Creating Nested Routes page
Creating nested restaurant routes.
Overview
In this part, we will:
- Create a restaurant detail component
- Add a route path with a param
- Get restaurant slug from route param in component
- Get restaurant data from service based on slug
Problem
We want to have a component to display individual restaurants details, and want the path to be nested under the restaurants path.
What you need to know
To solve this exercise you will need to know:
- How to create a nested component
- How to create a route with a param
- How to get a route param using ActivatedRoute
Route parameters & child views
A common pattern in SPA architecture is to serve a view of an individual piece of data from a path with an identifying parameter. Previously we’ve defined static paths with Angular’s router. To create a nested route, we’ll need the slug after the slash to be dynamic. We can set a token for the router parameter with :. To get the slug from the route in a component, we use the ActivatedRoute interface.
<script src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/6.2.1/rxjs.umd.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/core-js/2.5.7/core.js"/></script>
<script src="https://unpkg.com/@angular/core@7.2.0/bundles/core.umd.js"/></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/zone.js/0.8.26/zone.min.js"></script>
<script src="https://unpkg.com/@angular/common@7.2.0/bundles/common.umd.js"></script>
<script src="https://unpkg.com/@angular/compiler@7.2.0/bundles/compiler.umd.js"></script>
<script src="https://unpkg.com/@angular/router@7.2.0/bundles/router.umd.js"></script>
<script src="https://unpkg.com/@angular/platform-browser@7.2.0/bundles/platform-browser.umd.js"></script>
<script src="https://unpkg.com/@angular/platform-browser-dynamic@7.2.0/bundles/platform-browser-dynamic.umd.js"></script>
<script src="//unpkg.com/mock-url@^5.0.0" type="module"></script>
<mock-url pushstate:from="true"></mock-url>
<base href="/">
<my-app></my-app>
<script type="typescript">
const { Component, NgModule, VERSION, OnInit, Injectable } = ng.core;
const { BrowserModule } = ng.platformBrowser;
const { CommonModule } = ng.common;
const { Routes, RouterModule, ActivatedRoute } = ng.router;
interface User {
name: string;
id: number;
role: string;
}
@Injectable({
providedIn: 'root'
})
class UsersService {
private users: User[] = [
{
name: 'Jennifer',
id: 1,
role: 'admin'
},
{
name: 'Steve',
id: 2,
role: 'user'
},
{
name: 'Alice',
id: 3,
role: 'developer'
}]
constructor() { }
getUsers() {
return this.users;
}
getUser(id: string) {
return this.users.find(x => x.id === parseInt(id, 10))
}
}
@Component({
selector: 'my-app',
template: `
<ul class="nav">
<li routerLinkActive="active">
<a routerLink="/about">About</a>
</li>
<li routerLinkActive="active">
<a [routerLink]="['/users', userId]">User 1</a>
</li>
</ul>
<router-outlet></router-outlet>
`
})
class AppComponent {
userId: number = 1;
constructor() {
}
}
@Component({
selector: 'home-component',
template: `
<p>A home component!</p>
`
})
class HomeComponent {
constructor() {
}
}
@Component({
selector: 'user-component',
template: `
<p>A user component!</p>
<p *ngIf="user">
{{user.name}} is a {{user.role}}
</p>
`
})
class UserComponent implements OnInit {
user: User;
constructor(private route: ActivatedRoute, private usersService: UsersService) {
}
ngOnInit() {
const id = this.route.snapshot.paramMap.get('id');
this.user = this.usersService.getUser(id);
}
}
//THIS IS A HACK JUST FOR CODEPEN TO WORK
UserComponent.parameters = [ActivatedRoute, UsersService];
const routes: Routes = [
{ path: '', component: HomeComponent },
{ path: 'users/:id', component: UserComponent },
{ path: '**', component: HomeComponent }
]
@NgModule({
imports: [RouterModule.forRoot(routes)],
exports: [RouterModule]
})
class AppRoutingModule { }
@NgModule({
declarations: [AppComponent, HomeComponent, UserComponent],
imports: [
BrowserModule,
CommonModule,
AppRoutingModule,
],
bootstrap: [AppComponent],
providers: []
})
class AppModule {}
const { platformBrowserDynamic } = ng.platformBrowserDynamic;
platformBrowserDynamic()
.bootstrapModule(AppModule)
.catch(err => console.error(err));
</script>
Technical requirements
Create a new component called detail in the restaurant component folder that is a detail view for an individual restaurant that is served from the path '/restaurants/restaurant-slug'. Create the route as well, and use the getRestaurant method on the RestaurantService to fetch the restaurant based on the route snapshot. The detail component should have a member restaurant that is a type of Restaurant and an isLoading member set to true or false based on when the restaurant data has been fetched.
