Memory leak on each http request

[delacko]

I made a simple qml file with a timer that generates a HTTP GET request every 10 ms.
This causes memory leak at a rate of approximately 30-40 kB / second.

A smaller l

eak also exists if interval between requests is larger - ie. 200 ms request interval - leak seems proportional to number of requests.

Leak does not depend on the size of HTTP GET response. I tested with response of approximately 10 bytes, 100 kB, 10 MB.

Test environment: Linux Desktop, Qt 5.15.0

Sample:

import QtQuick 2.15
import QtQuick.Window 2.15
import com.cutehacks.duperagent 1.0 as Http

Window {
    id: window
    visible: true
    width: 640
    height: 480
    property int idx: 0
    Timer
    {
        id: requestTimer
        interval: 50
        repeat: true
        triggeredOnStart: true
        running: true
        onTriggered:
        {
            request(idx++)
            gc()
        }
    }
    Component.onCompleted:
    {
        Http.Request.config({
               cache: false
           });
    }
    function request(reqIdx){
            console.log("request initiated "+ reqIdx)

        var url = "http://localhost:9001/Screenshot_20200620_101301.png"
        Http.Request
        .get(url)
        .timeout(5000)
        .end(function(err, res) {
            console.log("request finished "+ reqIdx)
        });
    }
}

[mohammadhasanzadeh]

Hi, I think the reason for the memory leak on every request comes from the allocation of RequestPrototype instance, for example, you can see line #38 on duperagent.cpp:

QJSValue Request::get(const QJSValue &url, const QJSValue &data, const QJSValue &fn) const
{
    RequestPrototype *proto = new RequestPrototype(
                m_engine,
                RequestPrototype::Get,
                QUrl(url.toString()));

    if (data.isCallable()) {
        proto->end(data);
    } else if (!data.isUndefined()){
        proto->query(data);
    }

    if (fn.isCallable()) {
        proto->end(fn);
    }

    return proto->self();
}

it seems proto will never deleted.