How to deal with http response type in angular?

Question

I write a http get request:

  getProduct(path, opts?): Observable<Product> {
    return this.http.get(path, opts?.httpParams).pipe(
      map((res:IProduct) => new Product(res))
    );
  }

My Product class construct with a Interface:

export Interface IProduct {
  productName:string;
  productCode:string;
  descr:string;
}

I thought when I assign a interface as type in map() , it will have a check about the content of the response. If it miss some property it will give me a error or something. But it doesn't, It just pass everything to try to instance a Product Object.

Am I missunderstanding about the usage of Interface? How can I ensure the response match the Interface or not?