How to do Import and Require together?

Question

Node v14, server backend needs Observable and connection to PostgreSql.

• To create Observable, import { Observable } from 'rxjs'; is needed.
• Must add "type": "module" into pakage.json else Warning: To load an ES module, set "type": "module" in the package.json
• But it makes require not working for Postgre connection.

index.js

import { Observable } from 'rxjs';
const observable = new Observable(
  subscriber => 
  {
    ...
  });

observable.subscribe({...});
console.log('just after subscribe');

To connect to PostgreSql,

const pgp = require('pg-promise')();
const db = pgp({...});

Now getting ReferenceError: require is not defined.

How can I have both?

Answer 1

After much research and try, come back to the same spot, simply replace require with import. As an example of above,

Original:

const pgp = require('pg-promise')();
const db = pgp({...});

New:

import pgPromise from 'pg-promise';
const pgp = pgPromise({...});
const db = pgp({...});