I'm looking to enhance an existing angular service (for example, Http).
Requirements:
- The extension of the service should be done through angular's dependency injection
- It should be possible to extend the service multiple times using a pattern similar to the Decorator Pattern
- The resulting object should implement or extend the functionality of the
Httpservice so that existing code remains compatible. The dependency injector should inject the "decorated"Http. - A potential use case could involve an instance of
Httpembellished withSecureHttpandLoggingHttp.
What I've tried so far:
SecureHttp implements Httpdidn't work because 1.Httpis not an interface and 2. it has protected members that require implementation.To extend
Http:class SecureHttp extends Http { constructor(_backend: ConnectionBackend, _defaultOptions: RequestOptions, private _http: Http){ super(_backend, _defaultOptions); } get(url: string, options?: RequestOptionsArgs): Observable<Response> { console.log("This is secure Http."); return this._http.get(url, options); } ... }I'm unsure how to set up the service so that
Httpis injected into theSecureHttpclass whileHttpinSecureHttpalso gets injected byHttp.
Am I on the right path?
Alternatively, are there other angular2 concepts that facilitate extending existing services that I may not be aware of?