feat(metrics-exporters): configure temporality via env var

experimental/CHANGELOG.md

@@ -9,6 +9,7 @@ All notable changes to experimental packages in this project will be documented
 ### :rocket: (Enhancement)
 
 * feat(sdk-node): configure trace exporter with environment variables [#3143](https://github.com/open-telemetry/opentelemetry-js/pull/3143) @svetlanabrennan
+* feat(metrics-exporters): configure temporality via environment variable [#3305](https://github.com/open-telemetry/opentelemetry-js/pull/3305) @pichlermarc
 
 ### :bug: (Bug Fix)
 

experimental/packages/opentelemetry-exporter-metrics-otlp-grpc/README.md

@@ -17,16 +17,19 @@ npm install --save @opentelemetry/exporter-metrics-otlp-grpc
 ## Service Name
 
 The OpenTelemetry Collector Exporter does not have a service name configuration.
-In order to set the service name, use the `service.name` resource attribute as prescribed in the [OpenTelemetry Resource Semantic Conventions][semconv-resource-service-name].
-To see sample code and documentation for the traces exporter, as well as instructions for using TLS, visit the [Collector Trace Exporter for web and node][trace-exporter-url].
+In order to set the service name, use the `service.name` resource attribute as prescribed in
+the [OpenTelemetry Resource Semantic Conventions][semconv-resource-service-name].
+To see sample code and documentation for the traces exporter, as well as instructions for using TLS, visit
+the [Collector Trace Exporter for web and node][trace-exporter-url].
 
