jsons.serializers.default_object._add_dumped_elem() - Code Metrics - Inspection of "Merge pull request #80 from ramonhagenaars/Release..." - ramonhagenaars/jsons - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( 5ea888...aa565f )

by Ramon

created 2019-12-22 14:02 UTC

_add_dumped_elem() A

↳ Parent: jsons.serializers.default_object

Complexity

Conditions

Size

Total Lines	10
Code Lines	10

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
eloc	10
dl	0
loc	10
rs	9.9
c	0
b	0
f	0
cc	4
nop	5

from datetime import datetime, timezone
from inspect import isfunction
from typing import Optional, Callable, Union, MutableSequence, Tuple, Dict

from typish import get_type

from jsons._cache import cached
from jsons._common_impl import get_class_name, META_ATTR, StateHolder
from jsons._compatibility_impl import get_type_hints
from jsons._datetime_impl import to_str
from jsons._dump_impl import dump
from jsons.classes import JsonSerializable
from jsons.classes.verbosity import Verbosity
from jsons.exceptions import SerializationError, RecursionDetectedError


def default_object_serializer(
        obj: object,
        cls: Optional[type] = None,
        *,
        key_transformer: Optional[Callable[[str], str]] = None,
        strip_nulls: bool = False,
        strip_privates: bool = False,
        strip_properties: bool = False,
        strip_class_variables: bool = False,
        strip_attr: Union[str, MutableSequence[str], Tuple[str]] = None,
        verbose: Union[Verbosity, bool] = False,
        strict: bool = False,
        fork_inst: Optional[type] = StateHolder,
        **kwargs) -> Optional[dict]:
    """
    Serialize the given ``obj`` to a dict. All values within ``obj`` are also
    serialized. If ``key_transformer`` is given, it will be used to transform
    the casing (e.g. snake_case) to a different format (e.g. camelCase).
    :param obj: the object that is to be serialized.
    :param cls: the type of the object that is to be dumped.
    :param key_transformer: a function that will be applied to all keys in the
    resulting dict.
    :param strip_nulls: if ``True`` the resulting dict will not contain null
    values.
    :param strip_privates: if ``True`` the resulting dict will not contain
    private attributes (i.e. attributes that start with an underscore).
    :param strip_properties: if ``True`` the resulting dict will not contain
    values from @properties.
    :param strip_class_variables: if ``True`` the resulting dict will not
    contain values from class variables.
    :param strip_attr: can be a name or a collection of names of attributes
    that are not to be included in the dump.
    dict will not contain attributes with
    :param verbose: if ``True`` the resulting dict will contain meta
    information (e.g. on how to deserialize).
    :param strict: a bool to determine if the serializer should be strict
    (i.e. only dumping stuff that is known to ``cls``).
    :param fork_inst: if given, it uses this fork of ``JsonSerializable``.
    :param kwargs: any keyword arguments that are to be passed to the
    serializer functions.
    :return: a Python dict holding the values of ``obj``.
    """
    if obj is None:
        return obj
    strip_attr = _normalize_strip_attr(strip_attr)
    if cls and strict:
        attributes = _get_attributes_from_class(
            cls, strip_privates, strip_properties, strip_class_variables,
            strip_attr, strict)
    else:
        attributes = _get_attributes_from_object(
            obj, strip_privates, strip_properties, strip_class_variables,
            strip_attr, strict)
        cls = obj.__class__
    verbose = Verbosity.from_value(verbose)
    kwargs_ = {
        **kwargs,
        'fork_inst': fork_inst,
        'verbose': verbose,
        'strict': strict,
        # Set a flag in kwargs to temporarily store -cls:
        '_store_cls': Verbosity.WITH_CLASS_INFO in verbose
    }

    result = _do_serialize(obj=obj,
                           cls=cls,
                           attributes=attributes,
                           kwargs=kwargs_,
                           key_transformer=key_transformer,
                           strip_nulls=strip_nulls,
                           strip_privates=strip_privates,
                           strip_properties=strip_properties,
                           strip_class_variables=strip_class_variables,
                           strip_attr=strip_attr,
                           strict=strict,
                           fork_inst=fork_inst)

