Add multi-instance SDK support via delegating providers

CHANGELOG.md

@@ -11,6 +11,9 @@
 - Bump `@azure/monitor-opentelemetry-exporter` floor to `1.0.0-beta.43`
 - Bump `@opentelemetry/*` core/SDK packages to `2.8.0` / `0.219.0`
 
+### Features Added
+- Support multiple isolated SDK instances, each with its own instrumentations, settings, and exporter (e.g. different instrumentations for Azure Monitor vs. A365)
+
 ## [1.1.0] - 2026-05-29
 
 ### Features Added

package.json

@@ -87,6 +87,7 @@
     "@microsoft/applicationinsights-web-snippet": "^1.2.3",
     "@opentelemetry/api": "^1.9.0",
     "@opentelemetry/api-logs": "^0.219.0",
+    "@opentelemetry/context-async-hooks": "^2.8.0",
     "@opentelemetry/core": "^2.8.0",
     "@opentelemetry/exporter-logs-otlp-http": "^0.219.0",
     "@opentelemetry/exporter-metrics-otlp-http": "^0.219.0",

src/distro/distro.ts

@@ -53,85 +53,19 @@ import {
   SdkStatsFeature,
 } from "../types.js";
 import { createInstrumentations, createSampler, createViews } from "./instrumentations.js";
+import { _applyA365InstrumentationDefaults } from "./instrumentations.js";
 import { Logger } from "../shared/logging/index.js";
 
+// Re-export to preserve the existing import path used by tests/consumers.
+export { _applyA365InstrumentationDefaults };
+
 process.env["AZURE_MONITOR_DISTRO_VERSION"] = AZURE_MONITOR_OPENTELEMETRY_VERSION;
 process.env["MICROSOFT_OPENTELEMETRY_VERSION"] = MICROSOFT_OPENTELEMETRY_VERSION;
 
 let sdk: NodeSDK;
 let disposeAzureMonitor: (() => void) | undefined;
 let isShutdown = false;
 
-const A365_DISABLED_INSTRUMENTATIONS_BY_DEFAULT: ReadonlyArray<keyof InstrumentationOptions> = [
-  "http",
-  "azureSdk",
-  "mongoDb",
-  "mySql",
-  "postgreSql",
-  "redis",
-  "redis4",
-  "bunyan",
-  "winston",
-];
-
-/**
- * Redis and redis4 share the same underlying instrumentation. If a caller
- * explicitly configures either key, treat both as explicitly configured so
- * the other is not inadvertently disabled.
- */
-const REDIS_LINKED_KEYS: ReadonlyArray<keyof InstrumentationOptions> = ["redis", "redis4"];
-
-/**
- * When A365 export is enabled, default to GenAI-focused telemetry by disabling
- * non-GenAI instrumentations unless callers explicitly configure them.
- *
- * @internal
- */
-export function _applyA365InstrumentationDefaults(
-  instrumentationOptions: InstrumentationOptions,
-  userInstrumentationOptions: unknown,
-  a365Enabled: boolean,
-): void {
-  if (!a365Enabled) {
-    return;
-  }
-
-  const userOptionsRecord =
-    userInstrumentationOptions && typeof userInstrumentationOptions === "object"
-      ? (userInstrumentationOptions as Record<string, unknown>)
-      : undefined;
-
-  // Pre-compute whether any Redis-linked key was explicitly configured so
-  // that configuring `redis4` alone does not inadvertently disable `redis`
-  // (and vice-versa), which would break the underlying shared instrumentation.
-  const redisLinkedExplicit =
-    !!userOptionsRecord &&
-    REDIS_LINKED_KEYS.some((k) => Object.prototype.hasOwnProperty.call(userOptionsRecord, k));
-
-  for (const instrumentationKey of A365_DISABLED_INSTRUMENTATIONS_BY_DEFAULT) {
-    const isExplicitlyConfigured =
-      !!userOptionsRecord &&
-      Object.prototype.hasOwnProperty.call(userOptionsRecord, instrumentationKey);
-
-    // Treat redis/redis4 as a linked pair: if either was set by the caller,
-    // skip disabling both keys.
-    if (
-      isExplicitlyConfigured ||
-      (redisLinkedExplicit &&
-        REDIS_LINKED_KEYS.includes(instrumentationKey as (typeof REDIS_LINKED_KEYS)[number]))
-    ) {
-      continue;
-    }
-
-    const currentValue = instrumentationOptions[instrumentationKey];
-    if (currentValue && typeof currentValue === "object") {
-      (currentValue as Record<string, unknown>).enabled = false;
-    } else {
-      instrumentationOptions[instrumentationKey] = { enabled: false };
-    }
-  }
-}
-
 /**
  * Initialize Microsoft OpenTelemetry.
  *

