Typescript generic service

You can create an abstract generic class and two children class that inherits from it :

abstract class:

export abstract class AbstractRestService<T> {
  constructor(protected _http: Http, protected actionUrl:string){
  }

  getAll():Observable<T[]> {
    return this._http.get(this.actionUrl).map(resp=>resp.json() as T[]);
  }
  getOne(id:number):Observable<T> {
    return this._http.get(`${this.actionUrl}${id}`).map(resp=>resp.json() as T);
  }
} 

driver service class

@Injectable()
export class DriverService extends AbstractRestService<Driver> {
  constructor(http:Http,configuration:Configuration){
    super(http,configuration.serverWithApiUrl+"Driver/");
  }
}

car service class

@Injectable()
export class CarService extends AbstractRestService<Car> {
  constructor(http:Http,configuration:Configuration) {
    super(http,configuration.serverWithApiUrl+"Car/");
  }
}

Note that only the concrete classes are marked as @Injectable() and should be declared inside a module while the abstract one should not.

update for Angular 4+

Http class being deprecated in favor of HttpClient, you can change the abstract class to something like that:

export abstract class AbstractRestService<T> {
  constructor(protected _http: HttpClient, protected actionUrl:string){
  }

  getAll():Observable<T[]> {
    return this._http.get(this.actionUrl) as Observable<T[]>;
  }

  getOne(id:number):Observable<T> {
    return this._http.get(`${this.actionUrl}${id}`) as Observable<T>;
  }
}