tomastrajan

export function cancelable() : MethodDecorator {

  return function ( target : any, propertyKey : string, descriptor : PropertyDescriptor ) {
  
    const originalFn = descriptor.value;
    const subject = new BehaviorSubject(undefined);
    const result$ = subject.asObservable().switchMap(args => originalFn(...args));
    
    descriptor.value = (...args) => {
      subject.next(args);

tomastrajan

export class AuthApplicationService {

  // inject all needed services  
  constructor(
    private sessionService: SessionService,
    private authService: AuthService
  ) {}

  // orchestrate multi service execution
  // note that subscription and cancelation are responsibility of the caller

tomastrajan

@Injectable()
export class TodosService {

  private model: Model<Todo[]>;

  todos$: Observable<Todo[]>;

  constructor(private modelFactory: ModelFactory<Todo[]>) {
    this.model = this.modelFactory.create([]);
    this.todos$ = this.model.data$;

tomastrajan

import { NgModule } from '@angular/core';
import { MODEL_PROVIDER } from './model.service';

@NgModule({
  /* ... */
  providers: [MODEL_PROVIDER]
})
export class CoreModule { }

tomastrajan

/* route configuration */ 
const routes: Routes = [
  {
    path: 'todos',
    component: TodosComponent,
    resolve: {
      todosInitialized: TodosService
    }
  }
  /* ... */

tomastrajan

  /* session and clients models in some component or service */
    
  const filteredClients$ = this.sessionService.session$
    .combineLatest(this.clientService.clients$)
    .map(([session, clients]) => clients.filter(client => {
       if (client.vip && session.accessVips) {
         return true;
       } else if (!client.vip) {
         return true;
       } 

tomastrajan

@Component({
  selector: 'todos',
  template: `
    <!-- 
       accessing multiple properties, 
       we're better off subscribing only once in component's ngOnInit()
    -->
    Done todos: {{count.done}}
    Remaining todos: {{count.remaining}}
    All todos: {{count.all}}

tomastrajan

export class TodosComponent {
  
  /* ... */ 

  onTodoToggleClick(todo: Todo) {
    this.todosService.toggleTodo(todo.name);
  }

}

tomastrajan

@Injectable()
export class TodosService {

  /* ... */
    
  // pass all neccessary data as funcion parameters 
  toggleTodo(name: string) {

    // retrieve model internal state
    const todos = this.model.get();