Setup
✏️ Run:
ng g component restaurant/detail
✏️ Update src/app/restaurant/detail/detail.component.html:
<ng-container *ngIf="isLoading">
<div class="loading"></div>
</ng-container>
<ng-container *ngIf="!isLoading && restaurant">
<div
class="restaurant-header"
[ngStyle]="{
'background-image': 'url(' + (restaurant.images.banner | imageUrl) + ')'
}"
>
<div class="background">
<h2>{{ restaurant.name }}</h2>
<div class="address" *ngIf="restaurant.address">
{{ restaurant.address.street }}<br />{{ restaurant.address.city }},
{{ restaurant.address.state }} {{ restaurant.address.zip }}
</div>
<div class="hours-price">
$$$<br />
Hours: M-F 10am-11pm
<span class="open-now">Open Now</span>
</div>
<br />
</div>
</div>
<div class="restaurant-content">
<h3>The best food this side of the Mississippi</h3>
<p class="description">
<img src="{{ restaurant.images.owner | imageUrl }}" />
Description for {{ restaurant.name }}
</p>
<p class="order-link">
<a class="btn" [routerLink]="['/restaurants', restaurant.slug, 'order']">
Order from {{ restaurant.name }}
</a>
</p>
</div>
</ng-container>
How to verify your solution is correct
When you click the detail button on a restaurant from the restaurant list view you’ll see the detail view of that restaurant.
✏️ Update the spec file src/app/restaurant/detail/detail.component.spec.ts to be:
import { ComponentFixture, TestBed } from '@angular/core/testing';
import { ActivatedRoute } from '@angular/router';
import { RouterTestingModule } from '@angular/router/testing';
import { of } from 'rxjs';
import { ImageUrlPipe } from '../../image-url.pipe';
import { RestaurantService } from '../restaurant.service';
import { DetailComponent } from './detail.component';
class MockRestaurantService {
getRestaurant(slug: string) {
return of({
name: 'Poutine Palace',
slug: 'poutine-palace',
images: {
thumbnail: 'node_modules/place-my-order-assets/images/4-thumbnail.jpg',
owner: 'node_modules/place-my-order-assets/images/3-owner.jpg',
banner: 'node_modules/place-my-order-assets/images/2-banner.jpg',
},
menu: {
lunch: [
{
name: 'Crab Pancakes with Sorrel Syrup',
price: 35.99,
},
{
name: 'Steamed Mussels',
price: 21.99,
},
{
name: 'Spinach Fennel Watercress Ravioli',
price: 35.99,
},
],
dinner: [
{
name: 'Gunthorp Chicken',
price: 21.99,
},
{
name: 'Herring in Lavender Dill Reduction',
price: 45.99,
},
{
name: 'Chicken with Tomato Carrot Chutney Sauce',
price: 45.99,
},
],
},
address: {
street: '230 W Kinzie Street',
city: 'Green Bay',
state: 'WI',
zip: '53205',
},
_id: '3ZOZyTY1LH26LnVw',
});
}
}
const MockActivatedRoute = {
snapshot: {
paramMap: {
get() {
return 'poutine-palace';
},
},
},
};
describe('DetailComponent', () => {
let component: DetailComponent;
let fixture: ComponentFixture<DetailComponent>;
beforeEach(async () => {
await TestBed.configureTestingModule({
declarations: [DetailComponent, ImageUrlPipe],
imports: [RouterTestingModule],
providers: [
{
provide: RestaurantService,
useClass: MockRestaurantService,
},
{
provide: ActivatedRoute,
useValue: MockActivatedRoute,
},
],
}).compileComponents();
});
beforeEach(() => {
fixture = TestBed.createComponent(DetailComponent);
component = fixture.componentInstance;
fixture.detectChanges();
});
it('should create', () => {
expect(component).toBeTruthy();
});
