def deserialize_msg(msg): # NOTE(russellb): Hang on to your hats, this road is about to # get a little bumpy. # # Robustness Principle: # "Be strict in what you send, liberal in what you accept." # # At this point we have to do a bit of guessing about what it # is we just received. Here is the set of possibilities: # # 1) We received a dict. This could be 2 things: # # a) Inspect it to see if it looks like a standard message envelope. # If so, great! # # b) If it doesn't look like a standard message envelope, it could either # be a notification, or a message from before we added a message # envelope (referred to as version 1.0). # Just return the message as-is. # # 2) It's any other non-dict type. Just return it and hope for the best. # This case covers return values from rpc.call() from before message # envelopes were used. (messages to call a method were always a dict) if not isinstance(msg, dict): # See #2 above. return msg base_envelope_keys = (_VERSION_KEY, _MESSAGE_KEY) if not all(map(lambda key: key in msg, base_envelope_keys)): # See #1.b above. return msg # At this point we think we have the message envelope # format we were expecting. (#1.a above) if not version_is_compatible(_RPC_ENVELOPE_VERSION, msg[_VERSION_KEY]): raise UnsupportedRpcEnvelopeVersion(version=msg[_VERSION_KEY]) raw_msg = jsonutils.loads(msg[_MESSAGE_KEY]) return raw_msg
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('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", (ex_type,), {'__str__': str_override, '__unicode__': str_override}) 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
def _deserialize(data): """ Deserialization wrapper """ LOG.debug(_("Deserializing: %s"), data) return jsonutils.loads(data)
def _from_json(self, datastring): try: return jsonutils.loads(datastring) except ValueError: msg = _("cannot understand JSON") raise exception.MalformedRequestBody(reason=msg)