refactor: use temporality enum for selection

examples/metrics-advanced/src/main.rs

@@ -1,9 +1,8 @@
 use opentelemetry::global;
 use opentelemetry::Key;
 use opentelemetry::KeyValue;
-use opentelemetry_sdk::metrics::reader::DeltaTemporalitySelector;
 use opentelemetry_sdk::metrics::{
- Aggregation, Instrument, PeriodicReader, SdkMeterProvider, Stream,
+ data::Temporality, Aggregation, Instrument, PeriodicReader, SdkMeterProvider, Stream,
 };
 use opentelemetry_sdk::{runtime, Resource};
 use std::error::Error;
@@ -47,7 +46,7 @@ fn init_meter_provider() -> opentelemetry_sdk::metrics::SdkMeterProvider {
 
  // Build exporter using Delta Temporality.
  let exporter = opentelemetry_stdout::MetricsExporterBuilder::default()
- .with_temporality_selector(DeltaTemporalitySelector::new())
+ .with_temporality(Temporality::Delta)
  .build();
 
  let reader = PeriodicReader::builder(exporter, runtime::Tokio).build();

examples/metrics-basic/src/main.rs

@@ -1,20 +1,16 @@
 use opentelemetry::global;
 use opentelemetry::KeyValue;
-use opentelemetry_sdk::metrics::{PeriodicReader, SdkMeterProvider};
+use opentelemetry_sdk::metrics::{data::Temporality, PeriodicReader, SdkMeterProvider};
 use opentelemetry_sdk::{runtime, Resource};
 use std::error::Error;
 use std::vec;
 
 fn init_meter_provider() -> opentelemetry_sdk::metrics::SdkMeterProvider {
  let exporter = opentelemetry_stdout::MetricsExporterBuilder::default()
- // Build exporter using Default (Cumulative) Temporality Selector.
- .with_temporality_selector(
- opentelemetry_sdk::metrics::reader::DefaultTemporalitySelector::new(),
- )
- // Build exporter using Delta Temporality Selector.
- // .with_temporality_selector(
- // opentelemetry_sdk::metrics::reader::DeltaTemporalitySelector::new(),
- // )
+ // Build exporter using Default (Cumulative) Temporality.
+ .with_temporality(Temporality::default())
+ // Build exporter using Delta Temporality.
+ // .with_temporality(Temporality::Delta)
  .build();
  let reader = PeriodicReader::builder(exporter, runtime::Tokio).build();
  let provider = SdkMeterProvider::builder()

opentelemetry-otlp/src/exporter/http/mod.rs

@@ -17,8 +17,6 @@ use opentelemetry_proto::transform::trace::tonic::group_spans_by_resource_and_sc
 use opentelemetry_sdk::export::logs::LogBatch;
 #[cfg(feature = "trace")]
 use opentelemetry_sdk::export::trace::SpanData;
-#[cfg(feature = "metrics")]
-use opentelemetry_sdk::metrics::data::ResourceMetrics;
 use prost::Message;
 use std::collections::HashMap;
 use std::env;
@@ -77,9 +75,7 @@ impl Default for HttpConfig {
 ///
 /// ```
 /// # #[cfg(feature="metrics")]
-/// use opentelemetry_sdk::metrics::reader::{
-/// DefaultTemporalitySelector,
-/// };
+/// use opentelemetry_sdk::metrics::data:Temporality;
 ///
 /// # fn main() -> Result<(), Box<dyn std::error::Error>> {
 /// // Create a span exporter you can use to when configuring tracer providers
@@ -91,7 +87,7 @@ impl Default for HttpConfig {
 /// let metrics_exporter = opentelemetry_otlp::new_exporter()
 /// .http()
 /// .build_metrics_exporter(
-/// Box::new(DefaultTemporalitySelector::new()),
+/// Temporality::default(),
 /// )?;
 ///
 /// // Create a log exporter you can use when configuring logger providers
@@ -251,7 +247,7 @@ impl HttpExporterBuilder {
  #[cfg(feature = "metrics")]
  pub fn build_metrics_exporter(
  mut self,
- temporality_selector: Box<dyn opentelemetry_sdk::metrics::reader::TemporalitySelector>,
+ temporality: opentelemetry_sdk::metrics::data::Temporality,
  ) -> opentelemetry::metrics::Result<crate::MetricsExporter> {
  use crate::{
  OTEL_EXPORTER_OTLP_METRICS_ENDPOINT, OTEL_EXPORTER_OTLP_METRICS_HEADERS,
@@ -265,7 +261,7 @@ impl HttpExporterBuilder {
  OTEL_EXPORTER_OTLP_METRICS_HEADERS,
  )?;
 