it('should have an isLoading member set to true by default', () => {
const fixture = TestBed.createComponent(DetailComponent);
expect(fixture.componentInstance.isLoading).toEqual(true);
});
it('should get a restaurant based on route slug', () => {
const mockRestaurant = {
name: 'Poutine Palace',
slug: 'poutine-palace',
images: {
thumbnail: 'node_modules/place-my-order-assets/images/4-thumbnail.jpg',
owner: 'node_modules/place-my-order-assets/images/3-owner.jpg',
banner: 'node_modules/place-my-order-assets/images/2-banner.jpg',
},
menu: {
lunch: [
{
name: 'Crab Pancakes with Sorrel Syrup',
price: 35.99,
},
{
name: 'Steamed Mussels',
price: 21.99,
},
{
name: 'Spinach Fennel Watercress Ravioli',
price: 35.99,
},
],
dinner: [
{
name: 'Gunthorp Chicken',
price: 21.99,
},
{
name: 'Herring in Lavender Dill Reduction',
price: 45.99,
},
{
name: 'Chicken with Tomato Carrot Chutney Sauce',
price: 45.99,
},
],
},
address: {
street: '230 W Kinzie Street',
city: 'Green Bay',
state: 'WI',
zip: '53205',
},
_id: '3ZOZyTY1LH26LnVw',
};
expect(fixture.componentInstance.restaurant).toEqual(mockRestaurant);
});
});
✏️ Update the spec file src/app/app.component.spec.ts to be:
import { Location } from '@angular/common';
import { HttpClientModule } from '@angular/common/http';
import { NO_ERRORS_SCHEMA } from '@angular/core';
import {
ComponentFixture,
fakeAsync,
flush,
TestBed,
tick,
} from '@angular/core/testing';
import { ReactiveFormsModule } from '@angular/forms';
import { Router } from '@angular/router';
import { of } from 'rxjs';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { HomeComponent } from './home/home.component';
import { ImageUrlPipe } from './image-url.pipe';
import { DetailComponent } from './restaurant/detail/detail.component';
import { RestaurantComponent } from './restaurant/restaurant.component';
import { RestaurantService } from './restaurant/restaurant.service';
class MockRestaurantService {
getRestaurants() {
return of({
data: [
{
name: 'Poutine Palace',
slug: 'poutine-palace',
images: {
thumbnail:
'node_modules/place-my-order-assets/images/4-thumbnail.jpg',
owner: 'node_modules/place-my-order-assets/images/3-owner.jpg',
banner: 'node_modules/place-my-order-assets/images/2-banner.jpg',
},
menu: {
lunch: [
{
name: 'Crab Pancakes with Sorrel Syrup',
price: 35.99,
},
{
name: 'Steamed Mussels',
price: 21.99,
},
{
name: 'Spinach Fennel Watercress Ravioli',
price: 35.99,
},
],
dinner: [
{
name: 'Gunthorp Chicken',
price: 21.99,
},
{
name: 'Herring in Lavender Dill Reduction',
price: 45.99,
},
{
name: 'Chicken with Tomato Carrot Chutney Sauce',
price: 45.99,
},
],
},
address: {
street: '230 W Kinzie Street',
city: 'Green Bay',
state: 'WI',
zip: '53205',
},
_id: '3ZOZyTY1LH26LnVw',
},
{
name: 'Cheese Curd City',
slug: 'cheese-curd-city',
images: {
thumbnail:
'node_modules/place-my-order-assets/images/2-thumbnail.jpg',
owner: 'node_modules/place-my-order-assets/images/3-owner.jpg',
banner: 'node_modules/place-my-order-assets/images/2-banner.jpg',
},
menu: {
lunch: [
{
name: 'Ricotta Gnocchi',
price: 15.99,
},
{
name: 'Gunthorp Chicken',
price: 21.99,
},
{
name: 'Garlic Fries',
price: 15.99,
},
],
dinner: [
{
name: 'Herring in Lavender Dill Reduction',
price: 45.99,
},
{
name: 'Truffle Noodles',
price: 14.99,
},
{
name: 'Charred Octopus',
price: 25.99,
