Refactor to remove circular dep

langchain-core/src/callbacks/manager.ts

@@ -1273,10 +1273,10 @@ export class CallbackManager
         handler = contextVarValue;
       } else if (createIfNotInContext) {
         // eslint-disable-next-line @typescript-eslint/no-explicit-any
-        handler = new (handlerClass as any)();
+        handler = new (handlerClass as any)({});
       }
       if (handler !== undefined) {
-        if (!callbackManager?.handlers.some((h) => h.name === handler.name)) {
+        if (!callbackManager?.handlers.some((h) => h.name === handler!.name)) {
           callbackManager?.addHandler(handler, inheritable);
         }
       }

langchain-core/src/singletons/async_local_storage/context.ts

@@ -1,9 +1,9 @@
 import { isRunTree, RunTree } from "langsmith/run_trees";
+import { BaseCallbackHandler } from "../../callbacks/base.js";
 import {
   _CONTEXT_VARIABLES_KEY,
-  AsyncLocalStorageProviderSingleton,
-} from "./index.js";
-import { BaseCallbackHandler } from "../../callbacks/base.js";
+  getGlobalAsyncLocalStorageInstance,
+} from "./globals.js";
 
 /**
  * Set a context variable. Context variables are scoped to any
@@ -57,7 +57,14 @@ import { BaseCallbackHandler } from "../../callbacks/base.js";
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export function setContextVariable<T>(name: PropertyKey, value: T): void {
-  const runTree = AsyncLocalStorageProviderSingleton.getInstance().getStore();
+  // Avoid using global singleton due to circuluar dependency issues
+  const asyncLocalStorageInstance = getGlobalAsyncLocalStorageInstance();
+  if (asyncLocalStorageInstance === undefined) {
+    throw new Error(
+      `Internal error: Global shared async local storage instance has not been initialized.`
+    );
+  }
+  const runTree = asyncLocalStorageInstance.getStore();
   const contextVars = { ...runTree?.[_CONTEXT_VARIABLES_KEY] };
   contextVars[name] = value;
   let newValue = {};
@@ -66,7 +73,7 @@ export function setContextVariable<T>(name: PropertyKey, value: T): void {
   }
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   (newValue as any)[_CONTEXT_VARIABLES_KEY] = contextVars;
-  AsyncLocalStorageProviderSingleton.getInstance().enterWith(newValue);
+  asyncLocalStorageInstance.enterWith(newValue);
 }
 
 /**
@@ -120,7 +127,12 @@ export function setContextVariable<T>(name: PropertyKey, value: T): void {
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export function getContextVariable<T = any>(name: PropertyKey): T | undefined {
-  const runTree = AsyncLocalStorageProviderSingleton.getInstance().getStore();
+  // Avoid using global singleton due to circuluar dependency issues
+  const asyncLocalStorageInstance = getGlobalAsyncLocalStorageInstance();
+  if (asyncLocalStorageInstance === undefined) {
+    return undefined;
+  }
+  const runTree = asyncLocalStorageInstance.getStore();
   return runTree?.[_CONTEXT_VARIABLES_KEY]?.[name];
 }
 

langchain-core/src/singletons/async_local_storage/globals.ts

@@ -9,12 +9,16 @@ export interface AsyncLocalStorageInterface {
 
 export const TRACING_ALS_KEY = Symbol.for("ls:tracing_async_local_storage");
 
+export const _CONTEXT_VARIABLES_KEY = Symbol.for("lc:context_variables");
+
 export const setGlobalAsyncLocalStorageInstance = (
   instance: AsyncLocalStorageInterface
 ) => {
   (globalThis as any)[TRACING_ALS_KEY] = instance;
 };
 
-export const getGlobalAsyncLocalStorageInstance = () => {
+export const getGlobalAsyncLocalStorageInstance = ():
+  | AsyncLocalStorageInterface
+  | undefined => {
   return (globalThis as any)[TRACING_ALS_KEY];
 };

langchain-core/src/singletons/async_local_storage/index.ts

@@ -4,6 +4,7 @@ import {
   AsyncLocalStorageInterface,
   getGlobalAsyncLocalStorageInstance,
   setGlobalAsyncLocalStorageInstance,
+  _CONTEXT_VARIABLES_KEY,
 } from "./globals.js";
 import { CallbackManager } from "../../callbacks/manager.js";
 import { LangChainTracer } from "../../tracers/tracer_langchain.js";
@@ -26,8 +27,6 @@ const mockAsyncLocalStorage = new MockAsyncLocalStorage();
 
 const LC_CHILD_KEY = Symbol.for("lc:child_config");
 
-export const _CONTEXT_VARIABLES_KEY = Symbol.for("lc:context_variables");
-
 class AsyncLocalStorageProvider {
   getInstance(): AsyncLocalStorageInterface {
     return getGlobalAsyncLocalStorageInstance() ?? mockAsyncLocalStorage;

langchain-core/src/singletons/callbacks.ts

@@ -37,20 +37,18 @@ export async function consumeCallback<T>(
   if (wait === true) {
     // Clear config since callbacks are not part of the root run
     // Avoid using global singleton due to circuluar dependency issues
-    if (getGlobalAsyncLocalStorageInstance() !== undefined) {
-      await getGlobalAsyncLocalStorageInstance().run(undefined, async () =>
-        promiseFn()
-      );
+    const asyncLocalStorageInstance = getGlobalAsyncLocalStorageInstance();
+    if (asyncLocalStorageInstance !== undefined) {
+      await asyncLocalStorageInstance.run(undefined, async () => promiseFn());
     } else {
       await promiseFn();
     }
   } else {
     queue = getQueue();
     void queue.add(async () => {
-      if (getGlobalAsyncLocalStorageInstance() !== undefined) {
-        await getGlobalAsyncLocalStorageInstance().run(undefined, async () =>
-          promiseFn()
-        );
+      const asyncLocalStorageInstance = getGlobalAsyncLocalStorageInstance();
+      if (asyncLocalStorageInstance !== undefined) {
+        await asyncLocalStorageInstance.run(undefined, async () => promiseFn());
       } else {
         await promiseFn();
       }

langchain-core/src/singletons/index.ts

@@ -2,13 +2,11 @@
 import {
   type AsyncLocalStorageInterface,
   AsyncLocalStorageProviderSingleton,
-  _CONTEXT_VARIABLES_KEY,
   MockAsyncLocalStorage,
 } from "./async_local_storage/index.js";
 
 export {
   type AsyncLocalStorageInterface,
   AsyncLocalStorageProviderSingleton,
-  _CONTEXT_VARIABLES_KEY,
   MockAsyncLocalStorage,
 };