Angular 6 vendor and main js taking too much time to load the data

Question

I dont understand why in my project scripting is taking too much time to load the page. It look like angular 6 is taking time in loading css and js from assest folder as well its taking time to load vendor and main js. I dont understand why its happening.

below is my routing file

import { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';
import { AppComponent } from './app.component';
import { LoginComponent } from './login/login.component';
import { DashboardComponent } from './dashboard/dashboard.component';
import { AuthGuard } from './auth-guard.service';
import { TeamCardComponent } from './team-card/team-card.component';
import { TeamComponent } from './team/team.component';
import { TeamDetailsComponent } from './team-details/team-details.component';
import { PipelineComponent } from './pipeline/pipeline.component';
import { ProfileComponent } from './profile/profile.component';
import { LeadsComponent } from './leads/leads.component';
import { TestpopupComponent } from './testpopup/testpopup.component';
import { CreateleadComponent } from './createlead/createlead.component';
import { ProductsComponent } from './products/products.component';
import { CreateTeamComponent } from './create-team/create-team.component';
import { CreatePipelineComponent } from './create-pipeline/create-pipeline.component';
import { PipelineDetailsComponent } from './pipeline-details/pipeline-details.component';
import { FormValidationComponent } from './form-validation/form-validation.component';
import { AssociateDashboardComponent } from './associate-dashboard/associate-dashboard.component';
import { AssociateProfileComponent } from './associate-profile/associate-profile.component';
import { AssociateProductComponent } from './associate-product/associate-product.component';
import { AssociateCalendarComponent } from './associate-calendar/associate-calendar.component';
import { AssociateLeadComponent } from './associate-lead/associate-lead.component';
import { TwilioVideoComponent } from './twilio-video/twilio-video.component';
import { CreateUpdateProductComponent } from './create-product-new/create-product-new.component';
import { UnAuthenticatedTaskListComponent } from './un-authenticated-task-list/un-authenticated-task-list.component';
import { ProductSignalDemoComponent } from './product-signal-demo/product-signal-demo.component';

const routes: Routes = [
  { path: '', redirectTo: 'login', pathMatch: 'full' },
  { path: 'app', component: AppComponent },
  { path: 'login', component: LoginComponent },
  { path: 'dashboard', component: DashboardComponent, canActivate: [AuthGuard] },
  { path: 'teams', component: TeamComponent, canActivate: [AuthGuard] },
  { path: 'teamdetail/:id', component: TeamDetailsComponent, canActivate: [AuthGuard] },
  { path: 'pipeline', component: PipelineComponent, canActivate: [AuthGuard] },
  { path: 'profile', component: ProfileComponent, canActivate: [AuthGuard] },
  { path: 'leads', component: LeadsComponent, canActivate: [AuthGuard] },
  { path: 'testpopup', component: TestpopupComponent, canActivate: [AuthGuard] },
  { path: 'createlead', component: CreateleadComponent, canActivate: [AuthGuard] },
  { path: 'products', component: ProductsComponent, canActivate: [AuthGuard] },
  { path: 'createteam', component: CreateTeamComponent, canActivate: [AuthGuard] },
  { path: 'create-pipeline', component: CreatePipelineComponent, canActivate: [AuthGuard] },
  { path: 'pipeline-details/:id', component: PipelineDetailsComponent, canActivate: [AuthGuard] },
  // { path: 'form-validation', component: FormValidationComponent, canActivate: [AuthGuard] },
  { path: 'dashboard-associate', component: AssociateDashboardComponent, canActivate: [AuthGuard] },
  { path: 'profile-associate', component: AssociateProfileComponent, canActivate: [AuthGuard] },
  { path: 'product-associate', component: AssociateProductComponent, canActivate: [AuthGuard] },
  { path: 'calendar-associate', component: AssociateCalendarComponent, canActivate: [AuthGuard] },
  { path: 'lead-associate', component: AssociateLeadComponent, canActivate: [AuthGuard] },
  { path: 'twilio-video', component: TwilioVideoComponent },
  { path: 'productedit/:productId', component: CreateUpdateProductComponent, canActivate: [AuthGuard] },
  { path: 'demo', component: UnAuthenticatedTaskListComponent },
  { path: 'signals', component: ProductSignalDemoComponent },
];


@NgModule({
  imports: [RouterModule.forRoot(routes, { useHash: true })],
  exports: [RouterModule]
})
export class AppRoutingModule { }

this is my index.html code for loading css and js

<!doctype html>
<html lang="en">

<head>
  <meta charset="utf-8">
  <title>Tant</title>
  <base href="/">
  <meta http-equiv="x-ua-compatible" content="IE=9">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="assets/css/bootstrap.min.css">
  <link rel="stylesheet" type="text/css" href="assets/css/jquery.dataTables.css" />
  <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
  <link rel="stylesheet" type="text/css" href="assets/css/ngselect.css" />

  <link rel="stylesheet" type="text/css" href="assets/css/dropzone.css" />
  <link rel="stylesheet" type="text/css" href="assets/css/font-awesome.css" />
  <link rel="stylesheet" type="text/css" href="assets/css/all.css" />
  <link rel="stylesheet" type="text/css" href="assets/css/font-family-Lato.css" />
  <link href="../node_modules/intl-tel-input/build/css/intlTelInput.css" rel="stylesheet">
  <link rel="stylesheet" href="/node_modules/owl.carousel/dist/assets/owl.carousel.min.css">
  <link rel="stylesheet" href="/node_modules/owl.carousel/dist/assets/owl.theme.default.min.css">


  <!-- <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.3.1/css/all.css" integrity="sha384-mzrmE5qonljUremFsqc01SB46JvROS7bZs3IO2EmfFsd15uHvIt+Y8vEf7N7fWAU"
    crossorigin="anonymous"> -->


  <link rel="icon" type="image/x-icon" href="favicon.png">
</head>

<body class="background position-relative">
  <app-root></app-root>
  <script src="assets/js/jquery-3.3.1.slim.min.js"></script>
  <script src="assets/js/popper.min.js"></script>
  <script src="assets/js/bootstrap.min.js"></script>
  <script src="assets/js/jquery.dataTables.js"></script>
  <!-- <script src="assets/js/twilio.min.js"></script> -->
  <script type="text/javascript" src="assets/js/twilio.min.js"></script>
  <script src="assets/js/intlTelInput.js"></script>
  <script src="../node_modules/intl-tel-input/build/js/utils.js"></script>
  <script type="application/javascript" src="assets/js/owl.carousel.js"></script>




</body>

</html>

I am loading css and js from asset folder but still its taking 23-30 second to load the page which is too much.

I have a single module and multiple component project. Even if i comment my logic empty component is taking 10 seconds for loading css and js. Event after caching css and js its taking 8 seconds for displaying an empty component. What should i do please suggest

Answer 1

This may happen due to incorrect web-pack bundling. so please do this

1.just open the package.json, 
2.modify the "devDependencies" section,
3.add line "webpack-sources": "1.2.0",

then yarn or npm update

and other thing is you need to lazy load components. sometimes it can't logically group in to modules but the seek of loading and performance you have to do it. then main.js size will be break and loaded on demand .

also try to compile with --aot and it will give you a huge impact on performance