[Metrics API/SDK] Change Meter API/SDK to return nostd::unique_ptr for Sync Instruments

api/include/opentelemetry/metrics/meter.h

@@ -9,6 +9,7 @@
 # include "opentelemetry/nostd/shared_ptr.h"
 # include "opentelemetry/nostd/span.h"
 # include "opentelemetry/nostd/string_view.h"
+# include "opentelemetry/nostd/unique_ptr.h"
 # include "opentelemetry/version.h"
 
 OPENTELEMETRY_BEGIN_NAMESPACE
@@ -28,20 +29,20 @@ class Meter
  virtual ~Meter() = default;
 
  /**
- * Creates a Counter with the passed characteristics and returns a shared_ptr to that Counter.
+ * Creates a Counter with the passed characteristics and returns a unique_ptr to that Counter.
  *
  * @param name the name of the new Counter.
  * @param description a brief description of what the Counter is used for.
  * @param unit the unit of metric values following https://unitsofmeasure.org/ucum.html.
  * @return a shared pointer to the created Counter.
  */
 
- virtual nostd::shared_ptr<Counter<long>> CreateLongCounter(
+ virtual nostd::unique_ptr<Counter<long>> CreateLongCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;
 
- virtual nostd::shared_ptr<Counter<double>> CreateDoubleCounter(
+ virtual nostd::unique_ptr<Counter<double>> CreateDoubleCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;
@@ -65,19 +66,19 @@ class Meter
  nostd::string_view unit = "") noexcept = 0;
 
  /**
- * Creates a Histogram with the passed characteristics and returns a shared_ptr to that Histogram.
+ * Creates a Histogram with the passed characteristics and returns a unique_ptr to that Histogram.
  *
  * @param name the name of the new Histogram.
  * @param description a brief description of what the Histogram is used for.
  * @param unit the unit of metric values following https://unitsofmeasure.org/ucum.html.
  * @return a shared pointer to the created Histogram.
  */
- virtual nostd::shared_ptr<Histogram<long>> CreateLongHistogram(
+ virtual nostd::unique_ptr<Histogram<long>> CreateLongHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;
 
- virtual nostd::shared_ptr<Histogram<double>> CreateDoubleHistogram(
+ virtual nostd::unique_ptr<Histogram<double>> CreateDoubleHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;
@@ -101,20 +102,20 @@ class Meter
  nostd::string_view unit = "") noexcept = 0;
 
  /**
- * Creates an UpDownCounter with the passed characteristics and returns a shared_ptr to that
+ * Creates an UpDownCounter with the passed characteristics and returns a unique_ptr to that
  * UpDownCounter.
  *
  * @param name the name of the new UpDownCounter.
  * @param description a brief description of what the UpDownCounter is used for.
  * @param unit the unit of metric values following https://unitsofmeasure.org/ucum.html.
  * @return a shared pointer to the created UpDownCounter.
  */
- virtual nostd::shared_ptr<UpDownCounter<long>> CreateLongUpDownCounter(
+ virtual nostd::unique_ptr<UpDownCounter<long>> CreateLongUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;
 
- virtual nostd::shared_ptr<UpDownCounter<double>> CreateDoubleUpDownCounter(
+ virtual nostd::unique_ptr<UpDownCounter<double>> CreateDoubleUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept = 0;

api/include/opentelemetry/metrics/noop.h

@@ -87,19 +87,19 @@ class NoopObservableInstrument : public ObservableInstrument
 class NoopMeter final : public Meter
 {
 public:
- nostd::shared_ptr<Counter<long>> CreateLongCounter(nostd::string_view name,
+ nostd::unique_ptr<Counter<long>> CreateLongCounter(nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<Counter<long>>{new NoopCounter<long>(name, description, unit)};
+ return nostd::unique_ptr<Counter<long>>{new NoopCounter<long>(name, description, unit)};
  }
 
- nostd::shared_ptr<Counter<double>> CreateDoubleCounter(
+ nostd::unique_ptr<Counter<double>> CreateDoubleCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<Counter<double>>{new NoopCounter<double>(name, description, unit)};
+ return nostd::unique_ptr<Counter<double>>{new NoopCounter<double>(name, description, unit)};
  }
 
  nostd::shared_ptr<ObservableInstrument> CreateLongObservableCounter(
@@ -120,20 +120,20 @@ class NoopMeter final : public Meter
  new NoopObservableInstrument(name, description, unit));
  }
 
- nostd::shared_ptr<Histogram<long>> CreateLongHistogram(
+ nostd::unique_ptr<Histogram<long>> CreateLongHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<Histogram<long>>{new NoopHistogram<long>(name, description, unit)};
+ return nostd::unique_ptr<Histogram<long>>{new NoopHistogram<long>(name, description, unit)};
  }
 