src/distro/index.ts

@@ -7,6 +7,11 @@ export type {
   BrowserSdkLoaderOptions,
   A365Options,
 } from "./types.js";
+export type { MicrosoftOpenTelemetryInstance } from "../types.js";
 export { MICROSOFT_OPENTELEMETRY_VERSION } from "./types.js";
 
 export { useMicrosoftOpenTelemetry, shutdownMicrosoftOpenTelemetry } from "./distro.js";
+export {
+  createMicrosoftOpenTelemetryInstance,
+  runWithMicrosoftOpenTelemetryInstance,
+} from "./multiInstance/index.js";

src/distro/instrumentations.ts

@@ -26,10 +26,83 @@ import type { Instrumentation } from "@opentelemetry/instrumentation";
 import type { ViewOptions } from "@opentelemetry/sdk-metrics";
 
 import type { InternalConfig } from "../shared/config.js";
+import type { InstrumentationOptions } from "../types.js";
 import { ignoreOutgoingRequestHook } from "../azureMonitor/utils/common.js";
 import { ApplicationInsightsSampler } from "../azureMonitor/traces/sampler.js";
 import { logLevelToSeverityNumber } from "../azureMonitor/utils/logUtils.js";
 
+// ── A365 instrumentation defaults ───────────────────────────────────
+
+const A365_DISABLED_INSTRUMENTATIONS_BY_DEFAULT: ReadonlyArray<keyof InstrumentationOptions> = [
+  "http",
+  "azureSdk",
+  "mongoDb",
+  "mySql",
+  "postgreSql",
+  "redis",
+  "redis4",
+  "bunyan",
+  "winston",
+];
+
+/**
+ * Redis and redis4 share the same underlying instrumentation. If a caller
+ * explicitly configures either key, treat both as explicitly configured so
+ * the other is not inadvertently disabled.
+ */
+const REDIS_LINKED_KEYS: ReadonlyArray<keyof InstrumentationOptions> = ["redis", "redis4"];
+
+/**
+ * When A365 export is enabled, default to GenAI-focused telemetry by disabling
+ * non-GenAI instrumentations unless callers explicitly configure them.
+ *
+ * @internal
+ */
+export function _applyA365InstrumentationDefaults(
+  instrumentationOptions: InstrumentationOptions,
+  userInstrumentationOptions: unknown,
+  a365Enabled: boolean,
+): void {
+  if (!a365Enabled) {
+    return;
+  }
+
+  const userOptionsRecord =
+    userInstrumentationOptions && typeof userInstrumentationOptions === "object"
+      ? (userInstrumentationOptions as Record<string, unknown>)
+      : undefined;
+
+  // Pre-compute whether any Redis-linked key was explicitly configured so
+  // that configuring `redis4` alone does not inadvertently disable `redis`
+  // (and vice-versa), which would break the underlying shared instrumentation.
+  const redisLinkedExplicit =
+    !!userOptionsRecord &&
+    REDIS_LINKED_KEYS.some((k) => Object.prototype.hasOwnProperty.call(userOptionsRecord, k));
+
+  for (const instrumentationKey of A365_DISABLED_INSTRUMENTATIONS_BY_DEFAULT) {
+    const isExplicitlyConfigured =
+      !!userOptionsRecord &&
+      Object.prototype.hasOwnProperty.call(userOptionsRecord, instrumentationKey);
+
+    // Treat redis/redis4 as a linked pair: if either was set by the caller,
+    // skip disabling both keys.
+    if (
+      isExplicitlyConfigured ||
+      (redisLinkedExplicit &&
+        REDIS_LINKED_KEYS.includes(instrumentationKey as (typeof REDIS_LINKED_KEYS)[number]))
+    ) {
+      continue;
+    }
+
+    const currentValue = instrumentationOptions[instrumentationKey];
+    if (currentValue && typeof currentValue === "object") {
+      (currentValue as Record<string, unknown>).enabled = false;
+    } else {
+      instrumentationOptions[instrumentationKey] = { enabled: false };
+    }
+  }
+}
+
 // ── Instrumentations ────────────────────────────────────────────────
 
 /**