# Middlewares

{% hint style="warning" %}
We moved all middlewares to separate [@nanoexpress/middlewares](https://github.com/nanoexpress/middlewares) repository
{% endhint %}

### Tested Express/Connect like Middlewares

* [body-parser](https://github.com/expressjs/body-parser) (yes, if you don't want built-in)
* [express-fileupload](https://github.com/richardgirges/express-fileupload)
* [express-cors](https://github.com/expressjs/cors)
* [express-jwt](https://github.com/auth0/express-jwt)
* [express-session](https://github.com/expressjs/session)
* [express-graphql](https://github.com/graphql/express-graphql)
* [passport](http://www.passportjs.org)

### Basic example

```javascript
app.use((req, res, next) => {
  req.appId = 'MY_APP_ID';
  next();
});
```

### Method defining

```javascript
function lazyEnd(end) {
  setTimeout(() => this.end(end), 0);
}
app.use((req, res, next) => {
  res.lazyEnd = lazyEnd;
  next();
});
```

{% hint style="info" %}
Error which comes from **Async** Middleware automacilly will be handled by **nanoexpress**
{% endhint %}


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