XMLHttpRequest - limitation receiving data asynchronously

[BjoernK]

Hello everybody.

I'm developing a mobile QtQuick app but I encountered a general problem with the XMLHttpRequest-object:
The app communicates with a server via a JSON API (sending JSON objects and receiving JSON objects as response).
I use the XMLHttpRequest for asynchronous requests. There is one API call that makes the server respond with a JSON object which contains about ~500 data records (< 40 kilobytes). I can't manage to receive this response object. I checked that the server sends valid JSON data.
Do I have to modify the HTTP headers for the app's requests?
The mentioned response object is received successfully when the app requests the data synchronously.

I shortened the JavaScript-method which I use to request data. The second parameter of the function is supposed to be a function to allow processing of the received data.

function test(jsonRequest, callBack)
{
    var http = new XMLHttpRequest()
    var url = "http://example.com"
    var async = true
    http.open("POST", url, async)
    // send the proper header information along with the request
    http.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
    http.setRequestHeader("Content-length", jsonRequest.length)
    http.setRequestHeader("Connection", "Close")
    http.onreadystatechange = function()
    {
        if (http.readyState === XMLHttpRequest.DONE)
        {
            if (http.status === 200)
            {
                var jsonResponse = http.responseText
                try
                {
                    if (jsonResponse == "")
                    {
                        throw "API-Error"
                    }
                    var jsonResponseObject = JSON.parse(jsonResponse)
                    if (typeof(callBack) == "function")
                        callBack(jsonResponseObject)
                    else
                        throw "no callBack-function specified: type of callBack: " + typeof(callBack)
                }
                catch(e)
                {
                    if (Qt.platform.os == "windows")
                        console.log("\n\n" + e + ":\njsonRequest: >" + jsonRequest + "<\njsonResponse: >" + jsonResponse + "<\n")
                }
            }
        }
    }
    http.send(jsonRequest)
}

Thank you for reading.

[raven-worx]

@BjoernK
such a feature is not part of the HTTP standard.
Is the server application under your control? If so you need to add a custom parameter to the request to define the response limit.

[BjoernK]

@raven-worx
Thank you for your answer.
The server is not directly under my control but I can send suggestions to the person in charge. I will suggest to modify the API so one can specify the desired amount of data records per call.