[CONFIGURATION] File configuration - implement cardinality_limits

CHANGELOG.md

@@ -30,6 +30,9 @@ Increment the:
 * [SEMANTIC CONVENTIONS] Upgrade to semantic conventions 1.39.0
   [#3813](https://github.com/open-telemetry/opentelemetry-cpp/pull/3813)
 
+* [CONFIGURATION] File configuration - implement cardinality_limits
+  [#3820](https://github.com/open-telemetry/opentelemetry-cpp/pull/3820)
+
 Breaking changes:
 
 * [CONFIGURATION] File configuration - remove zipkin

sdk/include/opentelemetry/sdk/configuration/cardinality_limits_configuration.h

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+#pragma once
+
+#include <cstddef>
+
+#include "opentelemetry/version.h"
+
+OPENTELEMETRY_BEGIN_NAMESPACE
+namespace sdk
+{
+namespace configuration
+{
+
+// YAML-SCHEMA: schema/meter_provider.yaml
+// YAML-NODE: CardinalityLimits
+class CardinalityLimitsConfiguration
+{
+public:
+  std::size_t default_limit;
+  // For all limits, 0 means unset, use default_limit
+  std::size_t counter;
+  std::size_t gauge;
+  std::size_t histogram;
+  std::size_t observable_counter;
+  std::size_t observable_gauge;
+  std::size_t observable_up_down_counter;
+  std::size_t up_down_counter;
+};
+
+}  // namespace configuration
+}  // namespace sdk
+OPENTELEMETRY_END_NAMESPACE

sdk/include/opentelemetry/sdk/configuration/configuration_parser.h

@@ -16,6 +16,7 @@
 #include "opentelemetry/sdk/configuration/batch_span_processor_configuration.h"
 #include "opentelemetry/sdk/configuration/boolean_array_attribute_value_configuration.h"
 #include "opentelemetry/sdk/configuration/boolean_attribute_value_configuration.h"
+#include "opentelemetry/sdk/configuration/cardinality_limits_configuration.h"
 #include "opentelemetry/sdk/configuration/configuration.h"
 #include "opentelemetry/sdk/configuration/console_log_record_exporter_configuration.h"
 #include "opentelemetry/sdk/configuration/console_push_metric_exporter_configuration.h"
@@ -210,6 +211,9 @@ class ConfigurationParser
   std::unique_ptr<MetricProducerConfiguration> ParseMetricProducerConfiguration(
       const std::unique_ptr<DocumentNode> &node) const;
 
+  std::unique_ptr<CardinalityLimitsConfiguration> ParseCardinalityLimitsConfiguration(
+      const std::unique_ptr<DocumentNode> &node) const;
+
   std::unique_ptr<PeriodicMetricReaderConfiguration> ParsePeriodicMetricReaderConfiguration(
       const std::unique_ptr<DocumentNode> &node) const;
 

sdk/include/opentelemetry/sdk/configuration/periodic_metric_reader_configuration.h

@@ -6,6 +6,7 @@
 #include <memory>
 #include <vector>
 
+#include "opentelemetry/sdk/configuration/cardinality_limits_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_producer_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_reader_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_reader_configuration_visitor.h"
@@ -18,7 +19,7 @@ namespace sdk
 namespace configuration
 {
 
-// YAML-SCHEMA: schema/meter_provider.json
+// YAML-SCHEMA: schema/meter_provider.yaml
 // YAML-NODE: PeriodicMetricReader
 class PeriodicMetricReaderConfiguration : public MetricReaderConfiguration
 {
@@ -32,6 +33,7 @@ class PeriodicMetricReaderConfiguration : public MetricReaderConfiguration
   std::size_t timeout{0};
   std::unique_ptr<PushMetricExporterConfiguration> exporter;
   std::vector<std::unique_ptr<MetricProducerConfiguration>> producers;
+  std::unique_ptr<CardinalityLimitsConfiguration> cardinality_limits;
 };
 
 }  // namespace configuration

sdk/include/opentelemetry/sdk/configuration/pull_metric_reader_configuration.h

@@ -6,6 +6,7 @@
 #include <memory>
 #include <vector>
 
+#include "opentelemetry/sdk/configuration/cardinality_limits_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_producer_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_reader_configuration.h"
 #include "opentelemetry/sdk/configuration/metric_reader_configuration_visitor.h"
@@ -18,7 +19,7 @@ namespace sdk
 namespace configuration
 {
 
