How to use koa.js + next in Firebase Functions – Shopify

I want to use Cloud Functions for Firebase to deploy the React application for shopify app.

I am new to both Next and Koa.

Based on this repo the below code is how to host a simple react application in Firebase.

const path = require('path')
const functions = require('firebase-functions')
const next = require('next')

var dev = process.env.NODE_ENV !== 'production'
var app = next({
  dev,
  conf: { distDir: `${path.relative(process.cwd(), __dirname)}/next` }
})
var handle = app.getRequestHandler()

exports.next = functions.https.onRequest((req, res) => {
  console.log('File: ' + req.originalUrl) // log the page.js file that is being requested
  return app.prepare().then(() => handle(req, res))
})

Which works correctly, no issue.

Then based on this tutorial from shopify I need to integrate koa and other dependencies in server.js, which in my case I believe it should be placed inside the firebase function. so I get to this code

const path = require('path')
const isomorphicFetch = require('isomorphic-fetch');
const Koa = require('koa');
const functions = require('firebase-functions')
const next = require('next');
const ShopifyConfig = require('./shopify.js');

const { default: createShopifyAuth } = require('@shopify/koa-shopify-auth');
const dotenv = require('dotenv');
const { verifyRequest } = require('@shopify/koa-shopify-auth');
const session = require('koa-session');

dotenv.config();

const port = parseInt(process.env.PORT, 10) || 3000;

var dev = process.env.NODE_ENV !== 'production'
var app = next({
  dev,
  conf: { distDir: `${path.relative(process.cwd(), __dirname)}/next` }
})
var handle = app.getRequestHandler()

const server = new Koa();

server.use(session(server));
server.keys = [ShopifyConfig.secretKey];

server.use(
  createShopifyAuth({
    apiKey: ShopifyConfig.key,
    secret: ShopifyConfig.secretKey,
    scopes: [],
    afterAuth(ctx) {
      const { shop, accessToken } = ctx.session;
      ctx.redirect('/');
    },
  }),
);

server.use(verifyRequest());

server.use(async (ctx) => {
  await handle(ctx.req, ctx.res);
  ctx.respond = false;
  ctx.res.statusCode = 200;

});

exports.next = functions.https.onRequest((req, res) => {
  console.log('File: ' + req.originalUrl) // 

  // This is old code
  // return app.prepare().then(() => {
  //   handle(req, res);
  // })

  // I tried this #1
  // server.callback(req, res);
})

// I tried this #2
// exports.next = functions.https.onRequest(server.callback);

// I tried this #3
// exports.next = functions.https.onRequest(server.callback());

// I tried this #4
exports.next = functions.https.onRequest((req, res) => {
  console.log('File: ' + req.originalUrl) 

  return app.prepare().then(() => {
    server.callback(req, res);
    //handle(req, res);
  })
})

My question is now based on Koa what code should be in functions.https.onRequest ? please note there is no code to listen to port since it doesn’t make sense for firebase functions.

I tried #1, #2, #3, as well as this post

1 -> I get request timeout

2 -> I get request timeout

3 -> I get “Cannot access middleware of undefined”

4 -> I get request timeout