How to use the @bugsnag/js.init function in @bugsnag/js

import React from 'react'
import ReactDOM from 'react-dom'
import './index.css'
import App from './App'

import Bugsnag from '@bugsnag/js'
import bugsnagReact from '@bugsnag/plugin-react'

Bugsnag.init('YOUR_API_KEY')
Bugsnag.use(bugsnagReact, React)

const ErrorBoundary = Bugsnag.getPlugin('react')

const ErrorScreen = () =>
  <div>
    <h1><span aria-label="warning icon" role="img">⚠️</span> Error <span aria-label="warning icon" role="img">⚠️</span></h1>
    <p><strong>Uh oh, there was an error in the component tree!</strong></p>
    <p>This <code>FallbackComponent</code> prop can be used to show something useful to your users when such errors occur.</p>
  </div>

const onError = event =&gt; {
  // You can also provide an onError callback to run just on errors caught by
  // the error boundary. Maybe you want to attach some of the current state from
  // whatever model/store you're using (e.g redux)
  console.log('about to send this event', { event })

import { BrowserModule } from '@angular/platform-browser';
import { NgModule, ErrorHandler } from '@angular/core';
// import our Angular plugin
import { BugsnagErrorHandler } from '@bugsnag/plugin-angular';
// import the bugsnag-js client you initialized in bugsnag.ts
import Bugsnag from '@bugsnag/js';
import { AppComponent } from './app.component';

Bugsnag.init('YOUR_API_KEY')

// There are certain errors within Angular that get caught by its own error handler
// and only logged to the console. These errors will never make it to Bugsnag by
// themselves and so require a little wiring up.
export function errorHandlerFactory() {
  return new BugsnagErrorHandler()
}

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule
  ],
  providers: [ { provide: ErrorHandler, useFactory: errorHandlerFactory } ],

// include Bugsnag from the installed dependencies
import Bugsnag from '@bugsnag/js'

const apiKey: string = process.env.BUGSNAG_API_KEY ? process.env.BUGSNAG_API_KEY : ''

// initialise Bugsnag with some basic options
Bugsnag.init({
  // this loads the apiKey from the environment so be sure to pass it in
  apiKey: apiKey,
  // setting the appVersion is useful to track when errors are introduced/fixed
  appVersion: '1.2.3',
  // using a combination of releaseStage/notifyReleaseStages you can ensure you
  // only get reports from the environments you care about
  releaseStage: 'production',
  enabledReleaseStages: [ 'staging', 'production' ],
  // you can set global metadata when you initialise Bugsnag
  metadata: {}
})

console.log(`
  Welcome to the plain TypeScript example app. Type one of the
  following keys, followed by enter, to perform each action:

import Vue from 'vue'
import Bugsnag from '@bugsnag/js'
import bugsnagVue from '@bugsnag/plugin-vue'
Bugsnag.init('<%= options.apiKey %>')
Bugsnag.use(bugsnagVue, Vue)

export default function ({ app }, inject) {
  inject('Bugsnag', Bugsnag)
}

import Vue from 'vue'
import App from './App.vue'

import Bugsnag from '@bugsnag/js'
import bugsnagVue from '@bugsnag/plugin-vue'

Bugsnag.init('YOUR_API_KEY')
Bugsnag.use(bugsnagVue, Vue)

Vue.config.productionTip = false

new Vue({
  render: h => h(App)
}).$mount('#app')

const Bugsnag = require('@bugsnag/js')
const Koa = require('koa')
const router = require('koa-router')
const serve = require('koa-static')
const mount = require('koa-mount')
const { readFileSync } = require('fs')

Bugsnag.init(process.env.BUGSNAG_API_KEY)
Bugsnag.use(require('@bugsnag/plugin-koa'))

const app = new Koa()
const { requestHandler, errorHandler } = Bugsnag.getPlugin('koa')

app.use(requestHandler)

app.use(mount('/static', serve(`${__dirname}/static`)))

const index = readFileSync('./views/index.html', 'utf8')

app.use(
  router()
    .get('/', (ctx, next) => {
      ctx.body = index
    })

import React from 'react'
import Bugsnag from '@bugsnag/js'
import bugsnagReact from '@bugsnag/plugin-react'
import getConfig from 'next/config'
const { serverRuntimeConfig, publicRuntimeConfig } = getConfig()

Bugsnag.init({
  apiKey: serverRuntimeConfig.BUGSNAG_API_KEY || publicRuntimeConfig.BUGSNAG_API_KEY
})
Bugsnag.use(bugsnagReact, React)

export default Bugsnag

export default function (options) {
  const logger = consola.withScope('Bugsnag')
  logger.info('Configuring')

  const bugsnagOptions = { ...this.options.bugsnag, ...options.bugsnag }

  logger.info('Adding browser plugin')
  this.addPlugin({
    src: join(__dirname, 'client.js'),
    options: { apiKey: bugsnagOptions.browserApiKey },
    ssr: false
  })

  Bugsnag.init({ apiKey: bugsnagOptions.serverApiKey, logger })
  Bugsnag.use(bugsnagExpress)

  logger.info('Adding server handlers')
  this.nuxt.hook('render:setupMiddleware', app => app.use(Bugsnag.getPlugin('express').requestHandler))
  this.nuxt.hook('render:errorMiddleware', app => app.use(Bugsnag.getPlugin('express').errorHandler))
  this.nuxt.hook('generate:routeFailed', ({ route, errors }) => {
    errors.forEach(({ error }) => Bugsnag.notify(error, event => event.addMetadata('route', route)))
  })
}