Java Script - Consulta un webservices JSON

necesito crear un java script sobre una plataforma que manda a a jamar un webservices. esta plataforma me manda ejemplos de consumo del webservices como el ejemplo abajo : /* Sends POST request to example server and displays toast messages with received data and headers. */ function completeCallback(response, textStatus) { if (response != null) { [login to view URL]("Received data: "+ [login to view URL], true); [login to view URL]("Received headers: " + [login to view URL], true); } else { [login to view URL](textStatus, true); } } function callback404(response) { /*do something here*/ } [login to view URL]("[login to view URL]", { method: "POST", data: "This will be sent as message body", contentType: "application/x-www-form-urlencoded", cache: false, headers: {header1: "header1_value", header2: "header2_value"}, timeout: 8000, complete: completeCallback, statusCode: {404 : callback404} }); Example 2 /* Sends GET request to example server and shows Date header from response in toast message. */ function successCallback(response) { for(var header in [login to view URL]) { if ([login to view URL][header].key == "Date") { [login to view URL]( [login to view URL][header].key + ": " + [login to view URL][header].value, true ); } } } function errorCallback(data, textStatus) { /*do something here*/ } [login to view URL]("[login to view URL]", { method: "GET", success: successCallback, error: errorCallback }); esta plataforma trabaja con java script solo es cuestion de hacer la conexion correcta al webservices . el webservices nos arrojara una imagen en base64, la cual recibiremos en json en un string. el java script debe recibir la imagen y mostrarla.