Replace the use of 'require' by 'import' to reduce library side and improve performance. (Tree shaking)

[sadortun]

New Feature / Enhancement Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.

Current Limitation

Follow up of the discussion on #203

Currently, the SDK is imported globally, and the compilers cannot optimize the imports and remove unused code.

Firebase have a great explanation
https://firebase.googleblog.com/2021/08/the-new-firebase-js-sdk-now-ga.html?m=1

Feature / Enhancement Description

This would allow to reduce the compiled client side app by eliminating the unused code.

This would also allow to fix #203 by allowing to create instances the Parse library for those who need to interact with multiple Servers.

Example Use Case

Alternatives / Workarounds

3rd Party References

https://www.codingame.com/playgrounds/7463/tree-shaking-in-javascript-with-rollup

[dplewis]

@sadortun @mtrezza I tried to replace require with import but ran into an issue with babel

I used import on EventEmitter.ts

import RNEventEmitter from 'react-native/Libraries/vendor/emitter/EventEmitter';
import { EventEmitter as NodeEventEmitter } from 'events';
let EventEmitter: any;

try {
  if (process.env.PARSE_BUILD === 'react-native') {
    EventEmitter = RNEventEmitter;
    EventEmitter.prototype.on = EventEmitter.prototype.addListener;
  } else {
    EventEmitter = NodeEventEmitter;
  }
} catch (_) {
  // EventEmitter unavailable
}
module.exports = EventEmitter;
export default EventEmitter;

Babel outputs to lib/node.js, as you can see the dead code has been eliminated but the unused import _EventEmitter didn't get removed. Are there any babel experts that would like to have a look?

var _EventEmitter = _interopRequireDefault(require("react-native/Libraries/vendor/emitter/EventEmitter"));
var _events = require("events");
var EventEmitter;
try {
  EventEmitter = _events.EventEmitter;
} catch (_) {
  // EventEmitter unavailable
}
module.exports = EventEmitter;
var _default = EventEmitter;
exports.default = _default;

There are a few workarounds

• Dynamic Imports with top level await?
• Override the EventEmitter is already supported
• Use an isomorphic EventEmitter library see discussion Isomorphic javascript client library. #1258
• Create our own EventEmitter in memory (isomorphic support)
• Fix unused imports for Babel

This is also an issue with the CryptoController.