export class stru {

"date": string;
"items": string;

    }

getstru(): Observable<stru[]> {
    return this.http
    .get(
      API_URL + "stru/"
    )
    .pipe(map((response: Response) => < stru[] > response.json()));
}

this.Service.getstru().subscribe(res => {
      this.test= res;
      this.ledger= this.test;
      this.sortedflt=this.ledger.filter(task => task.items === "item1");
      console.log("filteres",this.sortedflt);
  })