 ## Metrics in Node - GRPC
 
-The OTLPMetricsExporter in Node expects the URL to only be the hostname. It will not work with `/v1/metrics`. All options that work with trace also work with metrics.
+The OTLPMetricsExporter in Node expects the URL to only be the hostname. It will not work with `/v1/metrics`. All
+options that work with trace also work with metrics.
 
 ```js
 const { MeterProvider, PeriodicExportingMetricReader } = require('@opentelemetry/sdk-metrics');
-const { OTLPMetricExporter } =  require('@opentelemetry/exporter-metrics-otlp-grpc');
+const { OTLPMetricExporter } = require('@opentelemetry/exporter-metrics-otlp-grpc');
 const collectorOptions = {
   // url is optional and can be omitted - default is http://localhost:4317
   url: 'http://<collector-hostname>:<port>',
@@ -52,20 +55,24 @@ counter.add(10, { 'key': 'value' });
 
 ## Environment Variable Configuration
 
- | Environment variable | Description |
-  |----------------------|-------------|
-  | OTEL_EXPORTER_OTLP_METRICS_COMPRESSION | The compression type to use on OTLP metric requests. Options include gzip. By default no compression will be used. |
-  | OTEL_EXPORTER_OTLP_COMPRESSION | The compression type to use on OTLP trace, metric, and log requests. Options include gzip. By default no compression will be used. |
-  | OTEL_EXPORTER_OTLP_METRICS_INSECURE | Whether to enable client transport security for the exporter's gRPC connection for metric requests. This option only applies to OTLP/gRPC when an endpoint is provided without the http or https scheme. Options include true or false. By default insecure is false which creates a secure connection. |
-  | OTEL_EXPORTER_OTLP_INSECURE | Whether to enable client transport security for the exporter's gRPC connection for trace, metric and log requests. This option only applies to OTLP/gRPC when an endpoint is provided without the http or https scheme. Options include true or false. By default insecure is false which creates a secure connection. |
-  | OTEL_EXPORTER_OTLP_METRICS_CERTIFICATE | The path to the file containing trusted root certificate to use when verifying an OTLP metric server's TLS credentials. By default the host platform's trusted root certificate is used.|
-  | OTEL_EXPORTER_OTLP_CERTIFICATE | The path to the file containing trusted root certificate to use when verifying an OTLP trace, metric, or log server's TLS credentials. By default the host platform's trusted root certificate is used. |
-  | OTEL_EXPORTER_OTLP_METRICS_CLIENT_KEY | The path to the file containing private client key to use when verifying an OTLP metric client's TLS credentials. Must provide a client certificate/chain when providing a private client key. By default no client key file is used. |
-  | OTEL_EXPORTER_OTLP_CLIENT_KEY | The path to the file containing private client key to use when verifying an OTLP trace, metric or log client's TLS credentials. Must provide a client certificate/chain when providing a private client key. By default no client key file is used. |
-  | OTEL_EXPORTER_OTLP_METRICS_CLIENT_CERTIFICATE | The path to the file containing trusted client certificate/chain for clients private key to use when verifying an OTLP metric server's TLS credentials. Must provide a private client key when providing a certificate/chain. By default no chain file is used. |
-  | OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE | The path to the file containing trusted client certificate/chain for clients private key to use when verifying an OTLP trace, metric and log server's TLS credentials. Must provide a private client key when providing a certificate/chain. By default no chain file is used. |
-
- > Settings configured programmatically take precedence over environment variables. Per-signal environment variables take precedence over non-per-signal environment variables.
+In addition to settings passed to the constructor, the exporter also supports configuration via environment variables:
+
+| Environment variable | Description |
+|----------------------|-------------|
+| OTEL_EXPORTER_OTLP_ENDPOINT | The endpoint to send metrics to. This will also be used for the traces exporter if `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT` is not configured. By default `localhost:4317` will be used. |
+| OTEL_EXPORTER_OTLP_METRICS_ENDPOINT | The endpoint to send metrics to. By default `localhost:4317` will be used. |
+| OTEL_EXPORTER_OTLP_COMPRESSION | The compression type to use on OTLP trace, metric, and log requests. Options include gzip. By default no compression will be used. |
+| OTEL_EXPORTER_OTLP_METRICS_INSECURE | Whether to enable client transport security for the exporter's gRPC connection for metric requests. This option only applies to OTLP/gRPC when an endpoint is provided without the http or https scheme. Options include true or false. By default insecure is false which creates a secure connection. |
+| OTEL_EXPORTER_OTLP_INSECURE | Whether to enable client transport security for the exporter's gRPC connection for trace, metric and log requests. This option only applies to OTLP/gRPC when an endpoint is provided without the http or https scheme. Options include true or false. By default insecure is false which creates a secure connection. |
+| OTEL_EXPORTER_OTLP_METRICS_CERTIFICATE | The path to the file containing trusted root certificate to use when verifying an OTLP metric server's TLS credentials. By default the host platform's trusted root certificate is used.|
+| OTEL_EXPORTER_OTLP_CERTIFICATE | The path to the file containing trusted root certificate to use when verifying an OTLP trace, metric, or log server's TLS credentials. By default the host platform's trusted root certificate is used. |
+| OTEL_EXPORTER_OTLP_METRICS_CLIENT_KEY | The path to the file containing private client key to use when verifying an OTLP metric client's TLS credentials. Must provide a client certificate/chain when providing a private client key. By default no client key file is used. |
+| OTEL_EXPORTER_OTLP_CLIENT_KEY | The path to the file containing private client key to use when verifying an OTLP trace, metric or log client's TLS credentials. Must provide a client certificate/chain when providing a private client key. By default no client key file is used. |
+| OTEL_EXPORTER_OTLP_METRICS_CLIENT_CERTIFICATE | The path to the file containing trusted client certificate/chain for clients private key to use when verifying an OTLP metric server's TLS credentials. Must provide a private client key when providing a certificate/chain. By default no chain file is used. |
+| OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE | The path to the file containing trusted client certificate/chain for clients private key to use when verifying an OTLP trace, metric and log server's TLS credentials. Must provide a private client key when providing a certificate/chain. By default no chain file is used. |
+| OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE | The exporters aggregation temporality preference. Valid values are `cumulative`, and `delta`. `cumulative` selects cumulative temporality for all instrument kinds. `delta` selects delta aggregation temporality for Counter, Asynchronous Counter and Histogram instrument kinds, and selects cumulative aggregation for UpDownCounter and Asynchronous UpDownCounter instrument kinds. By default `cumulative` is used. |
+
+> Settings configured programmatically take precedence over environment variables. Per-signal environment variables take precedence over non-per-signal environment variables.
 
 ## Running opentelemetry-collector locally to see the metrics
 

experimental/packages/opentelemetry-exporter-metrics-otlp-grpc/src/OTLPMetricExporter.ts

@@ -15,7 +15,6 @@
  */
 
 import {
-  defaultOptions,
   OTLPMetricExporterBase,
   OTLPMetricExporterOptions
 } from '@opentelemetry/exporter-metrics-otlp-http';
@@ -33,7 +32,7 @@ import { createExportMetricsServiceRequest, IExportMetricsServiceRequest } from
 
 class OTLPMetricExporterProxy extends OTLPGRPCExporterNodeBase<ResourceMetrics, IExportMetricsServiceRequest> {
 
-  constructor(config: OTLPGRPCExporterConfigNode & OTLPMetricExporterOptions= defaultOptions) {
+  constructor(config?: OTLPGRPCExporterConfigNode & OTLPMetricExporterOptions) {
     super(config);
     const headers = baggageUtils.parseKeyPairsIntoRecord(getEnv().OTEL_EXPORTER_OTLP_METRICS_HEADERS);
     this.metadata ||= new Metadata();
@@ -73,7 +72,7 @@ class OTLPMetricExporterProxy extends OTLPGRPCExporterNodeBase<ResourceMetrics,
  * OTLP-gRPC metric exporter
  */
 export class OTLPMetricExporter extends OTLPMetricExporterBase<OTLPMetricExporterProxy>{
-  constructor(config: OTLPGRPCExporterConfigNode & OTLPMetricExporterOptions = defaultOptions) {
+  constructor(config?: OTLPGRPCExporterConfigNode & OTLPMetricExporterOptions) {
     super(new OTLPMetricExporterProxy(config), config);
   }
 }

experimental/packages/opentelemetry-exporter-metrics-otlp-http/README.md

@@ -17,8 +17,10 @@ npm install --save @opentelemetry/exporter-metrics-otlp-http
 ## Service Name
 
 The OpenTelemetry Collector Metrics Exporter does not have a service name configuration.
-In order to set the service name, use the `service.name` resource attribute as prescribed in the [OpenTelemetry Resource Semantic Conventions][semconv-resource-service-name].
-To see sample code and documentation for the traces exporter, visit the [Collector Trace Exporter for web and node][trace-exporter-url].
+In order to set the service name, use the `service.name` resource attribute as prescribed in
+the [OpenTelemetry Resource Semantic Conventions][semconv-resource-service-name].
+To see sample code and documentation for the traces exporter, visit
+the [Collector Trace Exporter for web and node][trace-exporter-url].
 
 ## Metrics in Web
 
@@ -27,6 +29,7 @@ The OTLPMetricExporter in Web expects the endpoint to end in `/v1/metrics`.
 ```js
 import { MeterProvider, PeriodicExportingMetricReader } from '@opentelemetry/sdk-metrics';
 import { OTLPMetricExporter } from '@opentelemetry/exporter-metrics-otlp-http';
+
 const collectorOptions = {
   url: '<opentelemetry-collector-url>', // url is optional and can be omitted - default is http://localhost:4318/v1/metrics
   headers: {}, // an optional object containing custom headers to be sent with each request
@@ -50,7 +53,7 @@ counter.add(10, { 'key': 'value' });
 
 ```js
 const { MeterProvider, PeriodicExportingMetricReader } = require('@opentelemetry/sdk-metrics');
-const { OTLPMetricExporter } =  require('@opentelemetry/exporter-metrics-otlp-http');
+const { OTLPMetricExporter } = require('@opentelemetry/exporter-metrics-otlp-http');
 const collectorOptions = {
   url: '<opentelemetry-collector-url>', // url is optional and can be omitted - default is http://localhost:4318/v1/metrics
   concurrencyLimit: 1, // an optional limit on pending requests
@@ -70,35 +73,18 @@ counter.add(10, { 'key': 'value' });
 
