feat(sdk-logs): implement log creation sdk metrics

CHANGELOG.md

@@ -35,6 +35,7 @@ For notes on migrating to 2.x / 0.200.x see [the upgrade guide](doc/upgrade-to-2
 
 ### :rocket: Features
 
+* feat(sdk-logs): implement log creation metrics  [#6433](https://github.com/open-telemetry/opentelemetry-js/pull/6433) @anuraaga
 * feat(sdk-trace): implement span start/end metrics  [#6213](https://github.com/open-telemetry/opentelemetry-js/pull/6213) @anuraaga
 
 ### :bug: Bug Fixes

experimental/packages/opentelemetry-sdk-node/README.md

@@ -241,6 +241,7 @@ OTEL_NODE_EXPERIMENTAL_SDK_METRICS=true
 Currently a subset of the specified metrics are implemented. See the following
 linkes for details:
 
+- Logger metrics: [LoggerMetrics.ts](../sdk-logs/src/LoggerMetrics.ts)
 - Span metrics: [TracerMetrics.ts](../../../packages/opentelemetry-sdk-trace-base/src/TracerMetrics.ts)
 
 ## Useful links

experimental/packages/opentelemetry-sdk-node/src/sdk.ts

@@ -312,6 +312,12 @@ export class NodeSDK {
             })
           );
 
+    // While SDK metrics are unstable, we require an opt-in.
+    // https://opentelemetry.io/docs/specs/semconv/otel/sdk-metrics/
+    const sdkMetricsEnabled = getBooleanFromEnv(
+      'OTEL_NODE_EXPERIMENTAL_SDK_METRICS'
+    );
+
     if (
       this._meterProviderConfig?.readers &&
       // only register if there is a reader, otherwise we waste compute/memory.
@@ -340,11 +346,6 @@ export class NodeSDK {
 
     // Only register if there is a span processor
     if (spanProcessors.length > 0) {
-      // While SDK metrics are unstable, we require an opt-in.
-      // https://opentelemetry.io/docs/specs/semconv/otel/sdk-metrics/
-      const sdkMetricsEnabled = getBooleanFromEnv(
-        'OTEL_NODE_EXPERIMENTAL_SDK_METRICS'
-      );
       this._tracerProvider = new NodeTracerProvider({
         ...this._configuration,
         resource: this._resource,
@@ -359,6 +360,7 @@ export class NodeSDK {
         ...getLoggerProviderConfigFromEnv(),
         resource: this._resource,
         processors: this._loggerProviderConfig.logRecordProcessors,
+        meterProvider: sdkMetricsEnabled ? this._meterProvider : undefined,
       });
 
       this._loggerProvider = loggerProvider;

experimental/packages/opentelemetry-sdk-node/test/sdk.test.ts

@@ -68,6 +68,7 @@ import { OTLPTraceExporter as OTLPProtoTraceExporter } from '@opentelemetry/expo
 import { OTLPTraceExporter as OTLPGrpcTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';
 import { ZipkinExporter } from '@opentelemetry/exporter-zipkin';
 
+import { NOOP_COUNTER_METRIC } from '../../../../api/src/metrics/NoopMeter';
 import { ATTR_HOST_NAME, ATTR_PROCESS_PID } from '../src/semconv';
 
 function assertDefaultContextManagerRegistered() {
@@ -408,7 +409,7 @@ describe('Node SDK', () => {
       await sdk.shutdown();
     });
 
-    it('should register a meter provider to the tracer provider if both initialized and metrics enabled', async () => {
+    it('should configure components for SDK metrics if enabled', async () => {
       process.env.OTEL_NODE_EXPERIMENTAL_SDK_METRICS = 'true';
       const exporter = new ConsoleMetricExporter();
       const metricReader = new PeriodicExportingMetricReader({
@@ -420,6 +421,9 @@ describe('Node SDK', () => {
       const sdk = new NodeSDK({
         metricReader: metricReader,
         traceExporter: new ConsoleSpanExporter(),
+        logRecordProcessors: [
+          new SimpleLogRecordProcessor(new InMemoryLogRecordExporter()),
+        ],
         autoDetectResources: false,
       });
 
