the example code for express is not working correctly

[Pusikas]

When working with ESM, then using the following example code does not work anymore with v2.0.1:

import express from 'express';
import useragent from 'express-useragent';

const app = express();

app.use(useragent.express());

The default export does not have a function called express().

What does work is the following:

import express from 'express';
import * as useragent from 'express-useragent';

const app = express();

app.use(useragent.express());

You can also import the exported function itself, but that will collide with the express-import, so you have to rename:

import express from 'express';
import { express as mw } from 'express-useragent';

const app = express();

app.use(mw());

You may want to update your documentation here. The example still works for CommonJS code using require().

[jsdev-robin]

You’re correct — the current example in the docs uses the CommonJS require() style, which works for older setups, but when using ESM with Express 5.x and express-useragent v2.0.1, the default import no longer exposes an express() function.

you can use like this way:

  const source = req.headers['user-agent'] ?? 'unknown';
  const parser = new UserAgent().hydrate(source);