 ```
 
-## GRPC
-
-For exporting metrics with GRPC please check [exporter-metrics-otlp-grpc][npm-url-grpc]
-
-## PROTOBUF
-
-For exporting metrics with PROTOBUF please check [exporter-metrics-otlp-proto][npm-url-proto]
-
-## Configuration options as environment variables
-
-Instead of providing options to `OTLPMetricExporter` and `OTLPTraceExporter` explicitly, environment variables may be provided instead.
-
-```sh
-OTEL_EXPORTER_OTLP_ENDPOINT=https://localhost:4318
-# this will automatically append the version and signal path
-# e.g. https://localhost:4318/v1/traces for `OTLPTraceExporter` and https://localhost:4318/v1/metrics for `OTLPMetricExporter`
-```
-
-If the trace and metric exporter endpoints have different providers, the env var for per-signal endpoints are available to use
+## Environment Variable Configuration
 
-```sh
-OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=https://trace-service:4318/v1/traces
-OTEL_EXPORTER_OTLP_METRICS_ENDPOINT=https://metric-service:4318/v1/metrics
-# version and signal needs to be explicit
-```
+In addition to settings passed to the constructor, the exporter also supports configuration via environment variables:
 
-> The per-signal endpoints take precedence and overrides `OTEL_EXPORTER_OTLP_ENDPOINT`
+| Environment variable                              | Description                                                                                                                                                                                                                                                                                                                                                                                                                |
+|---------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| OTEL_EXPORTER_OTLP_ENDPOINT                       | The endpoint to send metrics to. This will also be used for the traces exporter if `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT` is not configured. By default `http://localhost:4318` will be used. `/v1/metrics` will be automatically appended to configured values.                                                                                                                                                             |
+| OTEL_EXPORTER_OTLP_METRICS_ENDPOINT               | The endpoint to send metrics to. By default `https://localhost:4318/v1/metrics` will be used. `v1/metrics` will not be appended automatically and has to be added explicitly.                                                                                                                                                                                                                                              |
+| OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE | The exporters aggregation temporality preference. Valid values are `cumulative`, and `delta`. `cumulative` selects cumulative temporality for all instrument kinds. `delta` selects delta aggregation temporality for Counter, Asynchronous Counter and Histogram instrument kinds, and selects cumulative aggregation for UpDownCounter and Asynchronous UpDownCounter instrument kinds. By default `cumulative` is used. |
 
-For more details, see [OpenTelemetry Specification on Protocol Exporter][opentelemetry-spec-protocol-exporter].
+> Settings configured programmatically take precedence over environment variables. Per-signal environment variables take
+> precedence over non-per-signal environment variables.
 