    cls_name = get_class_name(cls, fully_qualified=True)
    if not kwargs.get('_store_cls'):
        result = _get_dict_with_meta(result, cls_name, verbose, fork_inst)
    return result


def _do_serialize(
        obj: object,
        cls: type,
        attributes: Dict[str, Optional[type]],
        kwargs: dict,
        key_transformer: Optional[Callable[[str], str]] = None,
        strip_nulls: bool = False,
        strip_privates: bool = False,
        strip_properties: bool = False,
        strip_class_variables: bool = False,
        strip_attr: Union[str, MutableSequence[str], Tuple[str]] = None,
        strict: bool = False,
        fork_inst: Optional[type] = StateHolder) -> Dict[str, object]:
    result = dict()
    for attr_name, cls_ in attributes.items():
        attr = obj.__getattribute__(attr_name)
        dumped_elem = None
        try:
            dumped_elem = dump(attr,
                               cls=cls_,
                               key_transformer=key_transformer,
                               strip_nulls=strip_nulls,
                               strip_privates=strip_privates,
                               strip_properties=strip_properties,
                               strip_class_variables=strip_class_variables,
                               strip_attr=strip_attr,
                               **kwargs)
            _store_cls_info(dumped_elem, attr, kwargs)
        except RecursionDetectedError:
            fork_inst._warn('Recursive structure detected in attribute "{}" '
                            'of object of type "{}", ignoring the attribute.'
                            .format(attr_name, get_class_name(cls)))
        except SerializationError as err:
            if strict:
                raise
            else:
                fork_inst._warn('Failed to dump attribute "{}" of object of '
                                'type "{}". Reason: {}. Ignoring the '
                                'attribute.'
                                .format(attr, get_class_name(cls), err.message))
                break
        _add_dumped_elem(result, attr_name, dumped_elem,
                         strip_nulls, key_transformer)
    return result


def _add_dumped_elem(
        result: dict,
        attr_name: str,
        dumped_elem: object,
        strip_nulls: bool,
        key_transformer: Optional[Callable[[str], str]]):
    if not (strip_nulls and dumped_elem is None):
        if key_transformer:
            attr_name = key_transformer(attr_name)
        result[attr_name] = dumped_elem


def _normalize_strip_attr(strip_attr) -> tuple:
    # Make sure that strip_attr is always a tuple.
    strip_attr = strip_attr or tuple()
    if (not isinstance(strip_attr, MutableSequence)
            and not isinstance(strip_attr, tuple)):
        strip_attr = (strip_attr,)
    return strip_attr


@cached
def _get_attributes_from_class(
        cls: type,
        strip_privates: bool,
        strip_properties: bool,
        strip_class_variables: bool,
        strip_attr: tuple,
        strict: bool) -> Dict[str, Optional[type]]:
    # Get the attributes that are known in the class.
    attributes_and_types = _get_attributes_and_types(cls, strict)
    return _filter_attributes(cls, attributes_and_types, strip_privates,
                              strip_properties, strip_class_variables,
                              strip_attr)


def _get_attributes_from_object(
        obj: object,
        strip_privates: bool,
        strip_properties: bool,
        strip_class_variables: bool,
        strip_attr: tuple,
        strict: bool) -> Dict[str, Optional[type]]:
    # Get the attributes that are known in the object.
    cls = obj.__class__
    attributes_and_types = _get_attributes_and_types(cls, strict)
    attributes = {attr: attributes_and_types.get(attr, None)
                  for attr in dir(obj)}
    return _filter_attributes(cls, attributes, strip_privates,
                              strip_properties, strip_class_variables,
                              strip_attr)


@cached
def _get_attributes_and_types(cls: type,
                              strict: bool) -> Dict[str, Optional[type]]:
    if '__slots__' in cls.__dict__:
        attributes = {attr: None for attr in cls.__slots__}
    elif hasattr(cls, '__annotations__'):
        attributes = cls.__annotations__
    elif strict:
        hints = get_type_hints(cls.__init__)
        attributes = {k: hints[k] for k in hints if k != 'self'}
    else:
        attributes = {}

