Action links

@wizdm/actinlink enables Angular's Router to execture custom actions besides regular navigation tasks.

Installation

Use npm to install the @wizdm/actionlink module:

npm install @wizdm/actionlink

Usage

Import the ActionLinkObserver service and use it as a (CanActivate guard)[https://angular.io/api/router/CanActivate] within the routes you want to associate with your custom actions:

import { ActionLinkObserver } from '@wizdm/actionlink';
...
const routes: Routes = [

  { 
    path: 'home', component: HomeComponent, children: [
      ...
      // Custom action getting back to the previous page
      { path: 'back', canActivate: [ ActionLinkObserver ] },

  ]}
...
];

Use back as a regular link in your template.

...
  <a routerLink="back">Back</a>
...

Implement the custom action logic within your component or directive:

import { ActionLinkObserver } from '@wizdm/actionlink';
import { Location } from '@angular/common';
...
export class HomeComponent implements OnDestroy {

  private sub: Subscription;

  constructor(observer: ActionLinkObserver, location: Location) { 
    
    // Registers to the 'back' actionlink to navigate back on request
    this.sub = observer.register('back').subscribe( () => location.back() );
  }

  ngOnDestroy() { this.sub.unsubscribe(); }
}

Multiple actions can be implemented within the same component by registering the corresponding handles to their respective action codes. Custom observers for dedicated actions can also be implemented by extending the ActionLinkObserver and wrap the custom logic within it:

import { ActionLinkObserver } from '@wizdm/actionlink';
import { Location } from '@angular/common';
import { Router } from '@angular/router';
...
@Injectable({
  providedIn: 'root'
})
export class BackLinkObserver extends ActionLinkObserver implements OnDestroy {

  private sub: Subscription;

  constructor(location: Location, router: Router) { 
    
    super(router); 

    // Registers to the 'back' actionlink to navigate back on request
    this.sub = this.register('back').subscribe( () => location.back() );
  }

  ngOnDestroy() { this.sub.unsubscribe(); }
}

Use your custom observer instead of the ActionLinkObserver within your ROUTE to make it works.

How It Works

The ActionLinkObserver works as a CanActivate routing guard preventing the navigation and pushing the action through a ReplaySubject clients can subscribe to. Query Parameters are also packed into an object and passed along as a data payload for the client to act upon, when needed.