Carrega Último Informativo

<iframe id="estanteiframe" height="850" style="width: 100%; margin: 0; padding: 0" frameborder="0" src=""> </iframe>


<script type="text/javascript">
let req = new XMLHttpRequest();
let publicServiceKey = 'CODIGODESUAESTANTE';
req.open('GET', 'https://www.businessinformativos.com.br/Services/Informativos/json?auth=' + publicServiceKey, true);
req.onload = function () {            
	if (req.status >= 200 && req.status < 400) {
		let jsonRev = JSON.parse(req.responseText); 
		document.querySelector('#estanteiframe').setAttribute("src",jsonRev.infos[0].hlink)
    console.log(jsonRev.infos[0].hlink);
	} else {
		alert('Erro ao carregar os informativos');
	}
}
req.send();

</script>