Retun data from a Django view after a javascript AJAX POST request

I am using Javascript to send an asynchronous request to a Django View. The View is able to receive data from the POST request, but I can’t seem to return a message to confirm that everything worked. I was expecting that xhttp.responseText would contain the message Thankyou, but it is empty.

The html part looks like this:

<textarea id="message"></textarea>
<input type="submit" value="Send" id="send_button onclick="submit_message()"/>

The javascript looks like this:

function submit_message(){
    document.getElementById("send_button").value="Sent - Thankyou!";
    message = document.getElementById("message").value

    var xhttp = new XMLHttpRequest();

    xhttp.open("POST", "/send-message");
    xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    xhttp.send("csrfmiddlewaretoken={{ csrf_token }}&message="+message);

    console.log('Sent POST request')
    console.log(xhttp.responseText)
}

I was hoping that xhttp.responseText would print Thankyou to the console.

The Django View function looks like this:

def send_message(request):
    message = request.POST.get('message')
    print(message)
    return HttpResponse('Thankyou')

The message variable prints out as expected, but Thankyou doesn’t seem to be returned.

I am doing AJAX with JS for the first time, so I expect I’ve just misunderstood something simple.

— EDIT — I have it working, after following the suggestion and reading this https://developer.mozilla.org/en-US/docs/Web/Guide/AJAX/Getting_Started

After the line xhttp.send(… I have this function

xhttp.onreadystatechange = function handle_response(){
    if (xhttp.readyState === XMLHttpRequest.DONE) {
        // Everything is good, the response was received.
        console.log('Things are good')
        console.log(xhttp)
        console.log(xhttp.response)
    } else {
        // Not ready yet.
        console.log('Not ready')
    }
}

It wasn’t necessary to use JsonResponse, but I will give that a try as well.

Answer

I can only recommend to you, the usage of JsonResponse instead of HttpResponse for confirm your submit. Your problem I presume it is in JS, you need to confirm the server response, check this article for better understand of ajax requests https://developer.mozilla.org/es/docs/Web/Guide/AJAX/Getting_Started#segundo_paso_.e2.80.93_procesando_la_respuesta_del_servidor

if (xhttp.readyState == 4) {
    // response received
    console.log(xhttp.responseText)
} else {
    // server not ready yet
    console.log("Server not ready")
}