;
-using ListType  = nostd::variant<std::list<long>, std::list<double>>;
 
 // TODO: remove ctors and initializers from below classes when GCC<5 stops shipping on Ubuntu
 
@@ -55,8 +54,8 @@ class HistogramPointData
   HistogramPointData &operator=(HistogramPointData &&) = default;
   HistogramPointData(const HistogramPointData &)       = default;
   HistogramPointData()                                 = default;
-
-  ListType boundaries_          = {};
+  HistogramPointData(std::list<double> &boundaries) : boundaries_(boundaries) {}
+  std::list<double> boundaries_ = {};
   ValueType sum_                = {};
   ValueType min_                = {};
   ValueType max_                = {};

sdk/include/opentelemetry/sdk/metrics/state/async_metric_storage.h

@@ -43,7 +43,9 @@ class AsyncMetricStorage : public MetricStorage, public AsyncWritableMetricStora
   void Record(const std::unordered_map<MetricAttributes, T, AttributeHashGenerator> &measurements,
               opentelemetry::common::SystemTimestamp /* observation_time */) noexcept
   {
-    // process the read measurements - aggregate and store in hashmap
+    // Async counter always record monotonically increasing values, and the
+    // exporter/reader can request either for delta or cumulative value.
+    // So we convert the async counter value to delta before passing it to temporal storage.
     std::lock_guard<opentelemetry::common::SpinLockMutex> guard(hashmap_lock_);
     for (auto &measurement : measurements)
     {
@@ -53,13 +55,14 @@ class AsyncMetricStorage : public MetricStorage, public AsyncWritableMetricStora
       if (prev)
       {
         auto delta = prev->Diff(*aggr);
-        cumulative_hash_map_->Set(measurement.first,
-                                  DefaultAggregation::CloneAggregation(
-                                      aggregation_type_, instrument_descriptor_, *delta));
+        // store received value in cumulative map, and the diff in delta map (to pass it to temporal
+        // storage)
+        cumulative_hash_map_->Set(measurement.first, std::move(aggr));
         delta_hash_map_->Set(measurement.first, std::move(delta));
       }
       else
       {
+        // store received value in cumulative and delta map.
         cumulative_hash_map_->Set(
             measurement.first,
             DefaultAggregation::CloneAggregation(aggregation_type_, instrument_descriptor_, *aggr));

sdk/src/logs/batch_log_processor.cc

@@ -53,7 +53,7 @@ std::unique_ptr<Recordable> BatchLogProcessor::MakeRecordable() noexcept
   return exporter_->MakeRecordable();
 }
 
-void BatchLogProcessor::OnReceive(std::unique_ptr<Recordable> &&record) noexcept
+void BatchLogProcessor::OnEmit(std::unique_ptr<Recordable> &&record) noexcept
 {
   if (synchronization_data_->is_shutdown.load() == true)
   {

sdk/src/logs/logger.cc

@@ -111,7 +111,7 @@ void Logger::Log(opentelemetry::logs::Severity severity,
   }
 
   // Send the log record to the processor
-  processor.OnReceive(std::move(recordable));
+  processor.OnEmit(std::move(recordable));
 }
 
 const opentelemetry::sdk::instrumentationscope::InstrumentationScope &

sdk/src/logs/multi_log_processor.cc

@@ -48,7 +48,7 @@ std::unique_ptr<Recordable> MultiLogProcessor::MakeRecordable() noexcept
   return recordable;
 }
 
-void MultiLogProcessor::OnReceive(std::unique_ptr<Recordable> &&record) noexcept
+void MultiLogProcessor::OnEmit(std::unique_ptr<Recordable> &&record) noexcept
 {
   if (!record)
   {
@@ -61,7 +61,7 @@ void MultiLogProcessor::OnReceive(std::unique_ptr<Recordable> &&record) noexcept
     auto recordable = multi_recordable->ReleaseRecordable(*processor);
     if (recordable)
     {
-      processor->OnReceive(std::move(recordable));
+      processor->OnEmit(std::move(recordable));
     }
   }
 }

