asyncUtilsExpress.js

const asyncMiddleware = require('./utils/asyncMiddleware');

router.get('/users/:id', asyncMiddleware(async (req, res, next) => {
    /* 
      if there is an error thrown in getUserFromDb, asyncMiddleware
      will pass it to next() and express will handle the error;
    */
    const user = await getUserFromDb({ id: req.params.id })
    res.json(user);
}));

router.post('/users', asyncMiddleware(async (req, res, next) => {
  const user = await makeNewUser(req.body);
  res.json(user)
}))