QNetworkAccessManager Process Finished With Exit Code 139 (Interrupted by signal 11: SIGSEGV)

Question

Basically, I have 4 widgets in a QStackedWidget which are:

1. HomeWidget
2. ProcessWidget
3. ConfirmWidget
4. LoadingWidget

In ProcessWidget and LoadingWidget I will use QNetworkAccessManager to communicate with my API.

The flow of my application:

1. Begin with HomeWidget.

2. Then, switch to ProcessWidget.

3. Then, switch to ConfirmWidget.

4. Then, switch to LoadingWidget.

5. Then, switch back to HomeWidget and so on.

In ProcessWidget I only make 1 request. But in LoadingWidget I have 4 requests.

This is how I make the communication for each request (the difference of each request is the URL only):

def doRequest(self):
    url = "http://127.0.0.1:8000/api"
    req = QtNetwork.QNetworkRequest(QUrl(url))

    self.networkAccessManager = QtNetwork.QNetworkAccessManager()
    self.networkAccessManager.finished.connect(self.handleResponse)
    self.networkAccessManager.get(req)

def handleResponse(self, reply):

    er = reply.error()

    if er == QtNetwork.QNetworkReply.NoError:

        bytes_string = reply.readAll()
        data = json.loads(str(bytes_string, 'utf-8'))

        # Do something

    else:
        errorMessage = "Error occured: "+ str(er) + "\n"+ str(reply.errorString())
        # Do something

The problem is, on the 4th iteration of the flow process of my application, suddenly my application crash. It gives this error:

Process Finished With Exit Code 139 (Interrupted by signal 11: SIGSEGV)

What is the mistake?

Answer 1

Finally, I can solve the problem by redefining how I make the request.

This is the code:

# Instantiate the NetworkAccessManager as the Widget's property
self.networkAccessManager = QtNetwork.QNetworkAccessManager() 

def doRequest(self):
    url = "http://127.0.0.1:8000/api"
    req = QtNetwork.QNetworkRequest(QUrl(url))

    reply = self.networkAccessManager.get(req)
    reply.finished.connect(self.handleResponse)

def handleResponse(self):

    reply = self.sender()

    er = reply.error()

    if er == QtNetwork.QNetworkReply.NoError:

        bytes_string = reply.readAll()
        data = json.loads(str(bytes_string, 'utf-8'))

        # Do something

    else:
        errorMessage = "Error occured: "+ str(er) + "\n"+ str(reply.errorString())
        # Do something

    reply.deleteLater()

I can conclude that the problem come from the reply object.