- Ok(crate::MetricsExporter::new(client, temporality_selector))
+ Ok(crate::MetricsExporter::new(client, temporality))
  }
 }
 
@@ -341,7 +337,7 @@ impl OtlpHttpClient {
  #[cfg(feature = "metrics")]
  fn build_metrics_export_body(
  &self,
- metrics: &mut ResourceMetrics,
+ metrics: &mut opentelemetry_sdk::metrics::data::ResourceMetrics,
  ) -> opentelemetry::metrics::Result<(Vec<u8>, &'static str)> {
  use opentelemetry_proto::tonic::collector::metrics::v1::ExportMetricsServiceRequest;
 

opentelemetry-otlp/src/exporter/tonic/mod.rs

@@ -96,9 +96,7 @@ fn resolve_compression(
 ///
 /// ```no_run
 /// # #[cfg(feature="metrics")]
-/// use opentelemetry_sdk::metrics::reader::{
-/// DefaultTemporalitySelector,
-/// };
+/// use opentelemetry_sdk::metrics::data::Temporality;
 ///
 /// # fn main() -> Result<(), Box<dyn std::error::Error>> {
 /// // Create a span exporter you can use to when configuring tracer providers
@@ -110,7 +108,7 @@ fn resolve_compression(
 /// let metrics_exporter = opentelemetry_otlp::new_exporter()
 /// .tonic()
 /// .build_metrics_exporter(
-/// Box::new(DefaultTemporalitySelector::new()),
+/// Temporality::default(),
 /// )?;
 ///
 /// // Create a log exporter you can use when configuring logger providers
@@ -331,7 +329,7 @@ impl TonicExporterBuilder {
  #[cfg(feature = "metrics")]
  pub fn build_metrics_exporter(
  self,
- temporality_selector: Box<dyn opentelemetry_sdk::metrics::reader::TemporalitySelector>,
+ temporality: opentelemetry_sdk::metrics::data::Temporality,
  ) -> opentelemetry::metrics::Result<crate::MetricsExporter> {
  use crate::MetricsExporter;
  use metrics::TonicMetricsClient;
@@ -345,7 +343,7 @@ impl TonicExporterBuilder {
 
  let client = TonicMetricsClient::new(channel, interceptor, compression);
 
- Ok(MetricsExporter::new(client, temporality_selector))
+ Ok(MetricsExporter::new(client, temporality))
  }
 
  /// Build a new tonic span exporter

opentelemetry-otlp/src/lib.rs

@@ -126,7 +126,7 @@
 //! use opentelemetry::{global, KeyValue, trace::Tracer};
 //! use opentelemetry_sdk::{trace::{self, RandomIdGenerator, Sampler}, Resource};
 //! # #[cfg(feature = "metrics")]
-//! use opentelemetry_sdk::metrics::reader::DefaultTemporalitySelector;
+//! use opentelemetry_sdk::metrics::data::Temporality;
 //! use opentelemetry_otlp::{Protocol, WithExportConfig, ExportConfig};
 //! use std::time::Duration;
 //! # #[cfg(feature = "grpc-tonic")]
@@ -184,7 +184,7 @@
 //! .with_resource(Resource::new(vec![KeyValue::new("service.name", "example")]))
 //! .with_period(Duration::from_secs(3))
 //! .with_timeout(Duration::from_secs(10))
-//! .with_temporality_selector(DefaultTemporalitySelector::new())
+//! .with_temporality(Temporality::default())
 //! .build();
 //! # }
 //!

