export interface Token {
    token: string
}

login (username: string, password: string): Observable<Token[]> {
      this.params = '?username=' + username + '&password=' + password;
      return this.http.post<Token[]>(this.loginURL + this.params, null, httpOptions).do(data => console.log(data));
  }

this.authService.login(this.username, this.password).subscribe(data => this.authService.token = data[0]);