},
],
},
address: {
street: '2451 W Washburne Ave',
city: 'Green Bay',
state: 'WI',
zip: '53295',
},
_id: 'Ar0qBJHxM3ecOhcr',
},
],
});
}
getStates() {
return of({
data: [
{ short: 'MO', name: 'Missouri' },
{ short: 'CA ', name: 'California' },
{ short: 'MI', name: 'Michigan' },
],
});
}
getCities(state: string) {
return of({
data: [
{ name: 'Sacramento', state: 'CA' },
{ name: 'Oakland', state: 'CA' },
],
});
}
getRestaurant(slug: string) {
return of({
name: 'Poutine Palace',
slug: 'poutine-palace',
images: {
thumbnail: 'node_modules/place-my-order-assets/images/4-thumbnail.jpg',
owner: 'node_modules/place-my-order-assets/images/3-owner.jpg',
banner: 'node_modules/place-my-order-assets/images/2-banner.jpg',
},
menu: {
lunch: [
{
name: 'Crab Pancakes with Sorrel Syrup',
price: 35.99,
},
{
name: 'Steamed Mussels',
price: 21.99,
},
{
name: 'Spinach Fennel Watercress Ravioli',
price: 35.99,
},
],
dinner: [
{
name: 'Gunthorp Chicken',
price: 21.99,
},
{
name: 'Herring in Lavender Dill Reduction',
price: 45.99,
},
{
name: 'Chicken with Tomato Carrot Chutney Sauce',
price: 45.99,
},
],
},
address: {
street: '230 W Kinzie Street',
city: 'Green Bay',
state: 'WI',
zip: '53205',
},
_id: '3ZOZyTY1LH26LnVw',
});
}
}
describe('AppComponent', () => {
let fixture: ComponentFixture<AppComponent>;
let location: Location;
let router: Router;
beforeEach(async () => {
await TestBed.configureTestingModule({
imports: [AppRoutingModule, HttpClientModule, ReactiveFormsModule],
declarations: [
AppComponent,
HomeComponent,
RestaurantComponent,
ImageUrlPipe,
DetailComponent,
],
providers: [
{ provide: RestaurantService, useClass: MockRestaurantService },
],
schemas: [NO_ERRORS_SCHEMA],
})
.overrideComponent(RestaurantComponent, {
set: { template: '<p>I am a fake restaurant component</p>' },
})
.compileComponents();
fixture = TestBed.createComponent(AppComponent);
location = TestBed.inject(Location);
router = TestBed.inject(Router);
});
it('should create the app', () => {
const app = fixture.componentInstance;
expect(app).toBeTruthy();
});
it(`should have as title 'place-my-order'`, () => {
const app = fixture.componentInstance;
expect(app.title).toEqual('place-my-order');
});
it('should render title in a h1 tag', () => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
expect(compiled.querySelector('h1')?.textContent).toContain(
'place-my-order.com'
);
});
it('should render the HomeComponent with router navigates to "/" path', fakeAsync(() => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
router.navigate(['']).then(() => {
expect(location.path()).toBe('');
expect(compiled.querySelector('pmo-home')).not.toBe(null);
});
}));
it('should render the RestaurantsComponent with router navigates to "/restaurants" path', fakeAsync(() => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
router.navigate(['restaurants']).then(() => {
expect(location.path()).toBe('/restaurants');
expect(compiled.querySelector('pmo-restaurant')).not.toBe(null);
});
}));
it('should render the DetailComponent with router navigates to "/restaurants/slug" path', fakeAsync(() => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
router.navigate(['restaurants/crab-shack']).then(() => {
expect(location.path()).toBe('/restaurants/crab-shack');
expect(compiled.querySelector('pmo-detail')).not.toBe(null);