-// YAML-SCHEMA: schema/meter_provider.json
+// YAML-SCHEMA: schema/meter_provider.yaml
 // YAML-NODE: PullMetricReader
 class PullMetricReaderConfiguration : public MetricReaderConfiguration
 {
@@ -30,7 +31,7 @@ class PullMetricReaderConfiguration : public MetricReaderConfiguration
 
   std::unique_ptr<PullMetricExporterConfiguration> exporter;
   std::vector<std::unique_ptr<MetricProducerConfiguration>> producers;
-  // FIXME: cardinality_limits
+  std::unique_ptr<CardinalityLimitsConfiguration> cardinality_limits;
 };
 
 }  // namespace configuration

sdk/src/configuration/configuration_parser.cc

@@ -23,6 +23,7 @@
 #include "opentelemetry/sdk/configuration/batch_span_processor_configuration.h"
 #include "opentelemetry/sdk/configuration/boolean_array_attribute_value_configuration.h"
 #include "opentelemetry/sdk/configuration/boolean_attribute_value_configuration.h"
+#include "opentelemetry/sdk/configuration/cardinality_limits_configuration.h"
 #include "opentelemetry/sdk/configuration/configuration.h"
 #include "opentelemetry/sdk/configuration/configuration_parser.h"
 #include "opentelemetry/sdk/configuration/console_log_record_exporter_configuration.h"
@@ -1006,6 +1007,25 @@ std::unique_ptr<MetricProducerConfiguration> ConfigurationParser::ParseMetricPro
   return model;
 }
 
+std::unique_ptr<CardinalityLimitsConfiguration>
+ConfigurationParser::ParseCardinalityLimitsConfiguration(
+    const std::unique_ptr<DocumentNode> &node) const
+{
+  auto model = std::make_unique<CardinalityLimitsConfiguration>();
+  std::unique_ptr<DocumentNode> child;
+
+  model->default_limit              = node->GetInteger("default", 2000);
+  model->counter                    = node->GetInteger("counter", 0);
+  model->gauge                      = node->GetInteger("gauge", 0);
+  model->histogram                  = node->GetInteger("histogram", 0);
+  model->observable_counter         = node->GetInteger("observable_counter", 0);
+  model->observable_gauge           = node->GetInteger("observable_gauge", 0);
+  model->observable_up_down_counter = node->GetInteger("observable_up_down_counter", 0);
+  model->up_down_counter            = node->GetInteger("up_down_counter", 0);
+
+  return model;
+}
+
 std::unique_ptr<PeriodicMetricReaderConfiguration>
 ConfigurationParser::ParsePeriodicMetricReaderConfiguration(
     const std::unique_ptr<DocumentNode> &node) const
@@ -1029,6 +1049,12 @@ ConfigurationParser::ParsePeriodicMetricReaderConfiguration(
     }
   }
 
+  child = node->GetChildNode("cardinality_limits");
+  if (child)
+  {
+    model->cardinality_limits = ParseCardinalityLimitsConfiguration(child);
+  }
+
   return model;
 }
 
@@ -1052,7 +1078,11 @@ ConfigurationParser::ParsePullMetricReaderConfiguration(
     }
   }
 
-  // FIXME: cardinality_limits
+  child = node->GetChildNode("cardinality_limits");
+  if (child)
+  {
+    model->cardinality_limits = ParseCardinalityLimitsConfiguration(child);
+  }
 
   return model;
 }

sdk/src/configuration/sdk_builder.cc

@@ -1333,6 +1333,11 @@ std::unique_ptr<opentelemetry::sdk::metrics::MetricReader> SdkBuilder::CreatePer
     OTEL_INTERNAL_LOG_WARN("metric producer not supported, ignoring");
   }
 
+  if (model->cardinality_limits != nullptr)
+  {
+    OTEL_INTERNAL_LOG_WARN("cardinality limits not supported, ignoring");
+  }
+
   sdk = opentelemetry::sdk::metrics::PeriodicExportingMetricReaderFactory::Create(
       std::move(exporter_sdk), options);
 
@@ -1351,6 +1356,11 @@ std::unique_ptr<opentelemetry::sdk::metrics::MetricReader> SdkBuilder::CreatePul
     OTEL_INTERNAL_LOG_WARN("metric producer not supported, ignoring");
   }
 
