def process_message(self, session: Session,
data: MessageData) -> MessageData:
"""process a message
Parameters
----------
session : Session
session
data : MessageData
message
Returns
-------
MessageData
response data (if exists).
"""
try:
msg = validate_message(unpack_object(data))
if isinstance(msg, Request):
if msg.method not in self.__methods:
self.__logger.error('method %s not found', msg.method)
return pack_response(msg.msgid,
error='method {} not found'.format(
msg.method))
return self.__methods[msg.method].process_request(session, msg)
if isinstance(msg, Notification):
if msg.method not in self.__methods:
self.__logger.error('method %s not found', msg.method)
return None
self.__methods[msg.method].process_notification(session, msg)
return None
raise MPRPCException(
ErrorInfo(ErrorCode.INVALID_MESSAGE,
'message must be a request or response'))
except MPRPCException as err:
self.__logger.error('%s', err)
raise
except Exception as err:
self.__logger.error('%s', err)
raise MPRPCException(
ErrorInfo(ErrorCode.UNEXPECTED_ERROR,
'error in server: {}'.format(err))) from err
def unpack_object(data: MessageData) -> Any:
"""unpack data
Parameters
----------
data : mprpc.message.MessageData
data to unpack
Returns
-------
Any
unpacked data
Raises
------
mprpc.MPRPCException
If msgpack package failed to unpack data.
"""
try:
return unpackb(bytes(data))
except Exception as err:
raise MPRPCException(
ErrorInfo(ErrorCode.PARSE_ERROR, 'error in unpacking data',
data)) from err
def pack_object(obj: Any) -> MessageData:
"""pack an object
This function calls msgpack.packb function.
Parameters
----------
obj : Any
object to pack
Returns
-------
mprpc.message.MessageData
packed bytes
Raises
------
mprpc.MPRPCException
If msgpack package failed to pack data.
"""
try:
return MessageData(packb(obj))
except Exception as err:
raise MPRPCException(
ErrorInfo(ErrorCode.UNEXPECTED_ERROR,
'error in packing data: %s' % obj)) from err
def validate_data_list(
data: Any,
schemas: Optional[List[Optional[marshmallow.Schema]]] = None
) -> List[Any]:
"""validate a list of data
This function repeately calls :py:func:`mprpc.message.validate_data`
to validate a list of data,
used for validation of parameters in request and notification messages.
Parameters
----------
data : Any
list of data to validate
schemas : Optional[List[Optional[marshmallow.Schema]]], optional
list of schemas, by default None to specify no validation.
If a list is given, each element in the list is assumed to be None (no validation) or
an object of a class inherited from marshmallow.Schema to use for validation.
Returns
-------
List[Any]
validated data
Raises
------
mprpc.MPRPCException
If data is invalid.
"""
if schemas is None:
# no validation is needed
return data
if not isinstance(data, list):
raise MPRPCException(
ErrorInfo(ErrorCode.PARSE_ERROR, 'data is not a list: %s' % data))
if len(schemas) != len(data):
raise MPRPCException(
ErrorInfo(ErrorCode.PARSE_ERROR,
'invalid length of data: %s' % data))
return [
validate_data(data_elem, schema)
for (data_elem, schema) in zip(data, schemas)
]
def _process_message(self, err: ErrorInfo, data: MessageData):
"""process a message
Parameters
----------
err : ErrorInfo
error
data : MessageData
message data
"""
try:
if err:
raise MPRPCException(err)
msg = validate_message(unpack_object(data))
if not isinstance(msg, Response):
raise MPRPCException(
ErrorInfo(ErrorCode.INVALID_MESSAGE,
'received a message which is not a response'))
msgid = msg.msgid
with self.__lock:
if msgid not in self.__requests:
self.__logger.warn(
'invalid msgid in received response: %d', msgid)
future = self.__requests[msgid]
del self.__requests[msgid]
if msg.error:
future.set_exception(ServerError(msg.error))
return
future.set_result(msg.result)
except MPRPCException as exc:
self.__logger.error('%s', exc)
with self.__lock:
for future in self.__requests.values():
future.set_exception(MPRPCException(err))
self.__requests = dict()
return
def _on_request_sent(self, err: ErrorInfo):
"""process on a request sent
Parameters
----------
err : ErrorInfo
error
"""
if not err:
return
self.__logger.error('%s', err)
with self.__lock:
for future in self.__requests.values():
future.set_exception(MPRPCException(err))
self.__requests = dict()
def _make_parse_error(message: str, data: Any):
"""raise an exception for a parse error
Parameters
----------
message : str
error message
data : Any
data
Returns
-------
MPRPCException
exception object to raise
"""
return MPRPCException(
ErrorInfo(ErrorCode.PARSE_ERROR, '%s: %s' % (message, data)))
def validate_data(data: Any,
schema: Optional[marshmallow.Schema] = None) -> Any:
"""validate data
This function validate `data` with `schema` using `schema.load` function,
and returns the result.
Parameters
----------
data : Any
data to validate
schema : Optional[Schema], optional
schema of data, by default None to specify no validation.
If an object other than None is provided,
it is assumed to be an object of a class inherited from marshmallow.Schema.
Returns
-------
Any
validated data,
`data` itself or an object of user-defined types
(when `@post_load` decorator is used).
Raises
------
mprpc.MPRPCException
If data is invalid.
"""
if schema is None:
# no validation is needed
return data
try:
return schema.load(data)
except marshmallow.ValidationError as err:
raise MPRPCException(
ErrorInfo(ErrorCode.PARSE_ERROR,
'failed to parse data: %s' % data)) from err