opentelemetry-otlp/src/metric.rs

@@ -14,8 +14,7 @@ use opentelemetry_sdk::{
  metrics::{
  data::{ResourceMetrics, Temporality},
  exporter::PushMetricsExporter,
- reader::{DefaultTemporalitySelector, DeltaTemporalitySelector, TemporalitySelector},
- InstrumentKind, PeriodicReader, SdkMeterProvider,
+ PeriodicReader, SdkMeterProvider,
  },
  runtime::Runtime,
  Resource,
@@ -47,7 +46,7 @@ impl OtlpPipeline {
  {
  OtlpMetricPipeline {
  rt,
- temporality_selector: None,
+ temporality: None,
  exporter_pipeline: NoExporterConfig(()),
  resource: None,
  period: None,
@@ -75,22 +74,15 @@ pub enum MetricsExporterBuilder {
 
 impl MetricsExporterBuilder {
  /// Build a OTLP metrics exporter with given configuration.
- pub fn build_metrics_exporter(
- self,
- temporality_selector: Box<dyn TemporalitySelector>,
- ) -> Result<MetricsExporter> {
+ pub fn build_metrics_exporter(self, temporality: Temporality) -> Result<MetricsExporter> {
  match self {
  #[cfg(feature = "grpc-tonic")]
- MetricsExporterBuilder::Tonic(builder) => {
- builder.build_metrics_exporter(temporality_selector)
- }
+ MetricsExporterBuilder::Tonic(builder) => builder.build_metrics_exporter(temporality),
  #[cfg(feature = "http-proto")]
- MetricsExporterBuilder::Http(builder) => {
- builder.build_metrics_exporter(temporality_selector)
- }
+ MetricsExporterBuilder::Http(builder) => builder.build_metrics_exporter(temporality),
  #[cfg(not(any(feature = "http-proto", feature = "grpc-tonic")))]
  MetricsExporterBuilder::Unconfigured => {
- drop(temporality_selector);
+ let _ = temporality;
  Err(opentelemetry::metrics::MetricsError::Other(
  "no configured metrics exporter, enable `http-proto` or `grpc-tonic` feature to configure a metrics exporter".into(),
  ))
@@ -119,7 +111,7 @@ impl From<HttpExporterBuilder> for MetricsExporterBuilder {
 /// runtime.
 pub struct OtlpMetricPipeline<RT, EB> {
  rt: RT,
- temporality_selector: Option<Box<dyn TemporalitySelector>>,
+ temporality: Option<Temporality>,
  exporter_pipeline: EB,
  resource: Option<Resource>,
  period: Option<time::Duration>,
@@ -154,23 +146,13 @@ where
  }
  }
 
- /// Build with the given temporality selector
- pub fn with_temporality_selector<T: TemporalitySelector + 'static>(self, selector: T) -> Self {
+ /// Set the [Temporality] of the exporter.
+ pub fn with_temporality(self, temporality: Temporality) -> Self {
  OtlpMetricPipeline {
- temporality_selector: Some(Box::new(selector)),
+ temporality: Some(temporality),
  ..self
  }
  }
-
- /// Build with delta temporality selector.
- ///
- /// This temporality selector is equivalent to OTLP Metrics Exporter's
- /// `Delta` temporality preference (see [its documentation][exporter-docs]).
- ///
- /// [exporter-docs]: https://github.com/open-telemetry/opentelemetry-specification/blob/a1c13d59bb7d0fb086df2b3e1eaec9df9efef6cc/specification/metrics/sdk_exporters/otlp.md#additional-configuration
- pub fn with_delta_temporality(self) -> Self {
- self.with_temporality_selector(DeltaTemporalitySelector::new())
- }
 }
 
 impl<RT> OtlpMetricPipeline<RT, NoExporterConfig>
@@ -185,7 +167,7 @@ where
  OtlpMetricPipeline {
  exporter_pipeline: pipeline.into(),
  rt: self.rt,
- temporality_selector: self.temporality_selector,
+ temporality: self.temporality,
  resource: self.resource,
  period: self.period,
  timeout: self.timeout,
@@ -199,10 +181,9 @@ where
 {
  /// Build MeterProvider
  pub fn build(self) -> Result<SdkMeterProvider> {
- let exporter = self.exporter_pipeline.build_metrics_exporter(
- self.temporality_selector
- .unwrap_or_else(|| Box::new(DefaultTemporalitySelector::new())),
- )?;
+ let exporter = self
+ .exporter_pipeline
+ .build_metrics_exporter(self.temporality.unwrap_or_default())?;
 
  let mut builder = PeriodicReader::builder(exporter, self.rt);
 
