feat(tracing): auto flush BatchSpanProcessor on browser

packages/opentelemetry-tracing/karma.conf.js

@@ -19,6 +19,8 @@ const karmaBaseConfig = require('../../karma.base');
 
 module.exports = (config) => {
   config.set(Object.assign({}, karmaBaseConfig, {
-    webpack: karmaWebpackConfig
+    webpack: karmaWebpackConfig,
+    files: ['test/browser/index-webpack.ts'],
+    preprocessors: { 'test/browser/index-webpack.ts': ['webpack'] }
   }))
 };

packages/opentelemetry-tracing/package.json

@@ -14,7 +14,7 @@
   "scripts": {
     "compile": "tsc --build tsconfig.json tsconfig.esm.json",
     "clean": "tsc --build --clean tsconfig.json tsconfig.esm.json",
-    "test": "nyc ts-mocha -p tsconfig.json 'test/**/*.test.ts' --exclude 'test/index-webpack.ts'",
+    "test": "nyc ts-mocha -p tsconfig.json 'test/**/*.test.ts' --exclude 'test/browser/**/*.ts'",
     "test:browser": "nyc karma start --single-run",
     "tdd": "npm run tdd:node",
     "tdd:node": "npm run test -- --watch-extensions ts --watch",

packages/opentelemetry-tracing/src/BasicTracerProvider.ts

@@ -37,7 +37,7 @@ import { SDKRegistrationConfig, TracerConfig } from './types';
 // eslint-disable-next-line @typescript-eslint/no-var-requires
 const merge = require('lodash.merge');
 import { SpanExporter } from './export/SpanExporter';
-import { BatchSpanProcessor } from './export/BatchSpanProcessor';
+import { BatchSpanProcessor } from './platform';
 
 export type PROPAGATOR_FACTORY = () => TextMapPropagator;
 export type EXPORTER_FACTORY = () => SpanExporter;

packages/opentelemetry-tracing/src/export/BatchSpanProcessor.ts → packages/opentelemetry-tracing/src/export/BatchSpanProcessorBase.ts

@@ -32,7 +32,7 @@ import { SpanExporter } from './SpanExporter';
  * Implementation of the {@link SpanProcessor} that batches spans exported by
  * the SDK then pushes them to the exporter pipeline.
  */
-export class BatchSpanProcessor implements SpanProcessor {
+export abstract class BatchSpanProcessorBase<T extends BufferConfig> implements SpanProcessor {
   private readonly _maxExportBatchSize: number;
   private readonly _maxQueueSize: number;
   private readonly _scheduledDelayMillis: number;
@@ -43,24 +43,26 @@ export class BatchSpanProcessor implements SpanProcessor {
   private _isShutdown = false;
   private _shuttingDownPromise: Promise<void> = Promise.resolve();
 
-  constructor(private readonly _exporter: SpanExporter, config?: BufferConfig) {
+  constructor(private readonly _exporter: SpanExporter, config?: T) {
     const env = getEnv();
     this._maxExportBatchSize =
       typeof config?.maxExportBatchSize === 'number'
         ? config.maxExportBatchSize
         : env.OTEL_BSP_MAX_EXPORT_BATCH_SIZE;
     this._maxQueueSize =
       typeof config?.maxQueueSize === 'number'
-        ? config?.maxQueueSize
+        ? config.maxQueueSize
         : env.OTEL_BSP_MAX_QUEUE_SIZE;
     this._scheduledDelayMillis =
       typeof config?.scheduledDelayMillis === 'number'
-        ? config?.scheduledDelayMillis
+        ? config.scheduledDelayMillis
         : env.OTEL_BSP_SCHEDULE_DELAY;
     this._exportTimeoutMillis =
       typeof config?.exportTimeoutMillis === 'number'
-        ? config?.exportTimeoutMillis
+        ? config.exportTimeoutMillis
         : env.OTEL_BSP_EXPORT_TIMEOUT;
+
+    this.onInit(config);
   }
 
   forceFlush(): Promise<void> {
@@ -87,6 +89,9 @@ export class BatchSpanProcessor implements SpanProcessor {
     this._isShutdown = true;
     this._shuttingDownPromise = new Promise((resolve, reject) => {
       Promise.resolve()
+        .then(() => {
+          return this.onShutdown();
+        })
         .then(() => {
           return this._flushAll();
         })
@@ -190,4 +195,7 @@ export class BatchSpanProcessor implements SpanProcessor {
       this._timer = undefined;
     }
   }
+
+  abstract onInit(config?: T): void;
+  abstract onShutdown(): void;
 }