    # Add properties and class variables.
    props, class_vars = _get_class_props(cls)
    for elem in props + class_vars:
        attributes[elem] = None

    return attributes


def _filter_attributes(
        cls: type,
        attributes: Dict[str, Optional[type]],
        strip_privates: bool,
        strip_properties: bool,
        strip_class_variables: bool,
        strip_attr: tuple) -> Dict[str, Optional[type]]:
    # Filter the given attributes with the given preferences.
    strip_attr = strip_attr + _ABC_ATTRS
    excluded_elems = dir(JsonSerializable)
    props, other_cls_vars = _get_class_props(cls)

    return {attr: type_ for attr, type_ in attributes.items()
            if not attr.startswith('__')
            and not (strip_privates and attr.startswith('_'))
            and not (strip_properties and attr in props)
            and not (strip_class_variables and attr in other_cls_vars)
            and attr not in strip_attr
            and attr != 'json'
            and not isfunction(getattr(cls, attr, None))
            and attr not in excluded_elems}


def _get_class_props(cls: type) -> Tuple[list, list]:
    props = []
    other_cls_vars = []
    for n, v in _get_complete_class_dict(cls).items():
        list_to_append = props if isinstance(v, property) else other_cls_vars
        list_to_append.append(n)
    return props, other_cls_vars


def _get_complete_class_dict(cls: type) -> dict:
    cls_dict = {}
    # Loop reversed so values of sub-classes override those of super-classes.
    for cls_or_elder in reversed(cls.mro()):
        cls_dict.update(cls_or_elder.__dict__)
    return cls_dict


def _get_dict_with_meta(
        obj: dict,
        cls_name: str,
        verbose: Verbosity,
        fork_inst: type) -> dict:
    # This function will add a -meta section to the given obj (provided that
    # the given obj has -cls attributes for all children).
    if verbose is Verbosity.WITH_NOTHING:
        return obj

    obj[META_ATTR] = {}
    if Verbosity.WITH_CLASS_INFO in verbose:
        collection_of_types = {}
        _fill_collection_of_types(obj, cls_name, '/', collection_of_types)
        collection_of_types['/'] = cls_name
        obj[META_ATTR]['classes'] = collection_of_types
    if Verbosity.WITH_DUMP_TIME in verbose:
        dump_time = to_str(datetime.now(tz=timezone.utc), True, fork_inst)
        obj[META_ATTR]['dump_time'] = dump_time
    return obj


def _fill_collection_of_types(
        obj_: dict,
        cls_name_: Optional[str],
        prefix: str,
        collection_of_types_: dict) -> str:
    # This function loops through obj_ to fill collection_of_types_ with the
    # class names. All of the -cls attributes are removed in the process.
    cls_name_ = _get_class_name_and_strip_cls(cls_name_, obj_)
    for attr in obj_:
        if attr != META_ATTR and isinstance(obj_[attr], dict):
            attr_class = _fill_collection_of_types(obj_[attr],
                                                   None,
                                                   prefix + attr + '/',
                                                   collection_of_types_)
            collection_of_types_[prefix + attr] = attr_class
    return cls_name_


def _get_class_name_and_strip_cls(cls_name: Optional[str], obj: dict) -> str:
    result = cls_name
    if not cls_name and '-cls' in obj:
        result = obj['-cls']
    if '-cls' in obj:
        del obj['-cls']
    return result


def _store_cls_info(result: object, original_obj: dict, kwargs):
    if kwargs.get('_store_cls', None) and isinstance(result, dict):
        cls = get_type(original_obj)
        if cls.__module__ == 'typing':
            cls_name = repr(cls)
        else:
            cls_name = get_class_name(cls, fully_qualified=True)
        result['-cls'] = cls_name


_ABC_ATTRS = ('_abc_registry', '_abc_cache', '_abc_negative_cache',
              '_abc_negative_cache_version', '_abc_impl')


