Exporting and requiring an async function error

Question

I export an async function in a file called resourcess.js like this:

//resourcess.js
module.exports = function(arg) {
    let do_stuff = async (arg) => {
    ...
}

Then i require that file in routes.js like this:

let importedFunc = require('./resourcess.js');

Finally i use it in routes.js like this:

app.post('/post', function(req, res) {
        var a2 = req.body.a1;
        importedFunc(a2).then(result => {
            console.log(result);
        res.render('index.ejs');
        }).catch(err => {
            console.log(err);
            res.render('index.ejs');
        })
    });

This is the error message i get:

TypeError: Cannot read property 'then' of undefined

I cannot understand what i am doing wrong....

Answer 1

If you're not calling do_stuff and returning the promise, then the exported function isn't actually returning a promise:

//resourcess.js
module.exports = function(arg) {
    let do_stuff = async (arg) => {
      // something should be done inside this function
      let data = await somethingThatReturnsData(arg);
      return data;
    };
    return do_stuff(arg);
}

But from how this is being used, I think you want to do the following:

//resourcess.js
// see that async is on the actual exported function
module.exports = async function(arg) {
  let data = await somethingThatReturnsData(arg);
  // do stuff to data
  return data;
};