[EXPORTER] Add option to disable Prometheus otel_scope_name and otel_…

…scope_version attributes (#2451)

exporters/prometheus/include/opentelemetry/exporters/prometheus/collector.h

@@ -31,7 +31,9 @@ class PrometheusCollector : public prometheus_client::Collectable
    * This constructor initializes the collection for metrics to export
    * in this class with default capacity
    */
-  explicit PrometheusCollector(sdk::metrics::MetricReader *reader, bool populate_target_info);
+  explicit PrometheusCollector(sdk::metrics::MetricReader *reader,
+                               bool populate_target_info,
+                               bool populate_otel_scope);
 
   /**
    * Collects all metrics data from metricsToCollect collection.
@@ -43,6 +45,7 @@ class PrometheusCollector : public prometheus_client::Collectable
 private:
   sdk::metrics::MetricReader *reader_;
   bool populate_target_info_;
+  bool populate_otel_scope_;
 
   /*
    * Lock when operating the metricsToCollect collection

exporters/prometheus/include/opentelemetry/exporters/prometheus/exporter_options.h

@@ -25,6 +25,9 @@ struct PrometheusExporterOptions
 
   // Populating target_info
   bool populate_target_info = true;
+
+  // Populating otel_scope_name/otel_scope_labels attributes
+  bool populate_otel_scope = true;
 };
 
 }  // namespace metrics

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

@@ -28,11 +28,14 @@ class PrometheusExporterUtils
    *
    * @param records a collection of metrics in OpenTelemetry
    * @param populate_target_info whether to populate target_info
+   * @param populate_otel_scope whether to populate otel_scope_name and otel_scope_version
+   * attributes
    * @return a collection of translated metrics that is acceptable by Prometheus
    */
   static std::vector<::prometheus::MetricFamily> TranslateToPrometheus(
       const sdk::metrics::ResourceMetrics &data,
-      bool populate_target_info = true);
+      bool populate_target_info = true,
+      bool populate_otel_scope  = true);
 
 private:
   /**

exporters/prometheus/src/collector.cc

@@ -18,8 +18,11 @@ namespace metrics
  * in this class with default capacity
  */
 PrometheusCollector::PrometheusCollector(sdk::metrics::MetricReader *reader,
-                                         bool populate_target_info)
-    : reader_(reader), populate_target_info_(populate_target_info)
+                                         bool populate_target_info,
+                                         bool populate_otel_scope)
+    : reader_(reader),
+      populate_target_info_(populate_target_info),
+      populate_otel_scope_(populate_otel_scope)
 {}
 
 /**
@@ -41,8 +44,8 @@ std::vector<prometheus_client::MetricFamily> PrometheusCollector::Collect() cons
   std::vector<prometheus_client::MetricFamily> result;
 
   reader_->Collect([&result, this](sdk::metrics::ResourceMetrics &metric_data) {
-    auto prometheus_metric_data =
-        PrometheusExporterUtils::TranslateToPrometheus(metric_data, this->populate_target_info_);
+    auto prometheus_metric_data = PrometheusExporterUtils::TranslateToPrometheus(
+        metric_data, this->populate_target_info_, this->populate_otel_scope_);
     for (auto &data : prometheus_metric_data)
       result.emplace_back(data);
     return true;

exporters/prometheus/src/exporter.cc

@@ -31,7 +31,7 @@ PrometheusExporter::PrometheusExporter(const PrometheusExporterOptions &options)
     return;
   }
   collector_ = std::shared_ptr<PrometheusCollector>(
-      new PrometheusCollector(this, options_.populate_target_info));
+      new PrometheusCollector(this, options_.populate_target_info, options_.populate_otel_scope));
 
   exposer_->RegisterCollectable(collector_);
 }

exporters/prometheus/src/exporter_options.cc

@@ -25,7 +25,35 @@ inline const std::string GetPrometheusDefaultHttpEndpoint()
   return exists ? endpoint : kPrometheusEndpointDefault;
 }
 
-PrometheusExporterOptions::PrometheusExporterOptions() : url(GetPrometheusDefaultHttpEndpoint()) {}
+inline bool GetPrometheusPopulateOtelScope()
+{
+  constexpr char kPrometheusPopulateOtelScope[] =
+      "OTEL_CPP_PROMETHEUS_EXPORTER_POPULATE_OTEL_SCOPE";
+
+  bool setting;
+  auto exists =
+      opentelemetry::sdk::common::GetBoolEnvironmentVariable(kPrometheusPopulateOtelScope, setting);
+
+  return exists ? setting : true;
+}
+
+inline bool GetPrometheusPopulateTargetInfo()
+{
+  constexpr char kPrometheusPopulateTargetInfo[] =
+      "OTEL_CPP_PROMETHEUS_EXPORTER_POPULATE_TARGET_INFO";
+
+  bool setting;
+  auto exists = opentelemetry::sdk::common::GetBoolEnvironmentVariable(
+      kPrometheusPopulateTargetInfo, setting);
+
+  return exists ? setting : true;
+}
+
+PrometheusExporterOptions::PrometheusExporterOptions()
+    : url(GetPrometheusDefaultHttpEndpoint()),
+      populate_target_info(GetPrometheusPopulateTargetInfo()),
+      populate_otel_scope(GetPrometheusPopulateOtelScope())
+{}
 
