Angular 4, convert http response observable to object observable

Question

I\'m new to the concepts of observables and need some help with a conversion.
I have a service which returns an Observable from a Http request,

Answer 1

I guess your HTTP Response is a JSON containing a PriceTag? The issue is that you want to create a PriceTag object. You can just convert the json to a PriceTag by type casting, but then it won't be a real PriceTag object.

The way we have resolved this is:

export class Serializable {
  constructor(json?: any) {
    if (json) {
      Object.assign(this, json);
    }
  }
}

And then a serializable class:

export class PriceTag extends Serializable {}

Then, your GetPriceTags function needs to be changed to:

getPriceTags(): Observable {

    // Set the request headers
    const headers = new Headers({ 'Content-Type': 'application/json' });

    // Returns the request observable
    return this.http.post(Constants.WEBSERVICE_ADDRESS + "/priceTag", null, {headers: headers})
    .map(res => new PriceTag(res.json()));

}