@langchain/core
Version:
Core LangChain.js abstractions and schemas
46 lines (45 loc) • 1.71 kB
JavaScript
/* __LC_ALLOW_ENTRYPOINT_SIDE_EFFECTS__ */
import { AsyncLocalStorage } from "node:async_hooks";
import { dispatchCustomEvent as dispatchCustomEventWeb } from "./web.js";
import { ensureConfig } from "../../runnables/config.js";
import { AsyncLocalStorageProviderSingleton } from "../../singletons/index.js";
AsyncLocalStorageProviderSingleton.initializeGlobalInstance(new AsyncLocalStorage());
/**
* Dispatch a custom event.
*
* Note: this method is only supported in non-web environments
* due to usage of async_hooks to infer config.
*
* If you are using this method in the browser, please import and use
* from "@langchain/core/callbacks/dispatch/web".
*
* @param name The name of the custom event.
* @param payload The data for the custom event.
* Ideally should be JSON serializable to avoid serialization issues downstream, but not enforced.
* @param config Optional config object.
*
* @example
* ```typescript
* import { dispatchCustomEvent } from "@langchain/core/callbacks/dispatch";
*
* const foo = RunnableLambda.from(async (input: string) => {
* await dispatchCustomEvent("my_custom_event", { arbitraryField: "someval" });
* return input;
* });
*
* const callbacks = [{
* handleCustomEvent: (eventName: string, payload: any) => {
* // Logs "my_custom_event" and { arbitraryField: "someval" }
* console.log(eventName, payload);
* }
* }];
*
* await foo.invoke("hi", { callbacks })
* ```
*/
export async function dispatchCustomEvent(eventName,
// eslint-disable-next-line @typescript-eslint/no-explicit-any
payload, config) {
const ensuredConfig = ensureConfig(config);
await dispatchCustomEventWeb(eventName, payload, ensuredConfig);
}