@@ -247,7 +228,7 @@ pub trait MetricsClient: fmt::Debug + Send + Sync + 'static {
 /// Export metrics in OTEL format.
 pub struct MetricsExporter {
  client: Box<dyn MetricsClient>,
- temporality_selector: Box<dyn TemporalitySelector>,
+ temporality: Temporality,
 }
 
 impl Debug for MetricsExporter {
@@ -256,12 +237,6 @@ impl Debug for MetricsExporter {
  }
 }
 
-impl TemporalitySelector for MetricsExporter {
- fn temporality(&self, kind: InstrumentKind) -> Temporality {
- self.temporality_selector.temporality(kind)
- }
-}
-
 #[async_trait]
 impl PushMetricsExporter for MetricsExporter {
  async fn export(&self, metrics: &mut ResourceMetrics) -> Result<()> {
@@ -276,17 +251,18 @@ impl PushMetricsExporter for MetricsExporter {
  fn shutdown(&self) -> Result<()> {
  self.client.shutdown()
  }
+
+ fn temporality(&self) -> Temporality {
+ self.temporality
+ }
 }
 
 impl MetricsExporter {
  /// Create a new metrics exporter
- pub fn new(
- client: impl MetricsClient,
- temporality_selector: Box<dyn TemporalitySelector>,
- ) -> MetricsExporter {
+ pub fn new(client: impl MetricsClient, temporality: Temporality) -> MetricsExporter {
  MetricsExporter {
  client: Box::new(client),
- temporality_selector,
+ temporality,
  }
  }
 }

opentelemetry-sdk/benches/metric.rs

@@ -10,7 +10,7 @@ use opentelemetry_sdk::{
  metrics::{
  data::{ResourceMetrics, Temporality},
  new_view,
- reader::{DeltaTemporalitySelector, MetricReader, TemporalitySelector},
+ reader::MetricReader,
  Aggregation, Instrument, InstrumentKind, ManualReader, Pipeline, SdkMeterProvider, Stream,
  View,
  },
@@ -20,12 +20,6 @@ use opentelemetry_sdk::{
 #[derive(Clone, Debug)]
 struct SharedReader(Arc<dyn MetricReader>);
 
-impl TemporalitySelector for SharedReader {
- fn temporality(&self, kind: InstrumentKind) -> Temporality {
- self.0.temporality(kind)
- }
-}
-
 impl MetricReader for SharedReader {
  fn register_pipeline(&self, pipeline: Weak<Pipeline>) {
  self.0.register_pipeline(pipeline)
@@ -42,6 +36,10 @@ impl MetricReader for SharedReader {
  fn shutdown(&self) -> Result<()> {
  self.0.shutdown()
  }
+
+ fn temporality(&self, kind: InstrumentKind) -> Temporality {
+ self.0.temporality(kind)
+ }
 }
 
 // * Summary *
@@ -118,7 +116,7 @@ fn bench_counter(view: Option<Box<dyn View>>, temporality: &str) -> (SharedReade
  } else {
  SharedReader(Arc::new(
  ManualReader::builder()
- .with_temporality_selector(DeltaTemporalitySelector::new())
+ .with_temporality(Temporality::Delta)
  .build(),
  ))
  };

opentelemetry-sdk/src/metrics/data/temporality.rs

@@ -1,16 +1,22 @@
 /// Defines the window that an aggregation was calculated over.
-#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+#[derive(Debug, Copy, Clone, Default, PartialEq, Eq, Hash)]
 #[non_exhaustive]
 pub enum Temporality {
  /// A measurement interval that continues to expand forward in time from a
  /// starting point.
  ///
  /// New measurements are added to all previous measurements since a start time.
+ #[default]
  Cumulative,
 
  /// A measurement interval that resets each cycle.
  ///
  /// Measurements from one cycle are recorded independently, measurements from
  /// other cycles do not affect them.
  Delta,
+
+ /// Configures Synchronous Counter and Histogram instruments to use
+ /// Delta aggregation temporality, which allows them to shed memory
+ /// following a cardinality explosion, thus use less memory.
+ LowMemory,
 }