feat(sdk-node): always set up propagation and context manager

experimental/CHANGELOG.md

@@ -10,6 +10,9 @@ For notes on migrating to 2.x / 0.200.x see [the upgrade guide](doc/upgrade-to-2
 
 ### :rocket: Features
 
+* feat(sdk-node): always set up propagtion and context manager [#5930](https://github.com/open-telemetry/opentelemetry-js/pull/5930)
+  * using `(new NodeSDK).start()` will now automatically set up a context management and propagation, even if no Trace SDK
+    is initialized.
 * feat(otlp-exporter-base, otlp-grpc-exporter-base): add an option to let an SDK distribution prepend their own user-agent string in HTTP & GRPC exporters [#5928](https://github.com/open-telemetry/opentelemetry-js/pull/5928) @david-luna
 
 ### :bug: Bug Fixes

experimental/packages/opentelemetry-sdk-node/src/sdk.ts

@@ -14,13 +14,7 @@
  * limitations under the License.
  */
 
-import {
-  ContextManager,
-  TextMapPropagator,
-  metrics,
-  diag,
-  DiagConsoleLogger,
-} from '@opentelemetry/api';
+import { metrics, trace, diag, DiagConsoleLogger } from '@opentelemetry/api';
 import { logs } from '@opentelemetry/api-logs';
 import {
   Instrumentation,
@@ -79,9 +73,14 @@ import {
   getResourceDetectorsFromEnv,
   getSpanProcessorsFromEnv,
   getPropagatorFromEnv,
+  setupPropagator,
+  setupContextManager,
 } from './utils';
 
-/** This class represents everything needed to register a fully configured OpenTelemetry Node.js SDK */
+type TracerProviderConfig = {
+  tracerConfig: NodeTracerConfig;
+  spanProcessors: SpanProcessor[];
+};
 
 export type MeterProviderConfig = {
   /**
@@ -129,6 +128,7 @@ function configureMetricProviderFromEnv(): IMetricReader[] {
     );
     return metricReaders;
   }
+
   enabledExporters.forEach(exporter => {
     if (exporter === 'otlp') {
       const protocol =
@@ -201,13 +201,27 @@ function configureMetricProviderFromEnv(): IMetricReader[] {
 
   return metricReaders;
 }
+
+/**
+ * A setup helper for the OpenTelemetry SDKs (logs, metrics, traces).
+ * <p> After successful setup using {@link NodeSDK#start()}, use `@opentelemetry/api` to obtain the registered components.
+ * <p> Use the shutdown handler {@link NodeSDK#shutdown()} to ensure your telemetry is exported before the process exits.
+ *
+ * @example <caption> Register SDK by using environment variables </caption>
+ *    const nodeSdk = new NodeSDK(); // providing no options uses OTEL_* environment variables for SDK setup.
+ *    nodeSdk.start(); // registers all configured SDK components
+ * @example <caption> Override environment variable config with your own components </caption>
+ *    const nodeSdk = new NodeSDK({
+ *      // override the list of metric reader with your own options and ignore environment variable config
+ *      // explore the docs of other options to learn more!
+ *      metricReaders: [ new PeriodicExportingMetricReader({
+ *        exporter: new OTLPMetricsExporter()
+ *        })]
+ *    });
+ *    nodeSdk.start(); // registers all configured SDK components
+ */
 export class NodeSDK {
-  private _tracerProviderConfig?: {
-    tracerConfig: NodeTracerConfig;
-    spanProcessors: SpanProcessor[];
-    contextManager?: ContextManager;
-    textMapPropagator?: TextMapPropagator;
-  };
+  private _tracerProviderConfig?: TracerProviderConfig;
   private _loggerProviderConfig?: LoggerProviderConfig;
   private _meterProviderConfig?: MeterProviderConfig;
   private _instrumentations: Instrumentation[];
@@ -292,8 +306,6 @@ export class NodeSDK {
       this._tracerProviderConfig = {
         tracerConfig: tracerProviderConfig,
         spanProcessors,
-        contextManager: configuration.contextManager,
-        textMapPropagator: configuration.textMapPropagator,
       };
     }
 
@@ -350,6 +362,13 @@ export class NodeSDK {
       instrumentations: this._instrumentations,
     });
 
