core.py 文件源码

def _load_plugin_class(self, filepath):
        """
        Loads the plugin method and sets the self.plugin to refer to it.
        :param filepath: path to the file containing the python function
        """
        expected_class = 'ObservationUpdater'

        mod_name, file_ext = os.path.splitext(os.path.split(filepath)[-1])

        if file_ext.lower() == '.pyc':
            py_mod = imp.load_compiled(mod_name, filepath)
        else:
            py_mod = imp.load_source(mod_name, filepath)

        if hasattr(py_mod, expected_class):
            self.plugin = getattr(py_mod, expected_class)()
        else:
            raise Exception(
                'Cannot find ObservationUpdater class in pluging file ' +
                filepath)

        if not hasattr(self.plugin, 'update'):
            raise Exception(
                'Cannot find update method in plugin class ' + filepath)