+  if (model->cardinality_limits != nullptr)
+  {
+    OTEL_INTERNAL_LOG_WARN("cardinality limits not supported, ignoring");
+  }
+
   return sdk;
 }
 

sdk/test/configuration/yaml_metrics_test.cc

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "opentelemetry/sdk/configuration/base2_exponential_bucket_histogram_aggregation_configuration.h"
+#include "opentelemetry/sdk/configuration/cardinality_limits_configuration.h"
 #include "opentelemetry/sdk/configuration/configuration.h"
 #include "opentelemetry/sdk/configuration/default_histogram_aggregation.h"
 #include "opentelemetry/sdk/configuration/explicit_bucket_histogram_aggregation_configuration.h"
@@ -108,6 +109,8 @@ file_format: "1.0-metrics"
   ASSERT_NE(periodic->exporter, nullptr);
   auto *exporter = periodic->exporter.get();
   ASSERT_NE(exporter, nullptr);
+  auto *cardinality_limits = periodic->cardinality_limits.get();
+  ASSERT_EQ(cardinality_limits, nullptr);
 }
 
 TEST(YamlMetrics, periodic_reader)
@@ -121,6 +124,15 @@ file_format: "1.0-metrics"
         timeout: 15000
         exporter:
           console:
+        cardinality_limits:
+          default: 100
+          counter: 200
+          gauge: 300
+          histogram: 400
+          observable_counter: 500
+          observable_gauge: 600
+          observable_up_down_counter: 700
+          up_down_counter: 800
 )";
 
   auto config = DoParse(yaml);
@@ -137,6 +149,42 @@ file_format: "1.0-metrics"
   ASSERT_NE(periodic->exporter, nullptr);
   auto *exporter = periodic->exporter.get();
   ASSERT_NE(exporter, nullptr);
+  auto *cardinality_limits = periodic->cardinality_limits.get();
+  ASSERT_NE(cardinality_limits, nullptr);
+  ASSERT_EQ(cardinality_limits->default_limit, 100);
+  ASSERT_EQ(cardinality_limits->counter, 200);
+  ASSERT_EQ(cardinality_limits->gauge, 300);
+  ASSERT_EQ(cardinality_limits->histogram, 400);
+  ASSERT_EQ(cardinality_limits->observable_counter, 500);
+  ASSERT_EQ(cardinality_limits->observable_gauge, 600);
+  ASSERT_EQ(cardinality_limits->observable_up_down_counter, 700);
+  ASSERT_EQ(cardinality_limits->up_down_counter, 800);
+}
+
+TEST(YamlMetrics, default_pull_reader)
+{
+  std::string yaml = R"(
+file_format: "1.0-metrics"
+meter_provider:
+  readers:
+    - pull:
+        exporter:
+          prometheus/development:
+)";
+
+  auto config = DoParse(yaml);
+  ASSERT_NE(config, nullptr);
+  ASSERT_NE(config->meter_provider, nullptr);
+  ASSERT_EQ(config->meter_provider->readers.size(), 1);
+  auto *reader = config->meter_provider->readers[0].get();
+  ASSERT_NE(reader, nullptr);
+  auto *pull =
+      reinterpret_cast<opentelemetry::sdk::configuration::PullMetricReaderConfiguration *>(reader);
+  ASSERT_NE(pull->exporter, nullptr);
+  auto *exporter = pull->exporter.get();
+  ASSERT_NE(exporter, nullptr);
+  auto *cardinality_limits = pull->cardinality_limits.get();
+  ASSERT_EQ(cardinality_limits, nullptr);
 }
 
 TEST(YamlMetrics, pull_reader)
@@ -148,6 +196,15 @@ file_format: "1.0-metrics"
     - pull:
         exporter:
           prometheus/development:
+        cardinality_limits:
+          default: 100
+          counter: 200
+          gauge: 300
+          histogram: 400
+          observable_counter: 500
+          observable_gauge: 600
+          observable_up_down_counter: 700
+          up_down_counter: 800
 )";
 
   auto config = DoParse(yaml);
@@ -161,6 +218,16 @@ file_format: "1.0-metrics"
   ASSERT_NE(pull->exporter, nullptr);
   auto *exporter = pull->exporter.get();
   ASSERT_NE(exporter, nullptr);
+  auto *cardinality_limits = pull->cardinality_limits.get();
+  ASSERT_NE(cardinality_limits, nullptr);
+  ASSERT_EQ(cardinality_limits->default_limit, 100);
+  ASSERT_EQ(cardinality_limits->counter, 200);
+  ASSERT_EQ(cardinality_limits->gauge, 300);
+  ASSERT_EQ(cardinality_limits->histogram, 400);
+  ASSERT_EQ(cardinality_limits->observable_counter, 500);
+  ASSERT_EQ(cardinality_limits->observable_gauge, 600);
+  ASSERT_EQ(cardinality_limits->observable_up_down_counter, 700);
+  ASSERT_EQ(cardinality_limits->up_down_counter, 800);
 }
 
 TEST(YamlMetrics, default_otlp_http)