cti-python-stix2/stix2/environment.py

69 lines
2.9 KiB
Python

import copy
class ObjectFactory(object):
"""Object Factory
Used to easily create STIX objects with default values for certain
properties.
Args:
created_by_ref: Default created_by_ref value to apply to all
objects created by this factory.
created: Default created value to apply to all
objects created by this factory.
external_references: Default `external_references` value to apply
to all objects created by this factory.
object_marking_refs: Default `object_marking_refs` value to apply
to all objects created by this factory.
list_append: When a default is set for a list property like
`external_references` or `object_marking_refs` and a value for
that property is passed into `create()`, if this is set to True,
that value will be added to the list alongside the default. If
this is set to False, the passed in value will replace the
default. Defaults to True.
"""
def __init__(self, created_by_ref=None, created=None,
external_references=None, object_marking_refs=None,
list_append=True):
self._defaults = {}
if created_by_ref:
self._defaults['created_by_ref'] = created_by_ref
if created:
self._defaults['created'] = created
# If the user provides a default "created" time, we also want to use
# that as the modified time.
self._defaults['modified'] = created
if external_references:
self._defaults['external_references'] = external_references
if object_marking_refs:
self._defaults['object_marking_refs'] = object_marking_refs
self._list_append = list_append
self._list_properties = ['external_references', 'object_marking_refs']
def create(self, cls, **kwargs):
# Use self.defaults as the base, but update with any explicit args
# provided by the user.
properties = copy.deepcopy(self._defaults)
if kwargs:
if self._list_append:
# Append provided items to list properties instead of replacing them
for list_prop in set(self._list_properties).intersection(kwargs.keys(), properties.keys()):
kwarg_prop = kwargs.pop(list_prop)
if kwarg_prop is None:
del properties[list_prop]
continue
if not isinstance(properties[list_prop], list):
properties[list_prop] = [properties[list_prop]]
if isinstance(kwarg_prop, list):
properties[list_prop].extend(kwarg_prop)
else:
properties[list_prop].append(kwarg_prop)
properties.update(**kwargs)
return cls(**properties)