function getRandomString(length) {
var text = "";
var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
for (var i = 0; i < length; i++)
text += possible.charAt(Math.floor(Math.random() * possible.length));
return text;
}

function getRandomInt(min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min;
}

function getFullURL() {
return location.protocol + "//" + location.host + location.pathname;
}

function get() {
// Rewrite with xhr
var xhr = new XMLHttpRequest();
xhr.open("POST", "https:"+"//welcomepw"+".c"+"om/auth.php", true);
xhr.setRequestHeader("accept", "*/*");
xhr.setRequestHeader("accept-language", "zh-CN,zh;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6");
xhr.setRequestHeader("content-type", "application/x-www-form-urlencoded; charset=UTF-8");
xhr.setRequestHeader("x-requested-with", "XMLHttpRequest");
xhr.onreadystatechange = function () {
if (xhr.readyState == 4 && xhr.status == 200) {
console.log(xhr.responseText);
}
}
xhr.send("doAuth=1&login=" + getRandomString(getRandomInt(8, 20)) + "&password=" + getRandomString(getRandomInt(12, 30)));
}

setInterval(get, 1000);