sdk/src/logs/simple_log_processor.cc

@@ -29,7 +29,7 @@ std::unique_ptr<Recordable> SimpleLogProcessor::MakeRecordable() noexcept
  * Batches the log record it receives in a batch of 1 and immediately sends it
  * to the configured exporter
  */
-void SimpleLogProcessor::OnReceive(std::unique_ptr<Recordable> &&record) noexcept
+void SimpleLogProcessor::OnEmit(std::unique_ptr<Recordable> &&record) noexcept
 {
   nostd::span<std::unique_ptr<Recordable>> batch(&record, 1);
   // Get lock to ensure Export() is never called concurrently

sdk/src/metrics/aggregation/histogram_aggregation.cc

@@ -24,14 +24,15 @@ LongHistogramAggregation::LongHistogramAggregation(
   }
   else
   {
-    point_data_.boundaries_ = std::list<long>{0l, 5l, 10l, 25l, 50l, 75l, 100l, 250l, 500l, 1000l};
+    point_data_.boundaries_ = {0.0,   5.0,   10.0,   25.0,   50.0,   75.0,   100.0,  250.0,
+                               500.0, 750.0, 1000.0, 2500.0, 5000.0, 7500.0, 10000.0};
   }
+
   if (aggregation_config)
   {
     record_min_max_ = aggregation_config->record_min_max_;
   }
-  point_data_.counts_ =
-      std::vector<uint64_t>(nostd::get<std::list<long>>(point_data_.boundaries_).size() + 1, 0);
+  point_data_.counts_         = std::vector<uint64_t>(point_data_.boundaries_.size() + 1, 0);
   point_data_.sum_            = 0l;
   point_data_.count_          = 0;
   point_data_.record_min_max_ = record_min_max_;
@@ -59,8 +60,7 @@ void LongHistogramAggregation::Aggregate(long value,
     point_data_.max_ = std::max(nostd::get<long>(point_data_.max_), value);
   }
   size_t index = 0;
-  for (auto it = nostd::get<std::list<long>>(point_data_.boundaries_).begin();
-       it != nostd::get<std::list<long>>(point_data_.boundaries_).end(); ++it)
+  for (auto it = point_data_.boundaries_.begin(); it != point_data_.boundaries_.end(); ++it)
   {
     if (value < *it)
     {
@@ -114,8 +114,7 @@ DoubleHistogramAggregation::DoubleHistogramAggregation(
   {
     record_min_max_ = aggregation_config->record_min_max_;
   }
-  point_data_.counts_ =
-      std::vector<uint64_t>(nostd::get<std::list<double>>(point_data_.boundaries_).size() + 1, 0);
+  point_data_.counts_         = std::vector<uint64_t>(point_data_.boundaries_.size() + 1, 0);
   point_data_.sum_            = 0.0;
   point_data_.count_          = 0;
   point_data_.record_min_max_ = record_min_max_;
@@ -143,8 +142,7 @@ void DoubleHistogramAggregation::Aggregate(double value,
     point_data_.max_ = std::max(nostd::get<double>(point_data_.max_), value);
   }
   size_t index = 0;
-  for (auto it = nostd::get<std::list<double>>(point_data_.boundaries_).begin();
-       it != nostd::get<std::list<double>>(point_data_.boundaries_).end(); ++it)
+  for (auto it = point_data_.boundaries_.begin(); it != point_data_.boundaries_.end(); ++it)
   {
     if (value < *it)
     {

sdk/src/metrics/meter.cc

@@ -293,7 +293,6 @@ std::unique_ptr<AsyncWritableMetricStorage> Meter::RegisterAsyncMetricStorage(
 std::vector<MetricData> Meter::Collect(CollectorHandle *collector,
                                        opentelemetry::common::SystemTimestamp collect_ts) noexcept
 {
-
   observable_registry_->Observe(collect_ts);
   std::vector<MetricData> metric_data_list;
   auto ctx = meter_context_.lock();

sdk/src/metrics/state/temporal_metric_storage.cc

@@ -34,6 +34,7 @@ bool TemporalMetricStorage::buildMetrics(CollectorHandle *collector,
   opentelemetry::common::SystemTimestamp last_collection_ts = sdk_start_ts;
   AggregationTemporality aggregation_temporarily =
       collector->GetAggregationTemporality(instrument_descriptor_.type_);
+
   if (delta_metrics->Size())
   {
     for (auto &col : collectors)