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executionAsyncResource - node__async_hooks.d.ts - Node documentation
function executionAsyncResource

Usage in Deno

```typescript import { executionAsyncResource } from "node:node__async_hooks.d.ts"; ```
executionAsyncResource(): object
Resource objects returned by `executionAsyncResource()` are most often internal Node.js handle objects with undocumented APIs. Using any functions or properties on the object is likely to crash your application and should be avoided. Using `executionAsyncResource()` in the top-level execution context will return an empty object as there is no handle or request object to use, but having an object representing the top-level can be helpful. ```js import { open } from 'node:fs'; import { executionAsyncId, executionAsyncResource } from 'node:async_hooks'; console.log(executionAsyncId(), executionAsyncResource()); // 1 {} open(new URL(import.meta.url), 'r', (err, fd) => { console.log(executionAsyncId(), executionAsyncResource()); // 7 FSReqWrap }); ``` This can be used to implement continuation local storage without the use of a tracking `Map` to store the metadata: ```js import { createServer } from 'node:http'; import { executionAsyncId, executionAsyncResource, createHook, } from 'node:async_hooks'; const sym = Symbol('state'); // Private symbol to avoid pollution createHook({ init(asyncId, type, triggerAsyncId, resource) { const cr = executionAsyncResource(); if (cr) { resource[sym] = cr[sym]; } }, }).enable(); const server = createServer((req, res) => { executionAsyncResource()[sym] = { state: req.url }; setTimeout(function() { res.end(JSON.stringify(executionAsyncResource()[sym])); }, 100); }).listen(3000); ```

Return Type

object
The resource representing the current execution. Useful to store data within the resource.