Ejemplo n.º 1
0
def _get_impl():
    """Delay import of rpc_backend until configuration is loaded."""
    global _RPCIMPL
    if _RPCIMPL is None:
        try:
            _RPCIMPL = importutils.import_module(CONF.rpc_backend)
        except ImportError:
            # For backwards compatibility with older nova config.
            impl = CONF.rpc_backend.replace('nova.rpc',
                                            'nova.openstack.common.rpc')
            _RPCIMPL = importutils.import_module(impl)
    return _RPCIMPL
Ejemplo n.º 2
0
def deserialize_remote_exception(conf, data):
    failure = jsonutils.loads(str(data))

    trace = failure.get('tb', [])
    message = failure.get('message', "") + "\n" + "\n".join(trace)
    name = failure.get('class')
    module = failure.get('module')

    # NOTE(ameade): We DO NOT want to allow just any module to be imported, in
    # order to prevent arbitrary code execution.
    if module not in conf.allowed_rpc_exception_modules:
        return RemoteError(name, failure.get('message'), trace)

    try:
        mod = importutils.import_module(module)
        klass = getattr(mod, name)
        if not issubclass(klass, Exception):
            raise TypeError("Can only deserialize Exceptions")

        failure = klass(*failure.get('args', []), **failure.get('kwargs', {}))
    except (AttributeError, TypeError, ImportError):
        return RemoteError(name, failure.get('message'), trace)

    ex_type = type(failure)
    str_override = lambda self: message
    new_ex_type = type(ex_type.__name__ + _REMOTE_POSTFIX, (ex_type,),
                       {'__str__': str_override, '__unicode__': str_override})
    new_ex_type.__module__ = '%s%s' % (module, _REMOTE_POSTFIX)
    try:
        # NOTE(ameade): Dynamically create a new exception type and swap it in
        # as the new type for the exception. This only works on user defined
        # Exceptions and not core python exceptions. This is important because
        # we cannot necessarily change an exception message so we must override
        # the __str__ method.
        failure.__class__ = new_ex_type
    except TypeError:
        # NOTE(ameade): If a core exception then just add the traceback to the
        # first exception argument.
        failure.args = (message,) + failure.args[1:]
    return failure
Ejemplo n.º 3
0
Archivo: api.py Proyecto: Open-SFC/nscs
 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