@@ -435,12 +439,18 @@ describe('Node SDK', () => {
         (tracerProvider as any)._config.meterProvider instanceof MeterProvider
       );
 
+      const loggerProvider = setGlobalLoggerProviderSpy.lastCall.args[0];
+      assert.notDeepEqual(
+        (loggerProvider as any)['_sharedState'].loggerMetrics.createdLogs,
+        NOOP_COUNTER_METRIC
+      );
+
       assert.ok(metrics.getMeterProvider() instanceof MeterProvider);
 
       await sdk.shutdown();
     });
 
-    it('should not register a meter provider to the tracer provider if both initialized but metrics disabled', async () => {
+    it('should not configure components for SDK metrics if disabled', async () => {
       const exporter = new ConsoleMetricExporter();
       const metricReader = new PeriodicExportingMetricReader({
         exporter: exporter,
@@ -451,6 +461,9 @@ describe('Node SDK', () => {
       const sdk = new NodeSDK({
         metricReader: metricReader,
         traceExporter: new ConsoleSpanExporter(),
+        logRecordProcessors: [
+          new SimpleLogRecordProcessor(new InMemoryLogRecordExporter()),
+        ],
         autoDetectResources: false,
       });
 
@@ -464,6 +477,12 @@ describe('Node SDK', () => {
       assert.ok(tracerProvider instanceof NodeTracerProvider);
       assert.equal((tracerProvider as any)._config.meterProvider, undefined);
 
+      const loggerProvider = setGlobalLoggerProviderSpy.lastCall.args[0];
+      assert.deepEqual(
+        (loggerProvider as any)['_sharedState'].loggerMetrics.createdLogs,
+        NOOP_COUNTER_METRIC
+      );
+
       assert.ok(metrics.getMeterProvider() instanceof MeterProvider);
 
       await sdk.shutdown();

experimental/packages/sdk-logs/package.json

@@ -73,6 +73,7 @@
     "@babel/core": "7.27.1",
     "@babel/preset-env": "7.27.2",
     "@opentelemetry/api": ">=1.4.0 <1.10.0",
+    "@opentelemetry/sdk-metrics": "2.6.0",
     "@types/mocha": "10.0.10",
     "@types/node": "18.19.130",
     "@types/sinon": "17.0.4",

experimental/packages/sdk-logs/src/Logger.ts

@@ -86,6 +86,7 @@ export class Logger implements logsAPI.Logger {
         ...logRecord,
       }
     );
+    this._sharedState.loggerMetrics.emitLog();
     /**
      * the explicitly passed Context,
      * the current Context, or an empty Context if the Logger was obtained with include_trace_context=false

experimental/packages/sdk-logs/src/LoggerMetrics.ts

@@ -0,0 +1,25 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+import type { Counter, Meter } from '@opentelemetry/api';
+import { METRIC_OTEL_SDK_LOG_CREATED } from './semconv';
+
+/**
+ * Generates `otel.sdk.log.*` metrics.
+ * https://opentelemetry.io/docs/specs/semconv/otel/sdk-metrics/#log-metrics
+ */
+export class LoggerMetrics {
+  private readonly createdLogs: Counter;
+
+  constructor(meter: Meter) {
+    this.createdLogs = meter.createCounter(METRIC_OTEL_SDK_LOG_CREATED, {
+      unit: '{log_record}',
+      description: 'The number of logs submitted to enabled SDK Loggers.',
+    });
+  }
+
+  emitLog() {
+    this.createdLogs.add(1);
+  }
+}

experimental/packages/sdk-logs/src/LoggerProvider.ts

@@ -33,13 +33,15 @@ export class LoggerProvider implements logsAPI.LoggerProvider {
       loggerConfigurator:
         config.loggerConfigurator ?? DEFAULT_LOGGER_CONFIGURATOR,
       processors: config.processors ?? [],
+      meterProvider: config.meterProvider,
     };
     this._sharedState = new LoggerProviderSharedState(
       mergedConfig.resource,
       mergedConfig.forceFlushTimeoutMillis,
       mergedConfig.logRecordLimits,
       mergedConfig.processors,
-      mergedConfig.loggerConfigurator
+      mergedConfig.loggerConfigurator,
+      mergedConfig.meterProvider
     );
     this._shutdownOnce = new BindOnceFuture(this._shutdown, this);
   }

