local-storage

AsyncLocalStorage middleware.

Install

npm i @xpr/local-storage

Usage

import { localStorage, getStore } from '@xpr/local-storage';

const app = express();

// The middleware starts an async hooks trap.
// 
// From now on, every function called after
// this middleware run, can access the [[Request]]
// and the [[Response]] of the same context using
// the [[getStore]] function.
app.use(localStorage());

app.use((req, res, next) => {
  req.locals.RAND = generateRandNumber();
});


function logger(message: string) {
  const store = getStore();
  if (store) {
    // we've been called from inside async trap
    // we can use the store content
    const id = store.request.locals.RAND;
    console.log(id, message);
  } else {
    console.log(null, message);
  }
}

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