+    setupContextManager(this._configuration?.contextManager);
+    setupPropagator(
+      this._configuration?.textMapPropagator === null
+        ? null // null means don't set, so we cannot fall back to env config.
+        : (this._configuration?.textMapPropagator ?? getPropagatorFromEnv())
+    );
+
     if (this._autoDetectResources) {
       const internalConfig: ResourceDetectionConfig = {
         detectors: this._resourceDetectors,
@@ -371,23 +390,14 @@ export class NodeSDK {
       ? this._tracerProviderConfig.spanProcessors
       : getSpanProcessorsFromEnv();
 
-    this._tracerProvider = new NodeTracerProvider({
-      ...this._configuration,
-      resource: this._resource,
-      spanProcessors,
-    });
-
     // Only register if there is a span processor
     if (spanProcessors.length > 0) {
-      this._tracerProvider.register({
-        contextManager:
-          this._tracerProviderConfig?.contextManager ??
-          // _tracerProviderConfig may be undefined if trace-specific settings are not provided - fall back to raw config
-          this._configuration?.contextManager,
-        propagator:
-          this._tracerProviderConfig?.textMapPropagator ??
-          getPropagatorFromEnv(),
+      this._tracerProvider = new NodeTracerProvider({
+        ...this._configuration,
+        resource: this._resource,
+        spanProcessors,
       });
+      trace.setGlobalTracerProvider(this._tracerProvider);
     }
 
     if (this._loggerProviderConfig) {

experimental/packages/opentelemetry-sdk-node/src/types.ts

@@ -31,7 +31,7 @@ import {
 export interface NodeSDKConfiguration {
   autoDetectResources: boolean;
   contextManager: ContextManager;
-  textMapPropagator: TextMapPropagator;
+  textMapPropagator: TextMapPropagator | null;
   /** @deprecated use logRecordProcessors instead*/
   logRecordProcessor: LogRecordProcessor;
   logRecordProcessors?: LogRecordProcessor[];

experimental/packages/opentelemetry-sdk-node/src/utils.ts

@@ -14,7 +14,13 @@
  * limitations under the License.
  */
 
-import { diag, TextMapPropagator } from '@opentelemetry/api';
+import {
+  context,
+  ContextManager,
+  diag,
+  propagation,
+  TextMapPropagator,
+} from '@opentelemetry/api';
 import {
   CompositePropagator,
   getStringFromEnv,
@@ -43,6 +49,7 @@ import {
 } from '@opentelemetry/sdk-trace-base';
 import { B3InjectEncoding, B3Propagator } from '@opentelemetry/propagator-b3';
 import { JaegerPropagator } from '@opentelemetry/propagator-jaeger';
+import { AsyncLocalStorageContextManager } from '@opentelemetry/context-async-hooks';
 
 const RESOURCE_DETECTOR_ENVIRONMENT = 'env';
 const RESOURCE_DETECTOR_HOST = 'host';
@@ -198,6 +205,10 @@ export function getPropagatorFromEnv(): TextMapPropagator | null | undefined {
     return undefined;
   }
 
+  if (propagatorsEnvVarValue.includes('none')) {
+    return null;
+  }
+
   // Implementation note: this only contains specification required propagators that are actually hosted in this repo.
   // Any other propagators (like aws, aws-lambda, should go into `@opentelemetry/auto-configuration-propagators` instead).
   const propagatorsFactory = new Map<string, () => TextMapPropagator>([
@@ -247,3 +258,47 @@ export function getPropagatorFromEnv(): TextMapPropagator | null | undefined {
     });
   }
 }
+
+export function setupContextManager(
+  contextManager: ContextManager | null | undefined
+) {
+  // null means 'do not register'
+  if (contextManager === null) {
+    return;
+  }
+
+  // undefined means 'register default'
+  if (contextManager === undefined) {
+    const defaultContextManager = new AsyncLocalStorageContextManager();
+    defaultContextManager.enable();
+    context.setGlobalContextManager(defaultContextManager);
+    return;
+  }
+
+  contextManager.enable();
+  context.setGlobalContextManager(contextManager);
+}
+
+export function setupPropagator(
+  propagator: TextMapPropagator | null | undefined
+) {
+  // null means 'do not register'
+  if (propagator === null) {
+    return;
+  }
+
+  // undefined means 'register default'
+  if (propagator === undefined) {
+    propagation.setGlobalPropagator(
+      new CompositePropagator({
+        propagators: [
+          new W3CTraceContextPropagator(),
+          new W3CBaggagePropagator(),
+        ],
+      })
+    );
+    return;
+  }
+
+  propagation.setGlobalPropagator(propagator);
+}