experimental/packages/sdk-logs/src/internal/LoggerProviderSharedState.ts

@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import { type MeterProvider, createNoopMeter } from '@opentelemetry/api';
 import type { Logger } from '@opentelemetry/api-logs';
 import { SeverityNumber } from '@opentelemetry/api-logs';
 import type { Resource } from '@opentelemetry/resources';
@@ -16,6 +17,8 @@ import type {
 import { NoopLogRecordProcessor } from '../export/NoopLogRecordProcessor';
 import { MultiLogRecordProcessor } from '../MultiLogRecordProcessor';
 import { getInstrumentationScopeKey } from './utils';
+import { LoggerMetrics } from '../LoggerMetrics';
+import { VERSION } from '../version';
 
 const DEFAULT_LOGGER_CONFIG: Required<LoggerConfig> = {
   disabled: false,
@@ -38,6 +41,7 @@ export class LoggerProviderSharedState {
   readonly forceFlushTimeoutMillis: number;
   readonly logRecordLimits: Required<LogRecordLimits>;
   readonly processors: LogRecordProcessor[];
+  readonly loggerMetrics: LoggerMetrics;
   private _loggerConfigurator: LoggerConfigurator;
   private _loggerConfigs: Map<string, Required<LoggerConfig>> = new Map();
 
@@ -46,7 +50,8 @@ export class LoggerProviderSharedState {
     forceFlushTimeoutMillis: number,
     logRecordLimits: Required<LogRecordLimits>,
     processors: LogRecordProcessor[],
-    loggerConfigurator?: LoggerConfigurator
+    loggerConfigurator?: LoggerConfigurator,
+    meterProvider?: MeterProvider
   ) {
     this.resource = resource;
     this.forceFlushTimeoutMillis = forceFlushTimeoutMillis;
@@ -64,6 +69,11 @@ export class LoggerProviderSharedState {
 
     this._loggerConfigurator =
       loggerConfigurator ?? DEFAULT_LOGGER_CONFIGURATOR;
+
+    const meter = meterProvider
+      ? meterProvider.getMeter('@opentelemetry/sdk-logs', VERSION)
+      : createNoopMeter();
+    this.loggerMetrics = new LoggerMetrics(meter);
   }
 
   /**

experimental/packages/sdk-logs/src/semconv.ts

@@ -0,0 +1,17 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*
+ * This file contains a copy of unstable semantic convention definitions
+ * used by this package.
+ * @see https://github.com/open-telemetry/opentelemetry-js/tree/main/semantic-conventions#unstable-semconv
+ */
+
+/**
+ * The number of logs submitted to enabled SDK Loggers.
+ *
+ * @experimental This metric is experimental and is subject to breaking changes in minor releases of `@opentelemetry/semantic-conventions`.
+ */
+export const METRIC_OTEL_SDK_LOG_CREATED = 'otel.sdk.log.created' as const;

experimental/packages/sdk-logs/src/types.ts

@@ -6,6 +6,7 @@
 import type { Resource } from '@opentelemetry/resources';
 import type { SeverityNumber } from '@opentelemetry/api-logs';
 import type { InstrumentationScope } from '@opentelemetry/core';
+import type { MeterProvider } from '@opentelemetry/api';
 import type { LogRecordProcessor } from './LogRecordProcessor';
 
 /**
@@ -83,6 +84,12 @@ export interface LoggerProviderConfig {
    * @experimental This feature is in development as per the OpenTelemetry specification.
    */
   loggerConfigurator?: LoggerConfigurator;
+
+  /**
+   * A meter provider to record logs SDK metrics to.
+   * @experimental This option is experimental and is subject to breaking changes in minor releases.
+   */
+  meterProvider?: MeterProvider;
 }
 
 export interface LogRecordLimits {

experimental/packages/sdk-logs/test/common/LoggerProvider.test.ts

@@ -8,6 +8,7 @@ import {
   defaultResource,
   resourceFromAttributes,
 } from '@opentelemetry/resources';
+import { MeterProvider } from '@opentelemetry/sdk-metrics';
 import * as assert from 'assert';
 import * as sinon from 'sinon';
 
