tractor/tractor/_exceptions.py

69 lines
1.6 KiB
Python

"""
Our classy exception set.
"""
import importlib
import builtins
import traceback
import trio
_this_mod = importlib.import_module(__name__)
class RemoteActorError(Exception):
# TODO: local recontruction of remote exception deats
"Remote actor exception bundled locally"
def __init__(self, message, type_str, **msgdata):
super().__init__(message)
for ns in [builtins, _this_mod, trio]:
try:
self.type = getattr(ns, type_str)
break
except AttributeError:
continue
else:
self.type = Exception
self.msgdata = msgdata
# TODO: a trio.MultiError.catch like context manager
# for catching underlying remote errors of a particular type
class InternalActorError(RemoteActorError):
"""Remote internal ``tractor`` error indicating
failure of some primitive or machinery.
"""
class NoResult(RuntimeError):
"No final result is expected for this actor"
class ModuleNotExposed(ModuleNotFoundError):
"The requested module is not exposed for RPC"
def pack_error(exc):
"""Create an "error message" for tranmission over
a channel (aka the wire).
"""
return {
'error': {
'tb_str': traceback.format_exc(),
'type_str': type(exc).__name__,
}
}
def unpack_error(msg, chan=None, err_type=RemoteActorError):
"""Unpack an 'error' message from the wire
into a local ``RemoteActorError``.
"""
tb_str = msg['error'].get('tb_str', '')
return err_type(
f"{chan.uid}\n" + tb_str,
**msg['error'],
)