def _import_module(mod_str): try: if mod_str.startswith('bin.'): imp.load_source(mod_str[4:], os.path.join('bin', mod_str[4:])) return sys.modules[mod_str[4:]] else: return importutils.import_module(mod_str) except Exception as e: sys.stderr.write("Error importing module %s: %s\n" % (mod_str, str(e))) return None
def __get_backend(self): """Get the actual backend. May be a module or an instance of a class. Doesn't matter to us. We do this synchronized as it's possible multiple greenthreads started very quickly trying to do DB calls and eventlet can switch threads before self.__backend gets assigned. """ if self.__backend: # Another thread assigned it return self.__backend backend_name = CONF.database.backend self.__use_tpool = CONF.database.use_tpool if self.__use_tpool: from eventlet import tpool self.__tpool = tpool # Import the untranslated name if we don't have a # mapping. backend_path = self.__backend_mapping.get(backend_name, backend_name) backend_mod = importutils.import_module(backend_path) self.__backend = backend_mod.get_backend() return self.__backend