});
}));
it('should have the home navigation link href set to "/"', () => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
const homeLink = compiled.querySelector('li a');
const href = homeLink?.getAttribute('href');
expect(href).toEqual('/');
});
it('should have the restaurants navigation link href set to "/restaurants"', () => {
fixture.detectChanges();
const compiled = fixture.nativeElement as HTMLElement;
const restaurantsLink = compiled.querySelector('li:nth-child(2) a');
const href = restaurantsLink?.getAttribute('href');
expect(href).toEqual('/restaurants');
});
it('should make the home navigation link class active when the router navigates to "/" path', fakeAsync(() => {
const compiled = fixture.nativeElement as HTMLElement;
router.navigate(['']);
fixture.detectChanges();
tick();
fixture.detectChanges();
const homeLinkLi = compiled.querySelector('li');
expect(homeLinkLi?.classList).toContain('active');
expect(compiled.querySelectorAll('.active').length).toBe(1);
flush();
}));
it('should make the restaurants navigation link class active when the router navigates to "/restaurants" path', fakeAsync(() => {
const compiled = fixture.nativeElement as HTMLElement;
router.navigate(['restaurants']);
fixture.detectChanges();
tick();
fixture.detectChanges();
expect(location.path()).toBe('/restaurants');
const restaurantsLinkLi = compiled.querySelector('li:nth-child(2)');
expect(restaurantsLinkLi?.classList).toContain('active');
expect(compiled.querySelectorAll('.active').length).toBe(1);
flush();
}));
});
Solution
If you’ve implemented the solution correctly, the tests will pass when you run npm run test!
Click to see the solution
✏️ Update src/app/app-routing.module.tsimport { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';
import { HomeComponent } from './home/home.component';
import { DetailComponent } from './restaurant/detail/detail.component';
import { RestaurantComponent } from './restaurant/restaurant.component';
const routes: Routes = [
{
path: '',
component: HomeComponent,
},
{
path: 'restaurants',
component: RestaurantComponent,
},
{
path: 'restaurants/:slug',
component: DetailComponent,
},
];
@NgModule({
imports: [RouterModule.forRoot(routes)],
exports: [RouterModule],
})
export class AppRoutingModule {}
✏️ Update src/app/restaurant/detail/detail.component.ts
import { Component, OnDestroy, OnInit } from '@angular/core';
import { ActivatedRoute } from '@angular/router';
import { Subject, takeUntil } from 'rxjs';
import { Restaurant } from '../restaurant';
import { RestaurantService } from '../restaurant.service';
@Component({
selector: 'pmo-detail',
templateUrl: './detail.component.html',
styleUrl: './detail.component.css'
})
export class DetailComponent implements OnInit, OnDestroy {
restaurant?: Restaurant;
isLoading: boolean = true;
private onDestroy$ = new Subject<void>();
constructor(
private route: ActivatedRoute,
private restaurantService: RestaurantService
) {}
ngOnInit(): void {
const slug = this.route.snapshot.paramMap.get('slug');
if (slug) {
this.restaurantService
.getRestaurant(slug)
.pipe(takeUntil(this.onDestroy$))
.subscribe((data: Restaurant) => {
this.restaurant = data;
this.isLoading = false;
});
}
}
ngOnDestroy(): void {
this.onDestroy$.next();
this.onDestroy$.complete();
}
}