1			from datetime import datetime, timezone
2			from inspect import isfunction
3			from typing import Optional, Callable, Union, MutableSequence, Tuple, Dict
4
5			from typish import get_type
6
7			from jsons._cache import cached
8			from jsons._common_impl import get_class_name, META_ATTR, StateHolder
9			from jsons._compatibility_impl import get_type_hints
10			from jsons._datetime_impl import to_str
11			from jsons._dump_impl import dump
12			from jsons.classes import JsonSerializable
13			from jsons.classes.verbosity import Verbosity
14			from jsons.exceptions import SerializationError, RecursionDetectedError
15
16
17			def default_object_serializer(
18			obj: object,
19			cls: Optional[type] = None,
20			*,
21			key_transformer: Optional[Callable[[str], str]] = None,
22			strip_nulls: bool = False,
23			strip_privates: bool = False,
24			strip_properties: bool = False,
25			strip_class_variables: bool = False,
26			strip_attr: Union[str, MutableSequence[str], Tuple[str]] = None,
27			verbose: Union[Verbosity, bool] = False,
28			strict: bool = False,
29			fork_inst: Optional[type] = StateHolder,
30			**kwargs) -> Optional[dict]:
31			"""
32			Serialize the given ``obj`` to a dict. All values within ``obj`` are also
33			serialized. If ``key_transformer`` is given, it will be used to transform
34			the casing (e.g. snake_case) to a different format (e.g. camelCase).
35			:param obj: the object that is to be serialized.
36			:param cls: the type of the object that is to be dumped.
37			:param key_transformer: a function that will be applied to all keys in the
38			resulting dict.
39			:param strip_nulls: if ``True`` the resulting dict will not contain null
40			values.
41			:param strip_privates: if ``True`` the resulting dict will not contain
42			private attributes (i.e. attributes that start with an underscore).
43			:param strip_properties: if ``True`` the resulting dict will not contain
44			values from @properties.
45			:param strip_class_variables: if ``True`` the resulting dict will not
46			contain values from class variables.
47			:param strip_attr: can be a name or a collection of names of attributes
48			that are not to be included in the dump.
49			dict will not contain attributes with
50			:param verbose: if ``True`` the resulting dict will contain meta
51			information (e.g. on how to deserialize).
52			:param strict: a bool to determine if the serializer should be strict
53			(i.e. only dumping stuff that is known to ``cls``).
54			:param fork_inst: if given, it uses this fork of ``JsonSerializable``.
55			:param kwargs: any keyword arguments that are to be passed to the
56			serializer functions.
57			:return: a Python dict holding the values of ``obj``.
58			"""
59			if obj is None:
60			return obj
61			strip_attr = _normalize_strip_attr(strip_attr)
62			if cls and strict:
63			attributes = _get_attributes_from_class(
64			cls, strip_privates, strip_properties, strip_class_variables,
65			strip_attr, strict)
66			else:
67			attributes = _get_attributes_from_object(
68			obj, strip_privates, strip_properties, strip_class_variables,
69			strip_attr, strict)
70			cls = obj.__class__
71			verbose = Verbosity.from_value(verbose)
72			kwargs_ = {
73			**kwargs,
74			'fork_inst': fork_inst,
75			'verbose': verbose,
76			'strict': strict,
77			# Set a flag in kwargs to temporarily store -cls:
78			'_store_cls': Verbosity.WITH_CLASS_INFO in verbose
79			}
80
81			result = _do_serialize(obj=obj,
82			cls=cls,
83			attributes=attributes,
84			kwargs=kwargs_,
85			key_transformer=key_transformer,
86			strip_nulls=strip_nulls,
87			strip_privates=strip_privates,
88			strip_properties=strip_properties,
89			strip_class_variables=strip_class_variables,
90			strip_attr=strip_attr,
91			strict=strict,
92			fork_inst=fork_inst)
93
94			cls_name = get_class_name(cls, fully_qualified=True)
95			if not kwargs.get('_store_cls'):
96			result = _get_dict_with_meta(result, cls_name, verbose, fork_inst)