packages/opentelemetry-tracing/src/index.ts

@@ -16,8 +16,8 @@
 
 export * from './Tracer';
 export * from './BasicTracerProvider';
+export * from './platform';
 export * from './export/ConsoleSpanExporter';
-export * from './export/BatchSpanProcessor';
 export * from './export/InMemorySpanExporter';
 export * from './export/ReadableSpan';
 export * from './export/SimpleSpanProcessor';

packages/opentelemetry-tracing/src/platform/browser/export/BatchSpanProcessor.ts

@@ -0,0 +1,39 @@
+/*
+ * 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 { BatchSpanProcessorBase } from '../../../export/BatchSpanProcessorBase';
+import { BatchSpanProcessorBrowserConfig } from '../../../types';
+
+export class BatchSpanProcessor extends BatchSpanProcessorBase<BatchSpanProcessorBrowserConfig> {
+  private _visibilityChangeListener?: () => void
+
+  onInit(config?: BatchSpanProcessorBrowserConfig): void {
+    if (config?.flushOnDocumentBecomesHidden !== false && document != null) {
+      this._visibilityChangeListener = () => {
+        if (document.visibilityState === 'hidden') {
+          void this.forceFlush();
+        }
+      }
+      document.addEventListener('visibilitychange', this._visibilityChangeListener);
+    }
+  }
+
+  onShutdown(): void {
+    if (this._visibilityChangeListener) {
+      document.removeEventListener('visibilitychange', this._visibilityChangeListener);
+    }
+  }
+}

packages/opentelemetry-tracing/src/platform/browser/index.ts

@@ -0,0 +1,17 @@
+/*
+ * 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.
+ */
+
+export * from './export/BatchSpanProcessor';

packages/opentelemetry-tracing/src/platform/index.ts

@@ -0,0 +1,17 @@
+/*
+ * 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.
+ */
+
+export * from './node';

packages/opentelemetry-tracing/src/platform/node/export/BatchSpanProcessor.ts

@@ -0,0 +1,24 @@
+/*
+ * 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 { BatchSpanProcessorBase } from '../../../export/BatchSpanProcessorBase';
+import { BufferConfig } from '../../../types';
+
+export class BatchSpanProcessor extends BatchSpanProcessorBase<BufferConfig> {
+  onInit(): void {}
+
+  onShutdown(): void {}
+}

packages/opentelemetry-tracing/src/platform/node/index.ts

@@ -0,0 +1,17 @@
+/*
+ * 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.
+ */
+
+export * from './export/BatchSpanProcessor';

packages/opentelemetry-tracing/src/types.ts

@@ -89,3 +89,10 @@ export interface BufferConfig {
    * The default value is 2048. */
   maxQueueSize?: number;
 }
+
+/** Interface configuration for BatchSpanProcessor on browser */
+export interface BatchSpanProcessorBrowserConfig extends BufferConfig {
+  /** Force flush when a user navigates to a new page, closes the tab or the browser, or,
+   * on mobile, switches to a different app. The default value is `true`. */
+  flushOnDocumentBecomesHidden?: boolean;
+}

packages/opentelemetry-tracing/test/browser/export/BatchSpanProcessor.test.ts

@@ -0,0 +1,89 @@
+/*
+ * 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 assert from 'assert';
+import * as sinon from 'sinon';
+import { BatchSpanProcessor, SpanExporter } from '../../../src';
+import { TestTracingSpanExporter } from '../../common/export/TestTracingSpanExporter';
+
+describe('BatchSpanProcessor - web', () => {
+  let visibilityState: VisibilityState = 'visible';
+  let exporter: SpanExporter
+  let processor: BatchSpanProcessor;
+  let forceFlushSpy: sinon.SinonStub;
+  let visibilityChangeEvent: Event;
+
+  beforeEach(() => {
+    sinon.replaceGetter(document, 'visibilityState', () => visibilityState);
+    visibilityState = 'visible';
+    exporter = new TestTracingSpanExporter();
+    processor = new BatchSpanProcessor(exporter, {});
+    forceFlushSpy = sinon.stub(processor, 'forceFlush');
+    visibilityChangeEvent = new Event('visibilitychange');
+  });
+
+  afterEach(() => {
+    processor.onShutdown();
+    sinon.restore();
+  });
+
+  describe('when document becomes hidden', () => {
+    it('should force flush spans', () => {
+      assert.strictEqual(forceFlushSpy.callCount, 0);
+      visibilityState = 'hidden';
+      document.dispatchEvent(visibilityChangeEvent);
+      assert.strictEqual(forceFlushSpy.callCount, 1);
+    });
+
+    describe('AND shutdown has been called', () => {
+      it('should NOT force flush spans', async () => {
+        assert.strictEqual(forceFlushSpy.callCount, 0);
+        await processor.shutdown();
+        visibilityState = 'hidden';
+        document.dispatchEvent(visibilityChangeEvent);
+        assert.strictEqual(forceFlushSpy.callCount, 0);
+      });
+    })
+
+    describe('AND flushOnDocumentBecomesHidden configuration option', () => {
+      it('set to true should force flush spans', () => {
+        processor = new BatchSpanProcessor(exporter, { flushOnDocumentBecomesHidden: true });
+        forceFlushSpy = sinon.stub(processor, 'forceFlush');
+        assert.strictEqual(forceFlushSpy.callCount, 0);
+        visibilityState = 'hidden';
+        document.dispatchEvent(visibilityChangeEvent);
+        assert.strictEqual(forceFlushSpy.callCount, 1);
+      })
+
+      it('set to false should NOT force flush spans', () => {
+        processor = new BatchSpanProcessor(exporter, { flushOnDocumentBecomesHidden: false });
+        forceFlushSpy = sinon.stub(processor, 'forceFlush');
+        assert.strictEqual(forceFlushSpy.callCount, 0);
+        visibilityState = 'hidden';
+        document.dispatchEvent(visibilityChangeEvent);
+        assert.strictEqual(forceFlushSpy.callCount, 0);
+      })
+    })
+  })
+
+  describe('when document becomes visible', () => {
+    it('should NOT force flush spans', () => {
+      assert.strictEqual(forceFlushSpy.callCount, 0);
+      document.dispatchEvent(visibilityChangeEvent);
+      assert.strictEqual(forceFlushSpy.callCount, 0);
+    });
+  })
+});

