feat: add ConsoleMetricExporter

experimental/CHANGELOG.md

@@ -8,6 +8,7 @@ All notable changes to experimental packages in this project will be documented
 
 ### :rocket: (Enhancement)
 
+* feature(add-console-metrics-exporter): add ConsoleMetricExporter [#3120](https://github.com/open-telemetry/opentelemetry-js/pull/3120) @weyert
 * feature(prometheus-serialiser): export the unit block when unit is set in metric descriptor [#3066](https://github.com/open-telemetry/opentelemetry-js/pull/3041) @weyert
 
 ### :bug: (Bug Fix)

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

@@ -0,0 +1,62 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { ExportResult, ExportResultCode } from '@opentelemetry/core';
+import { InstrumentType } from '../InstrumentDescriptor';
+import { AggregationTemporality } from './AggregationTemporality';
+import { ResourceMetrics } from './MetricData';
+import { PushMetricExporter } from './MetricExporter';
+
+/* eslint-disable no-console */
+export class ConsoleMetricExporter implements PushMetricExporter {
+  protected _shutdown = false;
+
+  export(metrics: ResourceMetrics, resultCallback: (result: ExportResult) => void): void {
+    if (this._shutdown) {
+      // If the exporter is shutting down, by spec, we need to return FAILED as export result
+      setImmediate(resultCallback, { code: ExportResultCode.FAILED });
+      return;
+    }
+
+    return ConsoleMetricExporter._sendMetrics(metrics, resultCallback);
+  }
+
+  forceFlush(): Promise<void> {
+    return Promise.resolve();
+  }
+
+  selectAggregationTemporality(_instrumentType: InstrumentType): AggregationTemporality {
+    return AggregationTemporality.CUMULATIVE;
+  }
+
+  shutdown(): Promise<void> {
+    this._shutdown = true;
+    return Promise.resolve();
+  }
+
+  private static _sendMetrics(metrics: ResourceMetrics, done: (result: ExportResult) => void): void {
+    for (const scopeMetrics of metrics.scopeMetrics) {
+      for (const metric of scopeMetrics.metrics) {
+        console.dir({
+          descriptor: metric.descriptor,
+          dataPointType: metric.dataPointType,
+          dataPoints: metric.dataPoints
+        });
+      }
+    }
+
+    done({ code: ExportResultCode.SUCCESS });
+  }
+}

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

@@ -18,7 +18,6 @@ import { AggregationTemporality } from './AggregationTemporality';
 import { ResourceMetrics } from './MetricData';
 import {
   ExportResult,
-  ExportResultCode,
 } from '@opentelemetry/core';
 import { InstrumentType } from '../InstrumentDescriptor';
 
@@ -54,30 +53,3 @@ export interface PushMetricExporter {
    */
   shutdown(): Promise<void>;
 }
-
-export class ConsoleMetricExporter implements PushMetricExporter {
-  protected _shutdown = true;
-  private _aggregationTemporality: AggregationTemporality;
-
-  constructor(aggregationTemporality?: AggregationTemporality) {
-    this._aggregationTemporality = aggregationTemporality ?? AggregationTemporality.CUMULATIVE;
-  }
-
-  export(metrics: ResourceMetrics, resultCallback: (result: ExportResult) => void) {
-    return resultCallback({
-      code: ExportResultCode.FAILED,
-      error: new Error('Method not implemented')
-    });
-  }
-
-  selectAggregationTemporality(_instrumentType: InstrumentType) {
-    return this._aggregationTemporality;
-  }
-
-  // nothing to do
-  async forceFlush() {}
-
-  async shutdown() {
-    this._shutdown = true;
-  }
-}

experimental/packages/opentelemetry-sdk-metrics-base/src/index.ts

@@ -22,6 +22,7 @@ export * from './export/MetricProducer';
 export * from './export/MetricReader';
 export * from './export/PeriodicExportingMetricReader';
 export * from './export/InMemoryMetricExporter';
+export * from './export/ConsoleMetricExporter';
 export { InstrumentDescriptor, InstrumentType } from './InstrumentDescriptor';
 export * from './Meter';
 export * from './MeterProvider';

