Improved fix temp

gistfile1.txt

class Downloader(object):
    """The blueprint for downloading file from url."""
    def __init__(self, manager, url, output_path, progress_dialog=None):
        self.manager = manager
        self.url = url
        self.output_path = output_path
        self.progress_dialog = progress_dialog
        self.reply = None
        self.output_file = None
        self.downloaded_file_buffer = QByteArray()
        self.is_finish = False

    def download(self):
        """Downloading the file.

        :returns: True if success, otherwise returns a tuple with format like
        this (QNetworkReply.NetworkError, error_message)

        :raises: IOError - when cannot create output_path
        """
        # Prepare output path
        self.output_file = QFile(self.output_path)
        if not self.output_file.open(QFile.WriteOnly):
            raise IOError(self.output_file.errorString())

        # Request the url
        request = QNetworkRequest(QUrl(self.url))
        self.reply = self.manager.get(request)
        self.reply.readyRead.connect(self.get_buffer)
        self.reply.finished.connect(self.write_data)

        if self.progress_dialog:
            # progress bar
            def progress_event(received, total):
                """Update progress.

                :param received: Data received so far.
                :type received: int
                :param total: Total expected data.
                :type total: int
                """
                # noinspection PyArgumentList
                QCoreApplication.processEvents()

                label_text = "%s / %s" % (received, total)
                self.progress_dialog.setLabelText(label_text)
                self.progress_dialog.setMaximum(total)
                self.progress_dialog.setValue(received)

            # cancel
            def cancel_action():
                """Cancel download."""
                self.reply.abort()

            self.reply.downloadProgress.connect(progress_event)
            self.progress_dialog.canceled.connect(cancel_action)

        # Wait until finished
        # On Windows 32bit AND QGIS 2.2, self.reply.isFinished() always
        # return False even after finished slot is called. So, that's why we
        # are adding self.is_finish (see #864)
        while not self.reply.isFinished() and not self.is_finish:
            # noinspection PyArgumentList
            QCoreApplication.processEvents()

        result = self.reply.error()
        if result == QNetworkReply.NoError:
            return True, None
        else:
            return result, str(self.reply.errorString())

    def get_buffer(self):
        """Get buffer from self.reply and store it to our buffer field."""
        buffer_size = self.reply.size()
        data = self.reply.read(buffer_size)
        self.downloaded_file_buffer.append(data)

    def write_data(self):
        """Write data to a file."""
        self.output_file.write(self.downloaded_file_buffer)
        self.output_file.close()
        self.is_finish = True


def download_url(manager, url, output_path, progress_dialog=None):
    """Download file from url.

    :param manager: A QNetworkAccessManager instance
    :type manager: QNetworkAccessManager

    :param url: URL of file
    :type url: str

    :param output_path: Output path
    :type output_path: str

    :param progress_dialog: Progress dialog widget
    """
    downloader = Downloader(manager, url, output_path, progress_dialog)
    try:
        result = downloader.download()
    except IOError as ex:
        raise IOError(ex)
    return result