packages/opentelemetry-tracing/test/index-webpack.ts → packages/opentelemetry-tracing/test/browser/index-webpack.ts

@@ -13,8 +13,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-const testsContext = require.context('.', true, /test$/);
+const testsContext = require.context('../browser', true, /test$/);
 testsContext.keys().forEach(testsContext);
 
+const testsContextCommon = require.context('../common', true, /test$/);
+testsContextCommon.keys().forEach(testsContextCommon);
+
 const srcContext = require.context('.', true, /src$/);
 srcContext.keys().forEach(srcContext);

packages/opentelemetry-tracing/test/BasicTracerProvider.test.ts → packages/opentelemetry-tracing/test/common/BasicTracerProvider.test.ts

@@ -43,7 +43,7 @@ import {
   InMemorySpanExporter,
   SpanExporter,
   BatchSpanProcessor,
-} from '../src';
+} from '../../src';
 
 describe('BasicTracerProvider', () => {
   let removeEvent: Function | undefined;

packages/opentelemetry-tracing/test/MultiSpanProcessor.test.ts → packages/opentelemetry-tracing/test/common/MultiSpanProcessor.test.ts

@@ -22,12 +22,12 @@ import {
   SimpleSpanProcessor,
   Span,
   SpanProcessor,
-} from '../src';
+} from '../../src';
 import {
   setGlobalErrorHandler,
   loggingErrorHandler,
 } from '@opentelemetry/core';
-import { MultiSpanProcessor } from '../src/MultiSpanProcessor';
+import { MultiSpanProcessor } from '../../src/MultiSpanProcessor';
 
 class TestProcessor implements SpanProcessor {
   spans: Span[] = [];

packages/opentelemetry-tracing/test/Span.test.ts → packages/opentelemetry-tracing/test/common/Span.test.ts

@@ -30,7 +30,7 @@ import {
 } from '@opentelemetry/core';
 import { SemanticAttributes } from '@opentelemetry/semantic-conventions';
 import * as assert from 'assert';
-import { BasicTracerProvider, Span, SpanProcessor } from '../src';
+import { BasicTracerProvider, Span, SpanProcessor } from '../../src';
 
 const performanceTimeOrigin = hrTime();
 

packages/opentelemetry-tracing/test/Tracer.test.ts → packages/opentelemetry-tracing/test/common/Tracer.test.ts

@@ -30,7 +30,7 @@ import {
   suppressTracing,
 } from '@opentelemetry/core';
 import * as assert from 'assert';
-import { BasicTracerProvider, Span, Tracer } from '../src';
+import { BasicTracerProvider, Span, Tracer } from '../../src';
 
 describe('Tracer', () => {
   const tracerProvider = new BasicTracerProvider();

packages/opentelemetry-tracing/test/config.test.ts → packages/opentelemetry-tracing/test/common/config.test.ts

@@ -20,7 +20,7 @@ import {
   TraceIdRatioBasedSampler,
 } from '@opentelemetry/core';
 import * as assert from 'assert';
-import { buildSamplerFromEnv } from '../src/config';
+import { buildSamplerFromEnv } from '../../src/config';
 
 describe('config', () => {
   const envSource = (typeof window !== 'undefined'