Updating from Maemo skeleton

[gonvert] / src / util / qore_utils.py

diff --git a/src/util/qore_utils.py b/src/util/qore_utils.py
new file mode 100644 (file)
index 0000000..491c96d
--- /dev/null
+++ b/src/util/qore_utils.py
@@ -0,0 +1,107 @@
+import logging
+
+from PyQt4 import QtCore
+
+import misc
+
+
+_moduleLogger = logging.getLogger(__name__)
+
+
+class QThread44(QtCore.QThread):
+       """
+       This is to imitate QThread in Qt 4.4+ for when running on older version
+       See http://labs.trolltech.com/blogs/2010/06/17/youre-doing-it-wrong
+       (On Lucid I have Qt 4.7 and this is still an issue)
+       """
+
+       def __init__(self, parent = None):
+               QtCore.QThread.__init__(self, parent)
+
+       def run(self):
+               self.exec_()
+
+
+class _ParentThread(QtCore.QObject):
+
+       def __init__(self, pool):
+               QtCore.QObject.__init__(self)
+               self._pool = pool
+
+       @QtCore.pyqtSlot(object)
+       @misc.log_exception(_moduleLogger)
+       def _on_task_complete(self, taskResult):
+               on_success, on_error, isError, result = taskResult
+               if not self._pool._isRunning:
+                       if isError:
+                               _moduleLogger.error("Masking: %s" % (result, ))
+                       isError = True
+                       result = StopIteration("Cancelling all callbacks")
+               callback = on_success if not isError else on_error
+               try:
+                       callback(result)
+               except Exception:
+                       _moduleLogger.exception("Callback errored")
+
+
+class _WorkerThread(QtCore.QObject):
+
+       taskComplete  = QtCore.pyqtSignal(object)
+
+       def __init__(self, pool):
+               QtCore.QObject.__init__(self)
+               self._pool = pool
+
+       @QtCore.pyqtSlot(object)
+       @misc.log_exception(_moduleLogger)
+       def _on_task_added(self, task):
+               if not self._pool._isRunning:
+                       _moduleLogger.error("Dropping task")
+
+               func, args, kwds, on_success, on_error = task
+
+               try:
+                       result = func(*args, **kwds)
+                       isError = False
+               except Exception, e:
+                       _moduleLogger.error("Error, passing it back to the main thread")
+                       result = e
+                       isError = True
+
+               taskResult = on_success, on_error, isError, result
+               self.taskComplete.emit(taskResult)
+
+       @QtCore.pyqtSlot()
+       @misc.log_exception(_moduleLogger)
+       def _on_stop_requested(self):
+               self._pool._thread.quit()
+
+
+class AsyncPool(QtCore.QObject):
+
+       _addTask = QtCore.pyqtSignal(object)
+       _stopPool = QtCore.pyqtSignal()
+
+       def __init__(self):
+               QtCore.QObject.__init__(self)
+               self._thread = QThread44()
+               self._isRunning = True
+               self._parent = _ParentThread(self)
+               self._worker = _WorkerThread(self)
+               self._worker.moveToThread(self._thread)
+
+               self._addTask.connect(self._worker._on_task_added)
+               self._worker.taskComplete.connect(self._parent._on_task_complete)
+               self._stopPool.connect(self._worker._on_stop_requested)
+
+       def start(self):
+               self._thread.start()
+
+       def stop(self):
+               self._isRunning = False
+               self._stopPool.emit()
+
+       def add_task(self, func, args, kwds, on_success, on_error):
+               assert self._isRunning, "Task queue not started"
+               task = func, args, kwds, on_success, on_error
+               self._addTask.emit(task)