Asyncify Express

Pass async/await functions to express route handlers.

Requirements

You must use a node version that supports promises and the Proxy library.

Installation

NPM

npm install asyncify-express

Yarn

yarn add asyncify-express

Motivation

You can pass async functions to route handlers. However, Express will run them like regular functions. Therefore, any errors will not be caught and processed appropriately because errors inside async functions have to be caught explicitly i.e. (async () => {...})().catch(err => ...). Otherwise they will silently fail. Therefore, this library uses a Proxy to trap any HTTP Verb methods on the express app object and explicitly catches errors and passes them on to the Express next handler to be handled like regular functions.

Use

import express from 'express';
import asyncifyExpress from ('../async-express');

const app = asyncifyExpress(express());

app.get('/users', async (req, res) => {
  const users = await getAllUsers();
  res.json(users);
});

Note that because the library uses a proxy, it only wraps the get, post, delete, put, patch functions. Other functions get safely passed on to the original express() app.