 }  // namespace metrics
 }  // namespace exporter

exporters/prometheus/src/exporter_utils.cc

@@ -105,7 +105,8 @@ std::string SanitizeLabel(std::string label_key)
  */
 std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateToPrometheus(
     const sdk::metrics::ResourceMetrics &data,
-    bool populate_target_info)
+    bool populate_target_info,
+    bool populate_otel_scope)
 {
 
   // initialize output vector
@@ -126,7 +127,7 @@ std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateT
   {
     SetTarget(data,
               data.scope_metric_data_.begin()->metric_data_.begin()->end_ts.time_since_epoch(),
-              (*data.scope_metric_data_.begin()).scope_, &output);
+              populate_otel_scope ? (*data.scope_metric_data_.begin()).scope_ : nullptr, &output);
   }
 
   for (const auto &instrumentation_info : data.scope_metric_data_)
@@ -149,6 +150,9 @@ std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateT
       metric_family.name = MapToPrometheusName(metric_data.instrument_descriptor.name_,
                                                metric_data.instrument_descriptor.unit_, type);
       metric_family.type = type;
+      const opentelemetry::sdk::instrumentationscope::InstrumentationScope *scope =
+          populate_otel_scope ? instrumentation_info.scope_ : nullptr;
+
       for (const auto &point_data_attr : metric_data.point_data_attr_)
       {
         if (type == prometheus_client::MetricType::Histogram)  // Histogram
@@ -167,8 +171,7 @@ std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateT
             sum = static_cast<double>(nostd::get<int64_t>(histogram_point_data.sum_));
           }
           SetData(std::vector<double>{sum, (double)histogram_point_data.count_}, boundaries, counts,
-                  point_data_attr.attributes, instrumentation_info.scope_, time, &metric_family,
-                  data.resource_);
+                  point_data_attr.attributes, scope, time, &metric_family, data.resource_);
         }
         else if (type == prometheus_client::MetricType::Gauge)
         {
@@ -178,16 +181,16 @@ std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateT
             auto last_value_point_data =
                 nostd::get<sdk::metrics::LastValuePointData>(point_data_attr.point_data);
             std::vector<metric_sdk::ValueType> values{last_value_point_data.value_};
-            SetData(values, point_data_attr.attributes, instrumentation_info.scope_, type, time,
-                    &metric_family, data.resource_);
+            SetData(values, point_data_attr.attributes, scope, type, time, &metric_family,
+                    data.resource_);
           }
           else if (nostd::holds_alternative<sdk::metrics::SumPointData>(point_data_attr.point_data))
           {
             auto sum_point_data =
                 nostd::get<sdk::metrics::SumPointData>(point_data_attr.point_data);
             std::vector<metric_sdk::ValueType> values{sum_point_data.value_};
-            SetData(values, point_data_attr.attributes, instrumentation_info.scope_, type, time,
-                    &metric_family, data.resource_);
+            SetData(values, point_data_attr.attributes, scope, type, time, &metric_family,
+                    data.resource_);
           }
           else
           {
@@ -203,8 +206,8 @@ std::vector<prometheus_client::MetricFamily> PrometheusExporterUtils::TranslateT
             auto sum_point_data =
                 nostd::get<sdk::metrics::SumPointData>(point_data_attr.point_data);
             std::vector<metric_sdk::ValueType> values{sum_point_data.value_};
-            SetData(values, point_data_attr.attributes, instrumentation_info.scope_, type, time,
-                    &metric_family, data.resource_);
+            SetData(values, point_data_attr.attributes, scope, type, time, &metric_family,
+                    data.resource_);
           }
           else
           {

exporters/prometheus/test/collector_test.cc

@@ -73,7 +73,7 @@ TEST(PrometheusCollector, BasicTests)
   MockMetricReader *reader     = new MockMetricReader();
   MockMetricProducer *producer = new MockMetricProducer();
   reader->SetMetricProducer(producer);
-  PrometheusCollector collector(reader, true);
+  PrometheusCollector collector(reader, true, true);
   auto data = collector.Collect();
 
   // Collection size should be the same as the size