feat(core): add stringToLogLevel utility

CHANGELOG.md

@@ -110,6 +110,7 @@ For semantic convention package changes, see the [semconv CHANGELOG](packages/se
 * feat(sdk-trace-base): add stack trace warning to debug instrumentation [#5363](https://github.com/open-telemetry/opentelemetry-js/pull/5363) @neilfordyce
 * feat(core): add more scalable replacements for getEnv(), getEnvWithoutDefaults() [#5443](https://github.com/open-telemetry/opentelemetry-js/pull/5443) @pichlermarc
 * refactor(exporter-jaeger): migrate away from getEnv() [#5464](https://github.com/open-telemetry/opentelemetry-js/pull/5464) @pichlermarc
+* feat(core): add stringToLogLevel utility [#5475](https://github.com/open-telemetry/opentelemetry-js/pull/5475) @pichlermarc
 
 ### :bug: (Bug Fix)
 

experimental/CHANGELOG.md

@@ -39,6 +39,7 @@ All notable changes to experimental packages in this project will be documented
 * refactor(exporter-prometheus): remove unnecessary isNaN() check [#5377](https://github.com/open-telemetry/opentelemetry-js/pull/5377) @cjihrig
 * refactor(sdk-node): move code to auto-instantiate propagators into utils [#5355](https://github.com/open-telemetry/opentelemetry-js/pull/5355) @pichlermarc
 * chore: unpin `@opentelemetry/semantic-conventions` dep to allow better de-duplication in installs [#5439](https://github.com/open-telemetry/opentelemetry-js/pull/5439) @trentm
+* refactor(sdk-node): migrate away from getEnv() [#5475](https://github.com/open-telemetry/opentelemetry-js/pull/5475) @pichlermarc
 
 ## 0.57.0
 

packages/opentelemetry-core/src/index.ts

@@ -88,6 +88,7 @@ export { merge } from './utils/merge';
 export { TimeoutError, callWithTimeout } from './utils/timeout';
 export { isUrlIgnored, urlMatches } from './utils/url';
 export { BindOnceFuture } from './utils/callback';
+export { stringToLogLevel } from './utils/configuration';
 import { _export } from './internal/exporter';
 export const internal = {
   _export,

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

@@ -0,0 +1,51 @@
+/*
+ * 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 { diag, DiagLogLevel } from '@opentelemetry/api';
+import { inspect } from 'util';
+
+const logLevelMap: { [key: string]: DiagLogLevel } = {
+  ALL: DiagLogLevel.ALL,
+  VERBOSE: DiagLogLevel.VERBOSE,
+  DEBUG: DiagLogLevel.DEBUG,
+  INFO: DiagLogLevel.INFO,
+  WARN: DiagLogLevel.WARN,
+  ERROR: DiagLogLevel.ERROR,
+  NONE: DiagLogLevel.NONE,
+};
+
+/**
+ * Convert a string to a {@link DiagLogLevel}, defaults to {@link DiagLogLevel} if the log level does not exist or undefined if the input is undefined.
+ * @param value
+ */
+export function stringToLogLevel(
+  value: string | undefined
+): DiagLogLevel | undefined {
+  if (value == null) {
+    // don't fall back to default - no value set has different semantics for ús than an incorrect value (do not set vs. fall back to default)
+    return undefined;
+  }
+
+  const resolvedLogLevel = logLevelMap[value.toUpperCase()];
+
+  if (resolvedLogLevel == null) {
+    diag.warn(
+      `Unknown log level ${inspect(value)}, expected one of ${inspect(Object.keys(logLevelMap))}, using default`
+    );
+    return DiagLogLevel.INFO;
+  }
+
+  return resolvedLogLevel;
+}

packages/opentelemetry-core/test/common/utils/configuration.ts

@@ -0,0 +1,54 @@
+/*
+ * 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 { stringToLogLevel } from '../../../src';
+import * as assert from 'assert';
+import * as sinon from 'sinon';
+import { diag, DiagLogLevel } from '@opentelemetry/api';
+
+describe('stringToLogLevel', function () {
+  afterEach(function () {
+    sinon.restore();
+  });
+
+  it('should map valid string to log level', function () {
+    assert.strictEqual(stringToLogLevel('ALL'), DiagLogLevel.ALL);
+    assert.strictEqual(stringToLogLevel('VERBOSE'), DiagLogLevel.VERBOSE);
+    assert.strictEqual(stringToLogLevel('DEBUG'), DiagLogLevel.DEBUG);
+    assert.strictEqual(stringToLogLevel('INFO'), DiagLogLevel.INFO);
+    assert.strictEqual(stringToLogLevel('WARN'), DiagLogLevel.WARN);
+    assert.strictEqual(stringToLogLevel('ERROR'), DiagLogLevel.ERROR);
+    assert.strictEqual(stringToLogLevel('NONE'), DiagLogLevel.NONE);
+  });
+
+  it('should ignore casing when resolving', function () {
+    assert.strictEqual(stringToLogLevel('error'), DiagLogLevel.ERROR);
+    assert.strictEqual(stringToLogLevel('eRRoR'), DiagLogLevel.ERROR);
+  });
+
+  it('should return undefined on undefined input', function () {
+    assert.strictEqual(stringToLogLevel(undefined), undefined);
+  });
+
+  it('should return undefined on null input', function () {
+    assert.strictEqual(stringToLogLevel(undefined), undefined);
+  });
+
+  it('should fall back to INFO and warn on input that cannot be mapped', function () {
+    const warnStub = sinon.stub(diag, 'warn');
+    assert.strictEqual(stringToLogLevel('does not exist'), DiagLogLevel.INFO);
+    sinon.assert.calledOnceWithMatch(warnStub, 'Unknown');
+  });
+});