class FileDownloader(): """The blueprint for downloading file from url.""" def __init__(self, url, output_path, progress_dialog=None): """Constructor of the class. .. versionchanged:: 3.3 removed manager parameter. :param url: URL of file. :type url: str :param output_path: Output path. :type output_path: str :param progress_dialog: Progress dialog widget. :type progress_dialog: QWidget """ # noinspection PyArgumentList self.manager = QgsNetworkAccessManager.instance() self.url = QUrl(url) self.output_path = output_path self.progress_dialog = progress_dialog if self.progress_dialog: self.prefix_text = self.progress_dialog.labelText() self.output_file = None self.reply = None self.downloaded_file_buffer = None self.finished_flag = 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()) # Prepare downloaded buffer self.downloaded_file_buffer = QByteArray() # Request the url request = QNetworkRequest(self.url) self.reply = self.manager.get(request) self.reply.readyRead.connect(self.get_buffer) self.reply.finished.connect(self.write_data) self.manager.requestTimedOut.connect(self.request_timeout) 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 QgsApplication.processEvents() self.progress_dialog.adjustSize() human_received = humanize_file_size(received) human_total = humanize_file_size(total) label_text = tr("%s : %s of %s" % ( self.prefix_text, human_received, human_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.deleteLater() 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 # returns False even after finished slot is called. So, that's why we # are adding self.finished_flag (see #864) while not self.reply.isFinished() and not self.finished_flag: # noinspection PyArgumentList QgsApplication.processEvents() result = self.reply.error() try: http_code = int(self.reply.attribute( QNetworkRequest.HttpStatusCodeAttribute)) except TypeError: # If the user cancels the request, the HTTP response will be None. http_code = None self.reply.abort() self.reply.deleteLater() if result == QNetworkReply.NoError: return True, None elif result == QNetworkReply.UnknownNetworkError: return False, tr( 'The network is unreachable. Please check your internet ' 'connection.') elif http_code == 408: msg = tr( 'Sorry, the server aborted your request. ' 'Please try a smaller area.') LOGGER.debug(msg) return False, msg elif http_code == 509: msg = tr( 'Sorry, the server is currently busy with another request. ' 'Please try again in a few minutes.') LOGGER.debug(msg) return False, msg elif result == QNetworkReply.ProtocolUnknownError or \ result == QNetworkReply.HostNotFoundError: # See http://doc.qt.io/qt-5/qurl-obsolete.html#encodedHost encoded_host = self.url.toAce(self.url.host()) LOGGER.exception('Host not found : %s' % encoded_host) return False, tr( 'Sorry, the server is unreachable. Please try again later.') elif result == QNetworkReply.ContentNotFoundError: LOGGER.exception('Path not found : %s' % self.url.path()) return False, tr('Sorry, the layer was not found on the server.') else: return result, self.reply.errorString() def get_buffer(self): """Get buffer from self.reply and store it to our buffer container.""" 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.finished_flag = True def request_timeout(self): """The request timed out.""" if self.progress_dialog: self.progress_dialog.hide()
class FileDownloader(): """The blueprint for downloading file from url.""" def __init__(self, url, output_path, progress_dialog=None): """Constructor of the class. .. versionchanged:: 3.3 removed manager parameter. :param url: URL of file. :type url: str :param output_path: Output path. :type output_path: str :param progress_dialog: Progress dialog widget. :type progress_dialog: QWidget """ # noinspection PyArgumentList self.manager = QgsNetworkAccessManager.instance() self.url = QUrl(url) self.output_path = output_path self.progress_dialog = progress_dialog if self.progress_dialog: self.prefix_text = self.progress_dialog.labelText() self.output_file = None self.reply = None self.downloaded_file_buffer = None self.finished_flag = 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()) # Prepare downloaded buffer self.downloaded_file_buffer = QByteArray() # Request the url request = QNetworkRequest(self.url) self.reply = self.manager.get(request) self.reply.readyRead.connect(self.get_buffer) self.reply.finished.connect(self.write_data) self.manager.requestTimedOut.connect(self.request_timeout) 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 QgsApplication.processEvents() self.progress_dialog.adjustSize() human_received = humanize_file_size(received) human_total = humanize_file_size(total) label_text = tr( "%s : %s of %s" % (self.prefix_text, human_received, human_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.deleteLater() 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 # returns False even after finished slot is called. So, that's why we # are adding self.finished_flag (see #864) while not self.reply.isFinished() and not self.finished_flag: # noinspection PyArgumentList QgsApplication.processEvents() result = self.reply.error() try: http_code = int( self.reply.attribute(QNetworkRequest.HttpStatusCodeAttribute)) except TypeError: # If the user cancels the request, the HTTP response will be None. http_code = None self.reply.abort() self.reply.deleteLater() if result == QNetworkReply.NoError: return True, None elif result == QNetworkReply.UnknownNetworkError: return False, tr( 'The network is unreachable. Please check your internet ' 'connection.') elif http_code == 408: msg = tr('Sorry, the server aborted your request. ' 'Please try a smaller area.') LOGGER.debug(msg) return False, msg elif http_code == 509: msg = tr( 'Sorry, the server is currently busy with another request. ' 'Please try again in a few minutes.') LOGGER.debug(msg) return False, msg elif result == QNetworkReply.ProtocolUnknownError or \ result == QNetworkReply.HostNotFoundError: # See http://doc.qt.io/qt-5/qurl-obsolete.html#encodedHost encoded_host = self.url.toAce(self.url.host()) LOGGER.exception('Host not found : %s' % encoded_host) return False, tr( 'Sorry, the server is unreachable. Please try again later.') elif result == QNetworkReply.ContentNotFoundError: LOGGER.exception('Path not found : %s' % self.url.path()) return False, tr('Sorry, the layer was not found on the server.') else: return result, self.reply.errorString() def get_buffer(self): """Get buffer from self.reply and store it to our buffer container.""" 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.finished_flag = True def request_timeout(self): """The request timed out.""" if self.progress_dialog: self.progress_dialog.hide()