 ## Running opentelemetry-collector locally to see the metrics
 
@@ -110,6 +96,8 @@ For more details, see [OpenTelemetry Specification on Protocol Exporter][opentel
 - For more information on OpenTelemetry, visit: <https://opentelemetry.io/>
 - For more about OpenTelemetry JavaScript: <https://github.com/open-telemetry/opentelemetry-js>
 - For help or feedback on this project, join us in [GitHub Discussions][discussions-url]
+- For exporting metrics via gRPC please check [exporter-metrics-otlp-grpc][npm-url-grpc]
+- For exporting metrics via protobuf please check [exporter-metrics-otlp-proto][npm-url-proto]
 
 ## License
 

experimental/packages/opentelemetry-exporter-metrics-otlp-http/src/OTLPMetricExporterBase.ts

@@ -14,17 +14,23 @@
  * limitations under the License.
  */
 
-import { ExportResult } from '@opentelemetry/core';
+import {
+  ExportResult,
+  getEnv
+} from '@opentelemetry/core';
 import {
   AggregationTemporality,
   AggregationTemporalitySelector,
   InstrumentType,
   PushMetricExporter,
   ResourceMetrics
 } from '@opentelemetry/sdk-metrics';
-import { defaultOptions, OTLPMetricExporterOptions } from './OTLPMetricExporterOptions';
+import {
+  OTLPMetricExporterOptions
+} from './OTLPMetricExporterOptions';
 import { OTLPExporterBase } from '@opentelemetry/otlp-exporter-base';
 import { IExportMetricsServiceRequest } from '@opentelemetry/otlp-transformer';
+import { diag } from '@opentelemetry/api';
 
 export const CumulativeTemporalitySelector: AggregationTemporalitySelector = () => AggregationTemporality.CUMULATIVE;
 
@@ -41,14 +47,33 @@ export const DeltaTemporalitySelector: AggregationTemporalitySelector = (instrum
   }
 };
 
-function chooseTemporalitySelector(temporalityPreference?: AggregationTemporality): AggregationTemporalitySelector {
-  if (temporalityPreference === AggregationTemporality.DELTA) {
+function chooseTemporalitySelectorFromEnvironment() {
+  const env = getEnv();
+  const configuredTemporality = env.OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE.trim().toLowerCase();
+
+  if (configuredTemporality === 'cumulative') {
+    return CumulativeTemporalitySelector;
+  }
+  if (configuredTemporality === 'delta') {
     return DeltaTemporalitySelector;
   }
 
+  diag.warn(`OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE is set to '${env.OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE}', but only 'cumulative' and 'delta' are allowed. Using default ('cumulative') instead.`);
   return CumulativeTemporalitySelector;
 }
 
+function chooseTemporalitySelector(temporalityPreference?: AggregationTemporality): AggregationTemporalitySelector {
+  // Directly passed preference has priority.
+  if (temporalityPreference != null) {
+    if (temporalityPreference === AggregationTemporality.DELTA) {
+      return DeltaTemporalitySelector;
+    }
+    return CumulativeTemporalitySelector;
+  }
+
+  return chooseTemporalitySelectorFromEnvironment();
+}
+
 export class OTLPMetricExporterBase<T extends OTLPExporterBase<OTLPMetricExporterOptions,
   ResourceMetrics,
   IExportMetricsServiceRequest>>
@@ -57,9 +82,9 @@ implements PushMetricExporter {
   protected _aggregationTemporalitySelector: AggregationTemporalitySelector;
 
   constructor(exporter: T,
-    config: OTLPMetricExporterOptions = defaultOptions) {
+    config?: OTLPMetricExporterOptions) {
     this._otlpExporter = exporter;
-    this._aggregationTemporalitySelector = chooseTemporalitySelector(config.temporalityPreference);
+    this._aggregationTemporalitySelector = chooseTemporalitySelector(config?.temporalityPreference);
   }
 
   export(metrics: ResourceMetrics, resultCallback: (result: ExportResult) => void): void {

experimental/packages/opentelemetry-exporter-metrics-otlp-http/src/OTLPMetricExporterOptions.ts

@@ -20,5 +20,3 @@ import { OTLPExporterConfigBase } from '@opentelemetry/otlp-exporter-base';
 export interface OTLPMetricExporterOptions extends OTLPExporterConfigBase {
   temporalityPreference?: AggregationTemporality
 }
-export const defaultExporterTemporality = AggregationTemporality.CUMULATIVE;
-export const defaultOptions = {temporalityPreference: defaultExporterTemporality};