Add platform agnostic way to read environment variables

packages/opentelemetry-api/src/index.ts

@@ -30,6 +30,7 @@ export * from './metrics/MetricObservable';
 export * from './metrics/NoopMeter';
 export * from './metrics/NoopMeterProvider';
 export * from './metrics/ObserverResult';
+export * from './platform';
 export * from './trace/attributes';
 export * from './trace/Event';
 export * from './trace/instrumentation/Plugin';

packages/opentelemetry-core/src/platform/browser/environment.ts

@@ -0,0 +1,33 @@
+/*
+ * 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 {
+ DEFAULT_ENVIRONMENT,
+ ENVIRONMENT,
+ ENVIRONMENT_MAP,
+ parseEnvironment,
+} from '../../utils/environment';
+import * as api from '@opentelemetry/api';
+
+/**
+ * Gets the environment variables
+ */
+export function getEnv(): ENVIRONMENT {
+ const globalEnv = parseEnvironment(
+ (api._globalThis as unknown) as ENVIRONMENT_MAP
+ );
+ return Object.assign({}, DEFAULT_ENVIRONMENT, globalEnv);
+}

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

@@ -15,6 +15,7 @@
  */
 
 export * from './BasePlugin';
+export * from './environment';
 export * from './hex-to-base64';
 export * from './id';
 export * from './performance';

packages/opentelemetry-core/src/platform/node/environment.ts

@@ -0,0 +1,30 @@
+/*
+ * 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 {
+ DEFAULT_ENVIRONMENT,
+ ENVIRONMENT,
+ ENVIRONMENT_MAP,
+ parseEnvironment,
+} from '../../utils/environment';
+
+/**
+ * Gets the environment variables
+ */
+export function getEnv(): ENVIRONMENT {
+ const processEnv = parseEnvironment(process.env as ENVIRONMENT_MAP);
+ return Object.assign({}, DEFAULT_ENVIRONMENT, processEnv);
+}

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

@@ -15,8 +15,9 @@
  */
 
 export * from './BasePlugin';
+export * from './environment';
+export * from './hex-to-base64';
 export * from './id';
 export * from './performance';
 export * from './sdk-info';
 export * from './timer-util';
-export * from './hex-to-base64';

packages/opentelemetry-core/src/utils/environment.ts

@@ -0,0 +1,97 @@
+/*
+ * 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 { LogLevel } from '../common/types';
+
+export type ENVIRONMENT_MAP = { [key: string]: string | number };
+
+/**
+ * Environment interface to define all names
+ */
+export interface ENVIRONMENT {
+ OTEL_LOG_LEVEL?: LogLevel;
+ OTEL_NO_PATCH_MODULES?: string;
+ OTEL_SAMPLING_PROBABILITY?: number;
+}
+
+const ENVIRONMENT_NUMBERS: Partial<keyof ENVIRONMENT>[] = [
+ 'OTEL_LOG_LEVEL',
+ 'OTEL_SAMPLING_PROBABILITY',
+];
+
+/**
+ * Default environment variables
+ */
+export const DEFAULT_ENVIRONMENT: ENVIRONMENT = {
+ OTEL_NO_PATCH_MODULES: '',
+ OTEL_LOG_LEVEL: LogLevel.ERROR,
+ OTEL_SAMPLING_PROBABILITY: 1,
+};
+
+/**
+ * Parses a variable as number with number validation
+ * @param name
+ * @param environment
+ * @param values
+ * @param min
+ * @param max
+ */
+function parseNumber(
+ name: keyof ENVIRONMENT,
+ environment: ENVIRONMENT_MAP | ENVIRONMENT,
+ values: ENVIRONMENT_MAP,
+ min = -Infinity,
+ max = Infinity
+) {
+ if (typeof values[name] !== 'undefined') {
+ const value = Number(values[name] as string);
+ if (!isNaN(value) && value >= min && value <= max) {
+ environment[name] = value;
+ }
+ }
+}
+
+/**
+ * Parses environment values
+ * @param values
+ */
+export function parseEnvironment(values: ENVIRONMENT_MAP): ENVIRONMENT {
+ const environment: ENVIRONMENT_MAP = {};
+
+ for (const env in DEFAULT_ENVIRONMENT) {
+ const key = env as keyof ENVIRONMENT;
+ switch (key) {
+ case 'OTEL_SAMPLING_PROBABILITY':
+ parseNumber(key, environment, values, 0, 1);
+ break;
+
+ case 'OTEL_LOG_LEVEL':
+ parseNumber(key, environment, values, LogLevel.ERROR, LogLevel.DEBUG);
+ break;
+
+ default:
+ if (ENVIRONMENT_NUMBERS.indexOf(key) >= 0) {
+ parseNumber(key, environment, values);
+ } else {
+ if (typeof values[key] !== 'undefined') {
+ environment[key] = values[key];
+ }
+ }
+ }
+ }
+
+ return environment;
+}

packages/opentelemetry-core/test/utils/environment.test.ts

@@ -0,0 +1,92 @@
+/*
+ * 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 { getEnv } from '../../src/platform';
+import {
+ DEFAULT_ENVIRONMENT,
+ ENVIRONMENT,
+ ENVIRONMENT_MAP,
+} from '../../src/utils/environment';
+import * as assert from 'assert';
+import * as sinon from 'sinon';
+
+let lastMock: ENVIRONMENT_MAP = {};
+
+function mockEnvironment(values: ENVIRONMENT_MAP) {
+ lastMock = values;
+ if (typeof process !== 'undefined') {
+ Object.keys(values).forEach(key => {
+ process.env[key] = String(values[key]);
+ });
+ } else {
+ Object.keys(values).forEach(key => {
+ ((window as unknown) as ENVIRONMENT_MAP)[key] = String(values[key]);
+ });
+ }
+}
+
+function removeMockEnvironment() {
+ if (typeof process !== 'undefined') {
+ Object.keys(lastMock).forEach(key => {
+ delete process.env[key];
+ });
+ } else {
+ Object.keys(lastMock).forEach(key => {
+ delete ((window as unknown) as ENVIRONMENT_MAP)[key];
+ });
+ }
+ lastMock = {};
+}
+
+describe('environment', () => {
+ let sandbox: sinon.SinonSandbox;
+
+ beforeEach(() => {
+ sandbox = sinon.createSandbox();
+ });
+
+ afterEach(() => {
+ removeMockEnvironment();
+ sandbox.restore();
+ });
+
+ describe('parseEnvironment', () => {
+ it('should parse environment variables', () => {
+ mockEnvironment({
+ FOO: '1',
+ OTEL_NO_PATCH_MODULES: 'a,b,c',
+ OTEL_LOG_LEVEL: '1',
+ OTEL_SAMPLING_PROBABILITY: '0.5',
+ });
+ const env = getEnv();
+ assert.strictEqual(env.OTEL_NO_PATCH_MODULES, 'a,b,c');
+ assert.strictEqual(env.OTEL_LOG_LEVEL, 1);
+ assert.strictEqual(env.OTEL_SAMPLING_PROBABILITY, 0.5);
+ });
+
+ it('should parse environment variables and use defaults', () => {
+ const env = getEnv();
+ Object.keys(DEFAULT_ENVIRONMENT).forEach(envKey => {
+ const key = envKey as keyof ENVIRONMENT;
+ assert.strictEqual(
+ env[key as keyof ENVIRONMENT],
+ DEFAULT_ENVIRONMENT[key],
+ `Variable '${key}' doesn't match`
+ );
+ });
+ });
+ });
+});