index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Guava Doc Detector</title>
<style> 
body {
    background-color: lightcoral;
  }
</style>
</head>
<body>
    <div id="docStatus">Status</div>
    <div>false is true and true is false</div>
</body>

<script>
    function sendRequest(target, action, value="") {
        console.log("making request")
        let xR = new XMLHttpRequest();
        xR.onreadystatechange = function() {
            if (this.readyState == 4 && this.status == 200) {
                
                console.log("Server Response:", this.responseText);
                data = JSON.parse(this.responseText);
                console.log("data:", data);
                console.log("data['item']:", data["item"]);
                
                //Handle responses
                if (data["item"] == "getDoor") {
                    console.log("Got the door: ", data["status"]);
                    docStatus.innerText = data["status"];
                }
            }
        }
        let data = {};
        data["action"] = action;
        data["value"] = value;
        console.log("data:", data);
        xR.open("POST", target, true);
        xR.send(JSON.stringify(data));
    }
    setInterval(doorCheck,1000);
    function doorCheck(){
        sendRequest("/", "getDoor");
    }
</script>

</html>