Async Await in firebase functions

Question

I'm using Async/Await in a firebase function as follows

const functions = require("firebase-functions");
const puppeteer = require('puppeteer');

async function getHtml(url) {
    const browser = await puppeteer.launch({
        headless: true,
        args: ['--no-sandbox', '--disable-setuid-sandbox',]
    });

    const page = await browser.newPage();

    await page.goto(url,
        { waitUntil: ['networkidle0', 'networkidle2', 'load', 'domcontentloaded'] });
    const k = await page.content()

    await browser.close();
    return k
};

// Create and deploy your first functions
// https://firebase.google.com/docs/functions/get-started

exports.api = functions.runWith({ memory: '512MB' })
    .https.onRequest((request, response) => {
        // console.log(request.query.url)
        functions.logger.info("Hello logs!", { structuredData: true });
        getHtml(request.query.url)
            .then(function (res) {
                response.send(res);
                console.log(res)
            })
            .catch(function (err) {
                response.send(err);
            })

    })
    ;

This fails the pre-deploy with the error Parsing error: Unexpected token function for the line async function getHtml(url) {

I just assumed that it's an issue with the eslint which is why I removed the predeploy "predeploy": [ "npm --prefix \"$RESOURCE_DIR\" run lint"] in the firebase json which helped me deploy successfully but returned an empty response on testing out the deployed code.

Everything on my local system works flawlessly with firebase serve

Any help would be much appriciated!

---

Edit:

Steps to reproduce

• run firebase init in a directory
• Select functions... , Javascript and (optionally)select no for eslint
• install puppeteer using npm and paste the code above in the /functions/index.js file
• run firebase serve and test the code with a url parameter on your local system. This will respond with a rendered html page.
• Run firebase deploy

Now, on going to the hosted URL and appending a url parameter should just return {} instead of the html