- nostd::shared_ptr<Histogram<double>> CreateDoubleHistogram(
+ nostd::unique_ptr<Histogram<double>> CreateDoubleHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<Histogram<double>>{new NoopHistogram<double>(name, description, unit)};
+ return nostd::unique_ptr<Histogram<double>>{new NoopHistogram<double>(name, description, unit)};
  }
 
  nostd::shared_ptr<ObservableInstrument> CreateLongObservableGauge(
@@ -154,21 +154,21 @@ class NoopMeter final : public Meter
  new NoopObservableInstrument(name, description, unit));
  }
 
- nostd::shared_ptr<UpDownCounter<long>> CreateLongUpDownCounter(
+ nostd::unique_ptr<UpDownCounter<long>> CreateLongUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<UpDownCounter<long>>{
+ return nostd::unique_ptr<UpDownCounter<long>>{
  new NoopUpDownCounter<long>(name, description, unit)};
  }
 
- nostd::shared_ptr<UpDownCounter<double>> CreateDoubleUpDownCounter(
+ nostd::unique_ptr<UpDownCounter<double>> CreateDoubleUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override
  {
- return nostd::shared_ptr<UpDownCounter<double>>{
+ return nostd::unique_ptr<UpDownCounter<double>>{
  new NoopUpDownCounter<double>(name, description, unit)};
  }
 

sdk/include/opentelemetry/sdk/metrics/meter.h

@@ -35,12 +35,12 @@ class Meter final : public opentelemetry::metrics::Meter
  std::unique_ptr<opentelemetry::sdk::instrumentationscope::InstrumentationScope> scope =
  opentelemetry::sdk::instrumentationscope::InstrumentationScope::Create("")) noexcept;
 
- nostd::shared_ptr<opentelemetry::metrics::Counter<long>> CreateLongCounter(
+ nostd::unique_ptr<opentelemetry::metrics::Counter<long>> CreateLongCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
 
- nostd::shared_ptr<opentelemetry::metrics::Counter<double>> CreateDoubleCounter(
+ nostd::unique_ptr<opentelemetry::metrics::Counter<double>> CreateDoubleCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
@@ -55,12 +55,12 @@ class Meter final : public opentelemetry::metrics::Meter
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
 
- nostd::shared_ptr<opentelemetry::metrics::Histogram<long>> CreateLongHistogram(
+ nostd::unique_ptr<opentelemetry::metrics::Histogram<long>> CreateLongHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
 
- nostd::shared_ptr<opentelemetry::metrics::Histogram<double>> CreateDoubleHistogram(
+ nostd::unique_ptr<opentelemetry::metrics::Histogram<double>> CreateDoubleHistogram(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
@@ -75,12 +75,12 @@ class Meter final : public opentelemetry::metrics::Meter
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
 
- nostd::shared_ptr<opentelemetry::metrics::UpDownCounter<long>> CreateLongUpDownCounter(
+ nostd::unique_ptr<opentelemetry::metrics::UpDownCounter<long>> CreateLongUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;
 
- nostd::shared_ptr<opentelemetry::metrics::UpDownCounter<double>> CreateDoubleUpDownCounter(
+ nostd::unique_ptr<opentelemetry::metrics::UpDownCounter<double>> CreateDoubleUpDownCounter(
  nostd::string_view name,
  nostd::string_view description = "",
  nostd::string_view unit = "") noexcept override;

sdk/src/metrics/meter.cc

@@ -33,19 +33,19 @@ Meter::Meter(
  observable_registry_(new ObservableRegistry())
 {}
 
-nostd::shared_ptr<metrics::Counter<long>> Meter::CreateLongCounter(nostd::string_view name,
+nostd::unique_ptr<metrics::Counter<long>> Meter::CreateLongCounter(nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
 {
  InstrumentDescriptor instrument_descriptor = {
  std::string{name.data(), name.size()}, std::string{description.data(), description.size()},
  std::string{unit.data(), unit.size()}, InstrumentType::kCounter, InstrumentValueType::kLong};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::Counter<long>>(
+ return nostd::unique_ptr<metrics::Counter<long>>(
  new LongCounter(instrument_descriptor, std::move(storage)));
 }
 
-nostd::shared_ptr<metrics::Counter<double>> Meter::CreateDoubleCounter(
+nostd::unique_ptr<metrics::Counter<double>> Meter::CreateDoubleCounter(
  nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
@@ -55,7 +55,7 @@ nostd::shared_ptr<metrics::Counter<double>> Meter::CreateDoubleCounter(
  std::string{unit.data(), unit.size()}, InstrumentType::kCounter,
  InstrumentValueType::kDouble};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::Counter<double>>{
+ return nostd::unique_ptr<metrics::Counter<double>>{
  new DoubleCounter(instrument_descriptor, std::move(storage))};
 }
 
@@ -87,7 +87,7 @@ Meter::CreateDoubleObservableCounter(nostd::string_view name,
  new ObservableInstrument(instrument_descriptor, std::move(storage), observable_registry_)};
 }
 
