def __reduce__(self):
mod = self.__fn.__module__
name = self.__fn.__name__
try:
obj = load_back(mod, name)
except (ImportError, KeyError, AttributeError):
raise pickle.PicklingError(
"Can't pickle as_op(), not found as %s.%s" % (mod, name))
else:
if obj is not self:
raise pickle.PicklingError(
"Can't pickle as_op(), not the object "
"at %s.%s" % (mod, name))
return load_back, (mod, name)
def __getstate__(self):
"""
Return kwarg_dict dict
Part of over-riding default pickle/unpickle behavior
Raise exception if trying to pickle and active handler
"""
if self.active:
raise pickle.PicklingError("can not pickle active handler")
return self.kwarg_dict
def ensure_bytestream(obj):
"""
Converts an object into a bytestream.
If `obj` is file-like, its contents will be read into memory and then wrapped in a bytestream.
This has a performance cost, but checking beforehand whether an arbitrary file-like object
returns bytes rather than encoded characters is an implementation nightmare.
If `obj` is not file-like, it will be serialized and then wrapped in a bytestream.
Parameters
----------
obj : file-like or object
Object to convert into a bytestream.
Returns
-------
bytestream : file-like
Buffered bytestream of the serialized artifacts.
method : {"joblib", "cloudpickle", "pickle", None}
Serialization method used to produce the bytestream.
Raises
------
pickle.PicklingError
If `obj` cannot be serialized.
ValueError
If `obj` contains no data.
"""
if hasattr(obj, 'read'): # if `obj` is file-like
reset_stream(obj) # reset cursor to beginning in case user forgot
contents = obj.read() # read to cast into binary
reset_stream(obj) # reset cursor to beginning as a courtesy
if not len(contents):
raise ValueError("object contains no data")
bytestring = six.ensure_binary(contents)
bytestream = six.BytesIO(bytestring)
bytestream.seek(0)
return bytestream, None
else: # `obj` is not file-like
bytestream = six.BytesIO()
try:
cloudpickle.dump(obj, bytestream)
except pickle.PicklingError: # can't be handled by cloudpickle
pass
else:
bytestream.seek(0)
return bytestream, "cloudpickle"
try:
joblib.dump(obj, bytestream)
except (
NameError, # joblib not installed
pickle.PicklingError): # can't be handled by joblib
pass
else:
bytestream.seek(0)
return bytestream, "joblib"
try:
pickle.dump(obj, bytestream)
except pickle.PicklingError: # can't be handled by pickle
six.raise_from(
pickle.PicklingError("unable to serialize artifact"), None)
else:
bytestream.seek(0)
return bytestream, "pickle"