@@ -16,6 +17,7 @@ import { NoopLogRecordProcessor } from '../../src/export/NoopLogRecordProcessor'
 import { DEFAULT_LOGGER_NAME } from './../../src/LoggerProvider';
 import { MultiLogRecordProcessor } from '../../src/MultiLogRecordProcessor';
 import { Logger } from '../../src/Logger';
+import { TestMetricReader } from './utils';
 
 describe('LoggerProvider', () => {
   beforeEach(() => {
@@ -303,4 +305,39 @@ describe('LoggerProvider', () => {
       sinon.assert.calledOnce(warnStub);
     });
   });
+
+  describe('LoggerMetrics', () => {
+    it('should record metrics for created logs', async () => {
+      const metricReader = new TestMetricReader();
+      const meterProvider = new MeterProvider({
+        readers: [metricReader],
+      });
+
+      const logRecordProcessor = new NoopLogRecordProcessor();
+      const provider = new LoggerProvider({
+        processors: [logRecordProcessor],
+        meterProvider,
+      });
+      const logger = provider.getLogger('test');
+      logger.emit({ body: 'log 1' });
+      let { resourceMetrics } = await metricReader.collect();
+      let metrics = resourceMetrics.scopeMetrics[0].metrics;
+      let logsCreatedMetric = metrics.find(
+        metric => metric.descriptor.name === 'otel.sdk.log.created'
+      );
+      assert.ok(logsCreatedMetric);
+      assert.strictEqual(logsCreatedMetric.dataPoints[0].value, 1);
+      assert.deepStrictEqual(logsCreatedMetric.dataPoints[0].attributes, {});
+
+      logger.emit({ body: 'log 1' });
+      ({ resourceMetrics } = await metricReader.collect());
+      metrics = resourceMetrics.scopeMetrics[0].metrics;
+      logsCreatedMetric = metrics.find(
+        metric => metric.descriptor.name === 'otel.sdk.log.created'
+      );
+      assert.ok(logsCreatedMetric);
+      assert.strictEqual(logsCreatedMetric.dataPoints[0].value, 2);
+      assert.deepStrictEqual(logsCreatedMetric.dataPoints[0].attributes, {});
+    });
+  });
 });

experimental/packages/sdk-logs/test/common/utils.ts

@@ -3,6 +3,8 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import { MetricReader } from '@opentelemetry/sdk-metrics';
+
 export const validAttributes = {
   string: 'string',
   number: 0,
@@ -19,3 +21,12 @@ export const invalidAttributes = {
   // This empty length attribute should not be set
   '': 'empty-key',
 };
+
+export class TestMetricReader extends MetricReader {
+  protected override onShutdown(): Promise<void> {
+    return Promise.resolve();
+  }
+  protected override onForceFlush(): Promise<void> {
+    return Promise.resolve();
+  }
+}

experimental/packages/sdk-logs/tsconfig.esm.json

@@ -23,6 +23,9 @@
     {
       "path": "../../../packages/opentelemetry-resources"
     },
+    {
+      "path": "../../../packages/sdk-metrics"
+    },
     {
       "path": "../../../semantic-conventions"
     },

experimental/packages/sdk-logs/tsconfig.esnext.json

@@ -23,6 +23,9 @@
     {
       "path": "../../../packages/opentelemetry-resources"
     },
+    {
+      "path": "../../../packages/sdk-metrics"
+    },
     {
       "path": "../../../semantic-conventions"
     },

experimental/packages/sdk-logs/tsconfig.json

@@ -23,6 +23,9 @@
     {
       "path": "../../../packages/opentelemetry-resources"
     },
+    {
+      "path": "../../../packages/sdk-metrics"
+    },
     {
       "path": "../../../semantic-conventions"
     },