PromucFlow_constructor/app/client/src/utils/AppsmithUtils.tsx

import FontFaceObserver from 'fontfaceobserver'
import { ReduxAction } from "../constants/ActionConstants"
import { SENTRY_PROD_CONFIG, SENTRY_STAGE_CONFIG, HOTJAR_PROD_HJID, HOTJAR_PROD_HJSV } from "../constants/ThirdPartyConstants";
import * as Sentry from '@sentry/browser';
import AnalyticsUtil from "./AnalyticsUtil"
import netlifyIdentity from 'netlify-identity-widget';

export const createReducer = (
  initialState: any,
  handlers: { [type: string]: Function }
) => {
  return function reducer(state = initialState, action: ReduxAction<any>) {
    if (handlers.hasOwnProperty(action.type)) {
      return handlers[action.type](state, action)
    } else {
      return state
    }
  }
}

export const appInitializer = () => {
  netlifyIdentity.init();
  switch (process.env.REACT_APP_ENVIRONMENT) {
    case "PRODUCTION":
      Sentry.init(SENTRY_PROD_CONFIG);    
      AnalyticsUtil.initializeHotjar(HOTJAR_PROD_HJID, HOTJAR_PROD_HJSV);
      AnalyticsUtil.initializeSegment();
      break;
    case "STAGING":
        Sentry.init(SENTRY_STAGE_CONFIG);
      break
    case "LOCAL":
      break;
  }

  const textFont = new FontFaceObserver("DM Sans");
  textFont.load().then(()=> {
    document.body.className += "fontLoaded";
  }).catch(err => {
    console.log(err);
  });
}