angular-aems v0.0.5

AngularAems

This is an experimental implementation of an API Entity Management Service for Angular.

Install

Run yarn add angular-aems in your project root.

Usage

Step 1

Import AngularAemsModule in your app.

import { AngularAemsModule } from 'angular-aems';

@NgModule({
  imports: [
    AngularAemsModule
  ]
})
export class AppModule {
}

Step 2

Inject EntityService into your component and set the apiBaseUrl.

import { Component, OnInit } from '@angular/core';

import { EntityService } from 'angular-aems';

import { Event } from './_interfaces/event.interface';

@Component({
  selector: 'app-root',
  template: `<h2>Events</h2>
  <ul>
    <li *ngFor="let event of events">{{ event.title }}</li>
  </ul>`
})
export class AppComponent implements OnInit {
  events: Event[];

  constructor(
    private eventService: EntityService<Event>
  ) {
    eventService.config = {
      apiBaseUrl: 'events'
    };
  }

  ngOnInit() {
    this.eventService.getAll().subscribe(events => this.events = events);
  }
}

API

Service types

There are three kinds of services to help getting the job done.

• Service
• Transformer
• Resource

Service

The Service is the only "public" service you want to use directly in your code. Methods exists for read, write, update and delete one or more items.

If you extend the EntityService, the following methods are available:

  /**
   * Set configuration for this instance
   * @param config Object of type EntityConfig.
   */
  setConfig(config: EntityConfig): void {
    this.config = config;
  }

  /**
   * Get one item.
   * @param id Id of the item you want to get.
   */
  getOne(id: number): Observable<T> {
    return this.resource.getOne(id, this.config.apiBaseUrl).pipe(
      map((entity: T) => this.transformer.backendToFrontend(entity))
    );
  }

  /**
   * Get all items
   */
  getAll(): Observable<T[]> {
    return this.resource.getAll(this.config.apiBaseUrl).pipe(
      map((entities: T[]) => entities.map(x => this.transformer.backendToFrontend(x)))
    );
  }

Transformer

The Transformer is the service, which is internally used to transform the data from the frontend interface (used in our application) with the backend interface (provided by the rest endpoint).

Resource

The Resource is the part of the concept, which talks to the backend.