97			return result
98
99
100			def _do_serialize(
101			obj: object,
102			cls: type,
103			attributes: Dict[str, Optional[type]],
104			kwargs: dict,
105			key_transformer: Optional[Callable[[str], str]] = None,
106			strip_nulls: bool = False,
107			strip_privates: bool = False,
108			strip_properties: bool = False,
109			strip_class_variables: bool = False,
110			strip_attr: Union[str, MutableSequence[str], Tuple[str]] = None,
111			strict: bool = False,
112			fork_inst: Optional[type] = StateHolder) -> Dict[str, object]:
113			result = dict()
114			for attr_name, cls_ in attributes.items():
115			attr = obj.__getattribute__(attr_name)
116			dumped_elem = None
117			try:
118			dumped_elem = dump(attr,
119			cls=cls_,
120			key_transformer=key_transformer,
121			strip_nulls=strip_nulls,
122			strip_privates=strip_privates,
123			strip_properties=strip_properties,
124			strip_class_variables=strip_class_variables,
125			strip_attr=strip_attr,
126			**kwargs)
127			_store_cls_info(dumped_elem, attr, kwargs)
128			except RecursionDetectedError:
129			fork_inst._warn('Recursive structure detected in attribute "{}" '
130			'of object of type "{}", ignoring the attribute.'
131			.format(attr_name, get_class_name(cls)))
132			except SerializationError as err:
133			if strict:
134			raise
135			else:
136			fork_inst._warn('Failed to dump attribute "{}" of object of '
137			'type "{}". Reason: {}. Ignoring the '
138			'attribute.'
139			.format(attr, get_class_name(cls), err.message))
140			break
141			_add_dumped_elem(result, attr_name, dumped_elem,
142			strip_nulls, key_transformer)
143			return result
144
145
146			def _add_dumped_elem(
147			result: dict,
148			attr_name: str,
149			dumped_elem: object,
150			strip_nulls: bool,
151			key_transformer: Optional[Callable[[str], str]]):
152			if not (strip_nulls and dumped_elem is None):
153			if key_transformer:
154			attr_name = key_transformer(attr_name)
155			result[attr_name] = dumped_elem
156
157
158			def _normalize_strip_attr(strip_attr) -> tuple:
159			# Make sure that strip_attr is always a tuple.
160			strip_attr = strip_attr or tuple()
161			if (not isinstance(strip_attr, MutableSequence)
162			and not isinstance(strip_attr, tuple)):
163			strip_attr = (strip_attr,)
164			return strip_attr
165
166
167			@cached
168			def _get_attributes_from_class(
169			cls: type,
170			strip_privates: bool,
171			strip_properties: bool,
172			strip_class_variables: bool,
173			strip_attr: tuple,
174			strict: bool) -> Dict[str, Optional[type]]:
175			# Get the attributes that are known in the class.
176			attributes_and_types = _get_attributes_and_types(cls, strict)
177			return _filter_attributes(cls, attributes_and_types, strip_privates,
178			strip_properties, strip_class_variables,
179			strip_attr)
180
181
182			def _get_attributes_from_object(
183			obj: object,
184			strip_privates: bool,
185			strip_properties: bool,
186			strip_class_variables: bool,
187			strip_attr: tuple,
188			strict: bool) -> Dict[str, Optional[type]]:
189			# Get the attributes that are known in the object.
190			cls = obj.__class__
191			attributes_and_types = _get_attributes_and_types(cls, strict)
192			attributes = {attr: attributes_and_types.get(attr, None)
193			for attr in dir(obj)}
194			return _filter_attributes(cls, attributes, strip_privates,
195			strip_properties, strip_class_variables,
196			strip_attr)
197
198
199			@cached
200			def _get_attributes_and_types(cls: type,
201			strict: bool) -> Dict[str, Optional[type]]:
202			if '__slots__' in cls.__dict__:
203			attributes = {attr: None for attr in cls.__slots__}
204			elif hasattr(cls, '__annotations__'):
205			attributes = cls.__annotations__
206			elif strict:
207			hints = get_type_hints(cls.__init__)
208			attributes = {k: hints[k] for k in hints if k != 'self'}
209			else:
210			attributes = {}
211
212			# Add properties and class variables.