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

@@ -0,0 +1,108 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import * as metrics from '@opentelemetry/api-metrics';
+import { ExportResult } from '@opentelemetry/core';
+import { ConsoleMetricExporter } from '../../src/export/ConsoleMetricExporter';
+import { PeriodicExportingMetricReader } from '../../src/export/PeriodicExportingMetricReader';
+import { ResourceMetrics } from '../../src/export/MetricData';
+import { MeterProvider } from '../../src/MeterProvider';
+import { defaultResource } from '../util';
+import * as assert from 'assert';
+import * as sinon from 'sinon';
+
+
+async function waitForNumberOfExports(exporter: sinon.SinonSpy<[metrics: ResourceMetrics, resultCallback: (result: ExportResult) => void], void>, numberOfExports: number): Promise<void> {
+  if (numberOfExports <= 0) {
+    throw new Error('numberOfExports must be greater than or equal to 0');
+  }
+
+  let totalExports = 0;
+  while (totalExports < numberOfExports) {
+    await new Promise(resolve => setTimeout(resolve, 20));
+    totalExports = exporter.callCount;
+  }
+}
+
+/* eslint-disable no-console */
+describe('ConsoleMetricExporter', () => {
+  let previousConsoleDir: any;
+  let exporter: ConsoleMetricExporter;
+  let meterProvider: MeterProvider;
+  let meterReader: PeriodicExportingMetricReader;
+  let meter: metrics.Meter;
+
+  beforeEach(() => {
+    previousConsoleDir = console.dir;
+    console.dir = () => {};
+
+    exporter = new ConsoleMetricExporter();
+    meterProvider = new MeterProvider({ resource: defaultResource });
+    meter = meterProvider.getMeter('ConsoleMetricExporter', '1.0.0');
+    meterReader = new PeriodicExportingMetricReader({
+      exporter: exporter,
+      exportIntervalMillis: 100,
+      exportTimeoutMillis: 100
+    });
+    meterProvider.addMetricReader(meterReader);
+  });
+
+  afterEach(async () => {
+    console.dir = previousConsoleDir;
+
+    await meterReader.shutdown();
+  });
+
+  it('should export information about metric', async () => {
+    const counter = meter.createCounter('counter_total', {
+      description: 'a test description',
+    });
+    const counterAttribute = { key1: 'attributeValue1' };
+    counter.add(10, counterAttribute);
+    counter.add(10, counterAttribute);
+
+    const histogram = meter.createHistogram('histogram', { description: 'a histogram' });
+    histogram.record(10);
+    histogram.record(100);
+    histogram.record(1000);
+
+    const spyConsole = sinon.spy(console, 'dir');
+    const spyExport = sinon.spy(exporter, 'export');
+
+    await waitForNumberOfExports(spyExport, 1);
+    const resourceMetrics = spyExport.args[0];
+    const firstResourceMetric = resourceMetrics[0];
+    const consoleArgs = spyConsole.args[0];
+    const consoleMetric = consoleArgs[0];
+    const keys = Object.keys(consoleMetric).sort().join(',');
+
+    const expectedKeys = [
+      'dataPointType',
+      'dataPoints',
+      'descriptor',
+    ].join(',');
+
+    assert.ok(firstResourceMetric.resource.attributes.resourceKey === 'my-resource', 'resourceKey');
+    assert.ok(keys === expectedKeys, 'expectedKeys');
+    assert.ok(consoleMetric.descriptor.name === 'counter_total', 'name');
+    assert.ok(consoleMetric.descriptor.description === 'a test description', 'description');
+    assert.ok(consoleMetric.descriptor.type === 'COUNTER', 'type');
+    assert.ok(consoleMetric.descriptor.unit === '', 'unit');
+    assert.ok(consoleMetric.descriptor.valueType === 1, 'valueType');
+    assert.ok(consoleMetric.dataPoints[0].attributes.key1 === 'attributeValue1', 'ensure metric attributes exists');
+
+    assert.ok(spyExport.calledOnce);
+  });
+});