def register(self, cls, handler):
"""Register the a custom handler for a class
:param cls: The custom object class to handle
:param handler: The custom handler class
"""
#GWV: this one will be used when pickling the class
name = util.importable_name(cls)
self._handlers[name] = handler
#GWV addition:
# this one will be used for unpickling: # also register as namespace:__name__
name = util.namespace_name(handler, cls)
#print 'Registry.register>', name
self._handlers[name] = handler
def _flatten_obj_instance(self, obj):
"""Recursively flatten an instance and return a json-friendly dict
"""
data = {}
has_class = hasattr(obj, '__class__')
has_dict = hasattr(obj, '__dict__')
has_slots = not has_dict and hasattr(obj, '__slots__')
has_getnewargs = hasattr(obj, '__getnewargs__')
has_getinitargs = hasattr(obj, '__getinitargs__')
has_reduce, has_reduce_ex = util.has_reduce(obj)
# Support objects with __getstate__(); this ensures that
# both __setstate__() and __getstate__() are implemented
has_getstate = hasattr(obj, '__getstate__')
if has_class:
cls = obj.__class__
else:
cls = type(obj)
# Check for a custom handler
class_name = util.importable_name(cls)
handler = handlers.get(class_name)
if handler is not None:
if self.unpicklable:
#GWV change
data[tags.OBJECT] = util.namespace_name(handler, cls)
return handler(self).flatten(obj, data)
reduce_val = None
if has_class and not util.is_module(obj):
if self.unpicklable:
class_name = util.importable_name(cls)
data[tags.OBJECT] = class_name
# test for a reduce implementation, and redirect before doing anything else
# if that is what reduce requests
if has_reduce_ex:
try:
# we're implementing protocol 2
reduce_val = obj.__reduce_ex__(2)
except TypeError:
# A lot of builtin types have a reduce which just raises a TypeError
# we ignore those
pass
if has_reduce and not reduce_val:
try:
reduce_val = obj.__reduce__()
except TypeError:
# A lot of builtin types have a reduce which just raises a TypeError
# we ignore those
pass
if reduce_val:
try:
# At this stage, we only handle the case where __reduce__ returns a string
# other reduce functionality is implemented further down
if isinstance(reduce_val, (str, unicode)):
varpath = iter(reduce_val.split('.'))
# curmod will be transformed by the loop into the value to pickle
curmod = sys.modules[next(varpath)]
for modname in varpath:
curmod = getattr(curmod, modname)
# replace obj with value retrieved
return self._flatten(curmod)
except KeyError:
# well, we can't do anything with that, so we ignore it
pass
if has_getnewargs:
data[tags.NEWARGS] = self._flatten(obj.__getnewargs__())
if has_getinitargs:
data[tags.INITARGS] = self._flatten(obj.__getinitargs__())
if has_getstate:
try:
state = obj.__getstate__()
except TypeError:
# Has getstate but it cannot be called, e.g. file descriptors
# in Python3
self._pickle_warning(obj)
return None
else:
return self._getstate(state, data)
if util.is_module(obj):
if self.unpicklable:
data[tags.REPR] = '%s/%s' % (obj.__name__,
obj.__name__)
else:
data = unicode(obj)
return data
if util.is_dictionary_subclass(obj):
self._flatten_dict_obj(obj, data)
return data
if util.is_sequence_subclass(obj):
return self._flatten_sequence_obj(obj, data)
if util.is_noncomplex(obj):
return [self._flatten(v) for v in obj]
if util.is_iterator(obj):
# force list in python 3
data[tags.ITERATOR] = list(map(self._flatten, islice(obj, self._max_iter)))
return data
if reduce_val and not isinstance(reduce_val, (str, unicode)):
# at this point, reduce_val should be some kind of iterable
# pad out to len 5
rv_as_list = list(reduce_val)
insufficiency = 5 - len(rv_as_list)
if insufficiency:
rv_as_list+=[None]*insufficiency
if rv_as_list[0].__name__ == '__newobj__':
rv_as_list[0] = tags.NEWOBJ
data[tags.REDUCE] = list(map(self._flatten, rv_as_list))
# lift out iterators, so we don't have to iterator and uniterator their content
# on unpickle
if data[tags.REDUCE][3]:
data[tags.REDUCE][3] = data[tags.REDUCE][3][tags.ITERATOR]
if data[tags.REDUCE][4]:
data[tags.REDUCE][4] = data[tags.REDUCE][4][tags.ITERATOR]
return data
if has_dict:
# Support objects that subclasses list and set
if util.is_sequence_subclass(obj):
return self._flatten_sequence_obj(obj, data)
# hack for zope persistent objects; this unghostifies the object
getattr(obj, '_', None)
return self._flatten_dict_obj(obj.__dict__, data)
if has_slots:
return self._flatten_newstyle_with_slots(obj, data)
self._pickle_warning(obj)
return None