213			props, class_vars = _get_class_props(cls)
214			for elem in props + class_vars:
215			attributes[elem] = None
216
217			return attributes
218
219
220			def _filter_attributes(
221			cls: type,
222			attributes: Dict[str, Optional[type]],
223			strip_privates: bool,
224			strip_properties: bool,
225			strip_class_variables: bool,
226			strip_attr: tuple) -> Dict[str, Optional[type]]:
227			# Filter the given attributes with the given preferences.
228			strip_attr = strip_attr + _ABC_ATTRS
229			excluded_elems = dir(JsonSerializable)
230			props, other_cls_vars = _get_class_props(cls)
231
232			return {attr: type_ for attr, type_ in attributes.items()
233			if not attr.startswith('__')
234			and not (strip_privates and attr.startswith('_'))
235			and not (strip_properties and attr in props)
236			and not (strip_class_variables and attr in other_cls_vars)
237			and attr not in strip_attr
238			and attr != 'json'
239			and not isfunction(getattr(cls, attr, None))
240			and attr not in excluded_elems}
241
242
243			def _get_class_props(cls: type) -> Tuple[list, list]:
244			props = []
245			other_cls_vars = []
246			for n, v in _get_complete_class_dict(cls).items():
247			list_to_append = props if isinstance(v, property) else other_cls_vars
248			list_to_append.append(n)
249			return props, other_cls_vars
250
251
252			def _get_complete_class_dict(cls: type) -> dict:
253			cls_dict = {}
254			# Loop reversed so values of sub-classes override those of super-classes.
255			for cls_or_elder in reversed(cls.mro()):
256			cls_dict.update(cls_or_elder.__dict__)
257			return cls_dict
258
259
260			def _get_dict_with_meta(
261			obj: dict,
262			cls_name: str,
263			verbose: Verbosity,
264			fork_inst: type) -> dict:
265			# This function will add a -meta section to the given obj (provided that
266			# the given obj has -cls attributes for all children).
267			if verbose is Verbosity.WITH_NOTHING:
268			return obj
269
270			obj[META_ATTR] = {}
271			if Verbosity.WITH_CLASS_INFO in verbose:
272			collection_of_types = {}
273			_fill_collection_of_types(obj, cls_name, '/', collection_of_types)
274			collection_of_types['/'] = cls_name
275			obj[META_ATTR]['classes'] = collection_of_types
276			if Verbosity.WITH_DUMP_TIME in verbose:
277			dump_time = to_str(datetime.now(tz=timezone.utc), True, fork_inst)
278			obj[META_ATTR]['dump_time'] = dump_time
279			return obj
280
281
282			def _fill_collection_of_types(
283			obj_: dict,
284			cls_name_: Optional[str],
285			prefix: str,
286			collection_of_types_: dict) -> str:
287			# This function loops through obj_ to fill collection_of_types_ with the
288			# class names. All of the -cls attributes are removed in the process.
289			cls_name_ = _get_class_name_and_strip_cls(cls_name_, obj_)
290			for attr in obj_:
291			if attr != META_ATTR and isinstance(obj_[attr], dict):
292			attr_class = _fill_collection_of_types(obj_[attr],
293			None,
294			prefix + attr + '/',
295			collection_of_types_)
296			collection_of_types_[prefix + attr] = attr_class
297			return cls_name_
298
299
300			def _get_class_name_and_strip_cls(cls_name: Optional[str], obj: dict) -> str:
301			result = cls_name
302			if not cls_name and '-cls' in obj:
303			result = obj['-cls']
304			if '-cls' in obj:
305			del obj['-cls']
306			return result
307
308
309			def _store_cls_info(result: object, original_obj: dict, kwargs):
310			if kwargs.get('_store_cls', None) and isinstance(result, dict):
311			cls = get_type(original_obj)
312			if cls.__module__ == 'typing':
313			cls_name = repr(cls)
314			else:
315			cls_name = get_class_name(cls, fully_qualified=True)
316			result['-cls'] = cls_name
317
318
319			_ABC_ATTRS = ('_abc_registry', '_abc_cache', '_abc_negative_cache',
320			'_abc_negative_cache_version', '_abc_impl')
321

ramonhagenaars / jsons

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_add_dumped_elem() A

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