-nostd::shared_ptr<metrics::Histogram<long>> Meter::CreateLongHistogram(
+nostd::unique_ptr<metrics::Histogram<long>> Meter::CreateLongHistogram(
  nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
@@ -97,11 +97,11 @@ nostd::shared_ptr<metrics::Histogram<long>> Meter::CreateLongHistogram(
  std::string{unit.data(), unit.size()}, InstrumentType::kHistogram,
  InstrumentValueType::kLong};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::Histogram<long>>{
+ return nostd::unique_ptr<metrics::Histogram<long>>{
  new LongHistogram(instrument_descriptor, std::move(storage))};
 }
 
-nostd::shared_ptr<metrics::Histogram<double>> Meter::CreateDoubleHistogram(
+nostd::unique_ptr<metrics::Histogram<double>> Meter::CreateDoubleHistogram(
  nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
@@ -111,7 +111,7 @@ nostd::shared_ptr<metrics::Histogram<double>> Meter::CreateDoubleHistogram(
  std::string{unit.data(), unit.size()}, InstrumentType::kHistogram,
  InstrumentValueType::kDouble};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::Histogram<double>>{
+ return nostd::unique_ptr<metrics::Histogram<double>>{
  new DoubleHistogram(instrument_descriptor, std::move(storage))};
 }
 
@@ -143,7 +143,7 @@ nostd::shared_ptr<opentelemetry::metrics::ObservableInstrument> Meter::CreateDou
  new ObservableInstrument(instrument_descriptor, std::move(storage), observable_registry_)};
 }
 
-nostd::shared_ptr<metrics::UpDownCounter<long>> Meter::CreateLongUpDownCounter(
+nostd::unique_ptr<metrics::UpDownCounter<long>> Meter::CreateLongUpDownCounter(
  nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
@@ -153,11 +153,11 @@ nostd::shared_ptr<metrics::UpDownCounter<long>> Meter::CreateLongUpDownCounter(
  std::string{unit.data(), unit.size()}, InstrumentType::kUpDownCounter,
  InstrumentValueType::kLong};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::UpDownCounter<long>>{
+ return nostd::unique_ptr<metrics::UpDownCounter<long>>{
  new LongUpDownCounter(instrument_descriptor, std::move(storage))};
 }
 
-nostd::shared_ptr<metrics::UpDownCounter<double>> Meter::CreateDoubleUpDownCounter(
+nostd::unique_ptr<metrics::UpDownCounter<double>> Meter::CreateDoubleUpDownCounter(
  nostd::string_view name,
  nostd::string_view description,
  nostd::string_view unit) noexcept
@@ -167,7 +167,7 @@ nostd::shared_ptr<metrics::UpDownCounter<double>> Meter::CreateDoubleUpDownCount
  std::string{unit.data(), unit.size()}, InstrumentType::kUpDownCounter,
  InstrumentValueType::kDouble};
  auto storage = RegisterSyncMetricStorage(instrument_descriptor);
- return nostd::shared_ptr<metrics::UpDownCounter<double>>{
+ return nostd::unique_ptr<metrics::UpDownCounter<double>>{
  new DoubleUpDownCounter(instrument_descriptor, std::move(storage))};
 }
 

sdk/test/metrics/BUILD

@@ -1,5 +1,20 @@
 load("//bazel:otel_cc_benchmark.bzl", "otel_cc_benchmark")
 
+cc_test(
+ name = "meter_test",
+ srcs = [
+ "meter_test.cc",
+ ],
+ tags = [
+ "metrics",
+ "test",
+ ],
+ deps = [
+ "//sdk/src/metrics",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
 cc_test(
  name = "meter_provider_sdk_test",
  srcs = [
@@ -112,6 +127,21 @@ cc_test(
  ],
 )
 
+cc_test(
+ name = "async_instruments_test",
+ srcs = [
+ "async_instruments_test.cc",
+ ],
+ tags = [
+ "metrics",
+ "test",
+ ],
+ deps = [
+ "//sdk/src/metrics",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
 cc_test(
  name = "async_metric_storage_test",
  srcs = [

sdk/test/metrics/meter_test.cc

@@ -82,12 +82,12 @@ TEST(MeterTest, StressMultiThread)
  MetricReader *metric_reader_ptr = nullptr;
  auto meter = InitMeter(&metric_reader_ptr, "stress_test_meter");
  std::atomic<unsigned> threadCount(0);
- size_t numIterations = MAX_ITERATIONS_MT;
+ std::atomic<size_t> numIterations(MAX_ITERATIONS_MT);
  std::atomic<bool> do_collect{false}, do_sync_create{true}, do_async_create{false};
  std::vector<nostd::shared_ptr<opentelemetry::metrics::ObservableInstrument>>
  observable_instruments;
  std::vector<std::thread> meter_operation_threads;
- size_t instrument_id = 0;
+ std::atomic<size_t> instrument_id(0);
  while (numIterations--)
  {
  for (size_t i = 0; i < MAX_THREADS; i++)