move classes and methods from base.py to serialize.py

stix2/base.py

@@ -1,7 +1,6 @@
 """Base classes for type definitions in the STIX2 library."""
 
 import copy
-import datetime as dt
 import re
 import uuid
 
@@ -18,9 +17,10 @@ from .exceptions import (
 )
 from .markings import _MarkingsMixin
 from .markings.utils import validate
-from .utils import (
+from .serialize import (
-    NOW, PREFIX_21_REGEX, find_property_index, format_datetime, get_timestamp,
+    STIXJSONEncoder, STIXJSONIncludeOptionalDefaultsEncoder, serialize,
 )
+from .utils import NOW, PREFIX_21_REGEX, get_timestamp
 from .versioning import new_version as _new_version
 from .versioning import revoke as _revoke
 
@@ -29,88 +29,14 @@ try:
 except ImportError:
     from collections import Mapping
 
-
+# TODO: Remove STIXJSONEncoder, STIXJSONIncludeOptionalDefaultsEncoder, serialize from __all__ on next major release.
-__all__ = ['STIXJSONEncoder', '_STIXBase', 'serialize']
+# Kept for backwards compatibility.
+__all__ = ['STIXJSONEncoder', 'STIXJSONIncludeOptionalDefaultsEncoder', '_STIXBase', 'serialize']
 
 DEFAULT_ERROR = "{type} must have {property}='{expected}'."
 SCO_DET_ID_NAMESPACE = uuid.UUID("00abedb4-aa42-466c-9c01-fed23315a9b7")
 
 
-class STIXJSONEncoder(json.JSONEncoder):
-    """Custom JSONEncoder subclass for serializing Python ``stix2`` objects.
-
-    If an optional property with a default value specified in the STIX 2 spec
-    is set to that default value, it will be left out of the serialized output.
-
-    An example of this type of property include the ``revoked`` common property.
-    """
-
-    def default(self, obj):
-        if isinstance(obj, (dt.date, dt.datetime)):
-            return format_datetime(obj)
-        elif isinstance(obj, _STIXBase):
-            tmp_obj = dict(copy.deepcopy(obj))
-            for prop_name in obj._defaulted_optional_properties:
-                del tmp_obj[prop_name]
-            return tmp_obj
-        else:
-            return super(STIXJSONEncoder, self).default(obj)
-
-
-class STIXJSONIncludeOptionalDefaultsEncoder(json.JSONEncoder):
-    """Custom JSONEncoder subclass for serializing Python ``stix2`` objects.
-
-    Differs from ``STIXJSONEncoder`` in that if an optional property with a default
-    value specified in the STIX 2 spec is set to that default value, it will be
-    included in the serialized output.
-    """
-
-    def default(self, obj):
-        if isinstance(obj, (dt.date, dt.datetime)):
-            return format_datetime(obj)
-        elif isinstance(obj, _STIXBase):
-            return dict(obj)
-        else:
-            return super(STIXJSONIncludeOptionalDefaultsEncoder, self).default(obj)
-
-
-def serialize(obj, pretty=False, include_optional_defaults=False, **kwargs):
-    """
-    Serialize a STIX object.
-
-    Args:
-        obj: The STIX object to be serialized.
-        pretty (bool): If True, output properties following the STIX specs
-            formatting. This includes indentation. Refer to notes for more
-            details. (Default: ``False``)
-        include_optional_defaults (bool): Determines whether to include
-            optional properties set to the default value defined in the spec.
-        **kwargs: The arguments for a json.dumps() call.
-
-    Returns:
-        str: The serialized JSON object.
-
-    Note:
-        The argument ``pretty=True`` will output the STIX object following
-        spec order. Using this argument greatly impacts object serialization
-        performance. If your use case is centered across machine-to-machine
-        operation it is recommended to set ``pretty=False``.
-
-        When ``pretty=True`` the following key-value pairs will be added or
-        overridden: indent=4, separators=(",", ": "), item_sort_key=sort_by.
-    """
-    if pretty:
-        def sort_by(element):
-            return find_property_index(obj, *element)
-
-        kwargs.update({'indent': 4, 'separators': (',', ': '), 'item_sort_key': sort_by})
-
-    if include_optional_defaults:
-        return json.dumps(obj, cls=STIXJSONIncludeOptionalDefaultsEncoder, **kwargs)
-    else:
-        return json.dumps(obj, cls=STIXJSONEncoder, **kwargs)
-
-
 def get_required_properties(properties):
     return (k for k, v in properties.items() if v.required)
 

stix2/serialize.py

@@ -0,0 +1,84 @@
+"""STIX2 core serialization methods."""
+
+import copy
+import datetime as dt
+
+import simplejson as json
+
+from .base import _STIXBase
+from .utils import find_property_index, format_datetime
+
+
+class STIXJSONEncoder(json.JSONEncoder):
+    """Custom JSONEncoder subclass for serializing Python ``stix2`` objects.
+
+    If an optional property with a default value specified in the STIX 2 spec
+    is set to that default value, it will be left out of the serialized output.
+
+    An example of this type of property include the ``revoked`` common property.
+    """
+
+    def default(self, obj):
+        if isinstance(obj, (dt.date, dt.datetime)):
+            return format_datetime(obj)
+        elif isinstance(obj, _STIXBase):
+            tmp_obj = dict(copy.deepcopy(obj))
+            for prop_name in obj._defaulted_optional_properties:
+                del tmp_obj[prop_name]
+            return tmp_obj
+        else:
+            return super(STIXJSONEncoder, self).default(obj)
+
+
+class STIXJSONIncludeOptionalDefaultsEncoder(json.JSONEncoder):
+    """Custom JSONEncoder subclass for serializing Python ``stix2`` objects.
+
+    Differs from ``STIXJSONEncoder`` in that if an optional property with a default
+    value specified in the STIX 2 spec is set to that default value, it will be
+    included in the serialized output.
+    """
+
+    def default(self, obj):
+        if isinstance(obj, (dt.date, dt.datetime)):
+            return format_datetime(obj)
+        elif isinstance(obj, _STIXBase):
+            return dict(obj)
+        else:
+            return super(STIXJSONIncludeOptionalDefaultsEncoder, self).default(obj)
+
+
+def serialize(obj, pretty=False, include_optional_defaults=False, **kwargs):
+    """
+    Serialize a STIX object.
+
+    Args:
+        obj: The STIX object to be serialized.
+        pretty (bool): If True, output properties following the STIX specs
+            formatting. This includes indentation. Refer to notes for more
+            details. (Default: ``False``)
+        include_optional_defaults (bool): Determines whether to include
+            optional properties set to the default value defined in the spec.
+        **kwargs: The arguments for a json.dumps() call.
+
+    Returns:
+        str: The serialized JSON object.
+
+    Note:
+        The argument ``pretty=True`` will output the STIX object following
+        spec order. Using this argument greatly impacts object serialization
+        performance. If your use case is centered across machine-to-machine
+        operation it is recommended to set ``pretty=False``.
+
+        When ``pretty=True`` the following key-value pairs will be added or
+        overridden: indent=4, separators=(",", ": "), item_sort_key=sort_by.
+    """
+    if pretty:
+        def sort_by(element):
+            return find_property_index(obj, *element)
+
+        kwargs.update({'indent': 4, 'separators': (',', ': '), 'item_sort_key': sort_by})
+
+    if include_optional_defaults:
+        return json.dumps(obj, cls=STIXJSONIncludeOptionalDefaultsEncoder, **kwargs)
+    else:
+        return json.dumps(obj, cls=STIXJSONEncoder, **kwargs)