feat(sdk-metrics-base): update metric exporter interfaces

experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricExporter.ts

@@ -16,40 +16,34 @@
 
 import { AggregationTemporality } from './AggregationTemporality';
 import { MetricData } from './MetricData';
+import {
+  ExportResult,
+  ExportResultCode,
+} from '@opentelemetry/core';
 
 
 // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#metricexporter
 
-// TODO should this just be an interface and exporters can implement their own shutdown?
-export abstract class MetricExporter {
-  protected _shutdown = false;
+export interface PushMetricExporter {
 
-  abstract export(batch: MetricData[]): Promise<void>;
+  export(batch: MetricData[], resultCallback: (result: ExportResult) => void): void;
 
-  abstract forceFlush(): Promise<void>;
+  forceFlush(): Promise<void>;
 
-  abstract getPreferredAggregationTemporality(): AggregationTemporality;
+  getPreferredAggregationTemporality(): AggregationTemporality;
 
-  async shutdown(): Promise<void> {
-    if (this._shutdown) {
-      return;
-    }
+  shutdown(): Promise<void>;
 
-    // Setting _shutdown before flushing might prevent some exporters from flushing
-    // Waiting until flushing is complete might allow another flush to occur during shutdown
-    const flushPromise = this.forceFlush();
-    this._shutdown = true;
-    await flushPromise;
-  }
-
-  isShutdown() {
-    return this._shutdown;
-  }
 }
 
-export class ConsoleMetricExporter extends MetricExporter {
-  async export(_batch: MetricData[]) {
-    throw new Error('Method not implemented');
+export class ConsoleMetricExporter implements PushMetricExporter {
+  protected _shutdown = true;
+
+  async export(_batch: MetricData[], resultCallback: (result: ExportResult) => void) {
+    return resultCallback({
+        code: ExportResultCode.FAILED,
+        error: new Error('Method not implemented')
+      });
   }
 
   getPreferredAggregationTemporality() {
@@ -58,4 +52,8 @@ export class ConsoleMetricExporter extends MetricExporter {
 
   // nothing to do
   async forceFlush() {}
+
+  async shutdown() {
+    this._shutdown = true;
+  }
 }

experimental/packages/opentelemetry-sdk-metrics-base/src/export/PeriodicExportingMetricReader.ts

@@ -15,12 +15,13 @@
  */
 
 import * as api from '@opentelemetry/api';
+import { ExportResultCode, globalErrorHandler } from '@opentelemetry/core';
 import { MetricReader } from './MetricReader';
-import { MetricExporter } from './MetricExporter';
+import { PushMetricExporter } from './MetricExporter';
 import { callWithTimeout, TimeoutError } from '../utils';
 
 export type PeriodicExportingMetricReaderOptions = {
-  exporter: MetricExporter
+  exporter: PushMetricExporter
   exportIntervalMillis?: number,
   exportTimeoutMillis?: number
 };
@@ -32,7 +33,7 @@ export type PeriodicExportingMetricReaderOptions = {
 export class PeriodicExportingMetricReader extends MetricReader {
   private _interval?: ReturnType<typeof setInterval>;
 
-  private _exporter: MetricExporter;
+  private _exporter: PushMetricExporter;
 
   private readonly _exportInterval: number;
 
@@ -62,7 +63,16 @@ export class PeriodicExportingMetricReader extends MetricReader {
 
   private async _runOnce(): Promise<void> {
     const metrics = await this.collect({});
-    await this._exporter.export(metrics);
+    await this._exporter.export(metrics, result => {
+      if (result.code !== ExportResultCode.SUCCESS) {
+        globalErrorHandler(
+          result.error ??
+            new Error(
+              `PeriodicExportingMetricReader: metrics export failed (status ${result})`
+            )
+        );
+      }
+    });
   }
 
   protected override onInitialized(): void {

experimental/packages/opentelemetry-sdk-metrics-base/test/export/PeriodicExportingMetricReader.test.ts

@@ -16,29 +16,40 @@
 
 import { PeriodicExportingMetricReader } from '../../src/export/PeriodicExportingMetricReader';
 import { AggregationTemporality } from '../../src/export/AggregationTemporality';
-import { MetricExporter } from '../../src';
+import { PushMetricExporter } from '../../src';
 import { MetricData } from '../../src/export/MetricData';
 import * as assert from 'assert';
 import * as sinon from 'sinon';
 import { MetricProducer } from '../../src/export/MetricProducer';
 import { TimeoutError } from '../../src/utils';
+import { ExportResult, ExportResultCode } from '@opentelemetry/core';
 import { assertRejects } from '../test-utils';
 
 const MAX_32_BIT_INT = 2 ** 31 - 1;
 
-class TestMetricExporter extends MetricExporter {
+class TestMetricExporter implements PushMetricExporter {
   public exportTime = 0;
   public forceFlushTime = 0;
   public throwException = false;
   private _batches: MetricData[][] = [];
+  private _shutdown: boolean = false;
 
-  async export(batch: MetricData[]): Promise<void> {
+  async export(batch: MetricData[], resultCallback: (result: ExportResult) => void): Promise<void> {
     this._batches.push(batch);
 
     if (this.throwException) {
       throw new Error('Error during export');
     }
-    await new Promise(resolve => setTimeout(resolve, this.exportTime));
+    setTimeout(() => {
+      resultCallback({code: ExportResultCode.SUCCESS});
+    }, this.exportTime);
+  }
+
+  async shutdown(): Promise<void> {
+    if (this._shutdown) return;
+    const flushPromise = this.forceFlush();
+    this._shutdown = true;
+    await flushPromise;
   }
 
   async forceFlush(): Promise<void> {

experimental/packages/opentelemetry-sdk-metrics-base/test/state/MetricCollector.test.ts

@@ -19,18 +19,22 @@ import * as sinon from 'sinon';
 import { MeterProvider } from '../../src';
 import { AggregationTemporality } from '../../src/export/AggregationTemporality';
 import { MetricData, PointDataType } from '../../src/export/MetricData';
-import { MetricExporter } from '../../src/export/MetricExporter';
+import { PushMetricExporter } from '../../src/export/MetricExporter';
 import { MeterProviderSharedState } from '../../src/state/MeterProviderSharedState';
 import { MetricCollector } from '../../src/state/MetricCollector';
 import { defaultInstrumentationLibrary, defaultResource, assertMetricData, assertPointData } from '../util';
 import { TestMetricReader } from '../export/TestMetricReader';
+import { ExportResult, ExportResultCode } from '@opentelemetry/core';
 
-class TestMetricExporter extends MetricExporter {
+class TestMetricExporter implements PushMetricExporter {
   metricDataList: MetricData[] = [];
-  async export(batch: MetricData[]): Promise<void> {
+  async export(batch: MetricData[], resultCallback: (result: ExportResult) => void): Promise<void> {
     this.metricDataList.push(...batch);
+    resultCallback({code: ExportResultCode.SUCCESS});
   }
 
+  async shutdown(): Promise<void> {}
+
   async forceFlush(): Promise<void> {}
 
   getPreferredAggregationTemporality(): AggregationTemporality {
@@ -63,7 +67,8 @@ describe('MetricCollector', () => {
   });
 
   describe('collect', () => {
-    function setupInstruments(exporter: MetricExporter) {
+
+    function setupInstruments(exporter: PushMetricExporter) {
       const meterProvider = new MeterProvider({ resource: defaultResource });
 
       const reader = new TestMetricReader(exporter.getPreferredAggregationTemporality());