ngn-template

Quick Start & Documentation

microfrontends

microservices

core library

Running unit tests

Run ng test my-app to execute the unit tests via Jest.

Run nx affected:test to execute the unit tests affected by a change.

Running end-to-end tests

Run ng e2e my-app to execute the end-to-end tests via Cypress.

Run nx affected:e2e to execute the end-to-end tests affected by a change.

Create tag

$ git commit
$ git commit -m '[upd] version ...;'
$ git tag v...
$ git commit -m '[upd] version ...;'
$ git push --tag
$ git push

Angular

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Pure pipes

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Pure it means that pipe don't mutation input date (without side effects)

OnPush + pure pipes

Strategy to OnPush. This means that change detection inside the Component will now be
triggered only when its @Input properties change.
We create a pure custom pipe to perform the required calculation only when the
pipe’s input changes. Uses the pipe instead of calling the method into templates of components.

Pure Pipes + Memoization

If pipe is pure we can cache the calculations instead of recalculating them @memo()

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Composite component

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использование переменной для из директивы для вызова различного функционала

    <div *carousel="let url from images; let ctrl = controller"> 
        <button (click)="ctrl.next()">

    const context = {
        $implicit: null ,
        controller: {
          next: () => this.next() // next: this.next.bind(this, param);
        }
    }

получение host component в директиве

// дочерняя директива/компонент совершенно спокойно может получить инстанс родителя через DI
import { Directive } from "@angular/core"; import { CountComponent } from "./count.component";

@Directive({ selector: "[increment]" })
export class IncrementDirective {
  constructor(private countComponent: CountComponent) {
    this.countComponent.count += 1;
  }
}

использование ngTemplateOutlet для проекции контента

    <div class="content">
      <ng-container
        [ngTemplateOutlet]="itemTemplateRef"
        [ngTemplateOutletContext]="{ $implicit: item, method1: myMethod }" ><!-- переменная, которая передается в шаблон -->
      </ng-container>
    </div>

    <!-- использование с передачей компонента внутри ng-template -->
    <app-container>
          <ng-template #itemTemplate let-item let-method="method1"> <!-- переменная полученная шаблоном -->
            <app-other-component [inputProp]="item"></app-other-component>
          </ng-template>
    </app-container>

import { ContentChild, TemplateRef } from '@angular/core'
// selector: 'app-container'
// ...
@ContentChild('itemTemplate', { static: false }) item: TemplateRef<any>;

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Interaction directives

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<div class="container" *context="let method = method">
    <ngn [context]="{method}"> </ngn>
    <button
        fireDirective
        (outputEvent)="method($event)">
        <!-- outputEvent: EventEmitter<Facade>
            fireDirective.HostListener.clickOrAnyEvent() => outputEvent.emit(facade);
            ...
            contextDirective.method(event) => event is Facade; // true
        -->
        Ok
    </button>
</div>

// InjectToken
import { InjectionToken, ContentChild, Inject, NgModule, Component } from '@angular/core';

type OrderAction;
export const ORDER_ACTION = new InjectionToken<OrderAction>('OrderAction');

class Service {
    public constructor(@Inject(ORDER_ACTION) private orderAction: OrderAction) {}
}

export const OTHER_ACTION: OrderAction = {/*... */};

@NgModule({
    providers: [{ provide: ORDER_ACTION, useValue: OTHER_ACTION }]
  })

export class AppModule {}

@Component({
  providers: [
    {
      provide: ORDER_ACTION,
      useExisting: CComponent,
    },
  ],
})
class CComponent implements OrderAction { 
    @ContentChild(ORDER_ACTION, { static: true }) orderAction: "OrderAction"; // this OTHER_ACTION for AppModule
}

import { Directive, Inject} from "@angular/core"; 

abstract class  AbstractTuiTableFilter<T, K> {}

///..

@Directive({
    selector: `[tuiGenericFilter]`,
    providers: [
        {
            provide: AbstractTuiTableFilter,
            useExisting: TuiGenericFilterDirective,
        },
    ],
})
class TuiGenericFilterDirective<T> {}

///...
class ComponentWithDirective<T> {
    constructor(@Inject(AbstractTuiTableFilter)private delegate: AbstractTuiTableFilter<T[keyof T], any>) { }
}

Extends Model and templated transform method of pipe

import { inject,Pipe,PipeTransform } from '@angular/core'; import { Observable} from 'rxjs';

@Pipe({ name: 'filterUsers', pure: true, standalone: true })
export class FilterUsersPipe implements PipeTransform {
    private filter = inject(FILTER_USERS_PIPE);
    transform<T extends User>(value: Observable<T[]>): Observable<T[]> {
        return this.filter(value) as Observable<T[]>;
    }
}
`<ng-container *http="let hotTabs; get: url; typeof: ExUser">
    <ng-container *ngFor="let tabContent of hotTabs | filterUsers | async">` // tabContent is ExUser

`<ng-template [ngTemplateContextGuard]="guardFn" let-article>`

export class FooComponent {
    public readonly guardFn = (ctx: any): ctx is Context<Article> => true;
}

async next observable

import { ReplaySubject} from 'rxjs';

const editor$ = new ReplaySubject<typeof Editor>(1);

// eslint-disable-next-line @typescript-eslint/no-floating-promises
import(`@tiptap/core`).then(m => editor$.next(m.Editor));

using (runOutsideAngular)

1. addEventListener
2. removeEventListener

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How to mock backend response

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1. HttpInterceptor gives you more freedom regarding mocking data from external libraries

2. JSON server is a JavaScript library for mocking REST APIs. $ npm install json-server

3. Cookies write a script for your middleware (e.g. APIC) that checks for specific cookies e.g.
   errorapi, errorcode and errorbody.

4. JSON generators

   • auto mocker-data-generator, json-generator.com
   • manual faker.js

ES LINTER

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rules

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1. [rx] don't use *ngIf (don't create inside variable | async as variable)
2. [naming] use 'create' prefix for method except for only methods using inside inject
   

   create...() { let value = { prop: inject(TOKEN)}}

3. [naming] don't use redundant 'postfix' entity name:
   

   StrategyScroll -> dispatcherScroll (incorrect)
   StrategyScroll -> dispatcher (correct)

4. [naming] method interactions:
   

   internal methods have short name without postfix of main type
   external methods have this is postfix

5. [dci] create roles(methods):
   

   if method takes parameters it must returns UnaryFunction for pipe
   

6. [dci] data:
   

   all utilities instead of the returned result should set value to same named property of ChangesType<T>
   

7. [dci] encapsulation:
   

   add data for encapsulate in object that pass to tube(...)({ overlay, encapsulateObject})
   this avoids enriching the object whose data must be returned from the method