| """ |
| This module provides serializable, validatable, type-enforcing domain objects and data |
| transfer objects. It has many of the same motivations as the python |
| `Marshmallow <http://marshmallow.readthedocs.org/en/latest/why.html>`_ package. It is most |
| similar to `Schematics <http://schematics.readthedocs.io/>`_. |
| |
| ======== |
| Tutorial |
| ======== |
| |
| Chapter 1: Entity and Field Basics |
| ---------------------------------- |
| |
| >>> class Color(Enum): |
| ... blue = 0 |
| ... black = 1 |
| ... red = 2 |
| >>> class Car(Entity): |
| ... weight = NumberField(required=False) |
| ... wheels = IntField(default=4, validation=lambda x: 3 <= x <= 4) |
| ... color = EnumField(Color) |
| |
| >>> # create a new car object |
| >>> car = Car(color=Color.blue, weight=4242.46) |
| >>> car |
| Car(weight=4242.46, color=0) |
| |
| >>> # it has 4 wheels, all by default |
| >>> car.wheels |
| 4 |
| |
| >>> # but a car can't have 5 wheels! |
| >>> # the `validation=` field is a simple callable that returns a |
| >>> # boolean based on validity |
| >>> car.wheels = 5 |
| Traceback (most recent call last): |
| ValidationError: Invalid value 5 for wheels |
| |
| >>> # we can call .dump() on car, and just get back a standard |
| >>> # python dict actually, it's an ordereddict to match attribute |
| >>> # declaration order |
| >>> type(car.dump()) |
| <class '...OrderedDict'> |
| >>> car.dump() |
| OrderedDict([('weight', 4242.46), ('wheels', 4), ('color', 0)]) |
| |
| >>> # and json too (note the order!) |
| >>> car.json() |
| '{"weight": 4242.46, "wheels": 4, "color": 0}' |
| |
| >>> # green cars aren't allowed |
| >>> car.color = "green" |
| Traceback (most recent call last): |
| ValidationError: 'green' is not a valid Color |
| |
| >>> # but black cars are! |
| >>> car.color = "black" |
| >>> car.color |
| <Color.black: 1> |
| |
| >>> # car.color really is an enum, promise |
| >>> type(car.color) |
| <enum 'Color'> |
| |
| >>> # enum assignment can be with any of (and preferentially) |
| >>> # (1) an enum literal, |
| >>> # (2) a valid enum value, or |
| >>> # (3) a valid enum name |
| >>> car.color = Color.blue; car.color.value |
| 0 |
| >>> car.color = 1; car.color.name |
| 'black' |
| |
| >>> # let's do a round-trip marshalling of this thing |
| >>> same_car = Car.from_json(car.json()) # or equally Car.from_json(json.dumps(car.dump())) |
| >>> same_car == car |
| True |
| |
| >>> # actually, they're two different instances |
| >>> same_car is not car |
| True |
| |
| >>> # this works too |
| >>> cloned_car = Car(**car.dump()) |
| >>> cloned_car == car |
| True |
| |
| >>> # while we're at it, these are all equivalent too |
| >>> car == Car.from_objects(car) |
| True |
| >>> car == Car.from_objects({"weight": 4242.46, "wheels": 4, "color": 1}) |
| True |
| >>> car == Car.from_json('{"weight": 4242.46, "color": 1}') |
| True |
| |
| >>> # .from_objects() even lets you stack and combine objects |
| >>> class DumbClass: |
| ... color = 0 |
| ... wheels = 3 |
| >>> Car.from_objects(DumbClass(), dict(weight=2222, color=1)) |
| Car(weight=2222, wheels=3, color=0) |
| >>> # and also pass kwargs that override properties pulled |
| >>> # off any objects |
| >>> Car.from_objects(DumbClass(), {'weight': 2222, 'color': 1}, color=2, weight=33) |
| Car(weight=33, wheels=3, color=2) |
| |
| |
| Chapter 2: Entity and Field Composition |
| --------------------------------------- |
| |
| >>> # now let's get fancy |
| >>> # a ComposableField "nests" another valid Entity |
| >>> # a ListField's first argument is a "generic" type, |
| >>> # which can be a valid Entity, any python primitive |
| >>> # type, or a list of Entities/types |
| >>> class Fleet(Entity): |
| ... boss_car = ComposableField(Car) |
| ... cars = ListField(Car) |
| |
| >>> # here's our fleet of company cars |
| >>> company_fleet = Fleet(boss_car=Car(color='red'), cars=[car, same_car, cloned_car]) |
| >>> company_fleet.pretty_json() #doctest: +SKIP |
| { |
| "boss_car": { |
| "wheels": 4 |
| "color": 2, |
| }, |
| "cars": [ |
| { |
| "weight": 4242.46, |
| "wheels": 4 |
| "color": 1, |
| }, |
| { |
| "weight": 4242.46, |
| "wheels": 4 |
| "color": 1, |
| }, |
| { |
| "weight": 4242.46, |
| "wheels": 4 |
| "color": 1, |
| } |
| ] |
| } |
| |
| >>> # the boss' car is red of course (and it's still an Enum) |
| >>> company_fleet.boss_car.color.name |
| 'red' |
| |
| >>> # and there are three cars left for the employees |
| >>> len(company_fleet.cars) |
| 3 |
| |
| |
| Chapter 3: Immutability |
| ----------------------- |
| |
| >>> class ImmutableCar(ImmutableEntity): |
| ... wheels = IntField(default=4, validation=lambda x: 3 <= x <= 4) |
| ... color = EnumField(Color) |
| >>> icar = ImmutableCar.from_objects({'wheels': 3, 'color': 'blue'}) |
| >>> icar |
| ImmutableCar(wheels=3, color=0) |
| |
| >>> icar.wheels = 4 |
| Traceback (most recent call last): |
| AttributeError: Assignment not allowed. ImmutableCar is immutable. |
| |
| >>> class FixedWheelCar(Entity): |
| ... wheels = IntField(default=4, immutable=True) |
| ... color = EnumField(Color) |
| >>> fwcar = FixedWheelCar.from_objects(icar) |
| >>> fwcar.json() |
| '{"wheels": 3, "color": 0}' |
| |
| >>> # repainting the car is easy |
| >>> fwcar.color = Color.red |
| >>> fwcar.color.name |
| 'red' |
| |
| >>> # can't really change the number of wheels though |
| >>> fwcar.wheels = 18 |
| Traceback (most recent call last): |
| AttributeError: The wheels field is immutable. |
| |
| |
| Chapter X: The del and null Weeds |
| --------------------------------- |
| |
| >>> old_date = lambda: isoparse('1982-02-17') |
| >>> class CarBattery(Entity): |
| ... # NOTE: default value can be a callable! |
| ... first_charge = DateField(required=False) # default=None, nullable=False |
| ... latest_charge = DateField(default=old_date, nullable=True) # required=True |
| ... expiration = DateField(default=old_date, required=False, nullable=False) |
| |
| >>> # starting point |
| >>> battery = CarBattery() |
| >>> battery |
| CarBattery() |
| >>> battery.json() |
| '{"latest_charge": "1982-02-17T00:00:00", "expiration": "1982-02-17T00:00:00"}' |
| |
| >>> # first_charge is not assigned a default value. Once one is assigned, it can be deleted, |
| >>> # but it can't be made null. |
| >>> battery.first_charge = isoparse('2016-03-23') |
| >>> battery |
| CarBattery(first_charge=datetime.datetime(2016, 3, 23, 0, 0)) |
| >>> battery.first_charge = None |
| Traceback (most recent call last): |
| ValidationError: Value for first_charge not given or invalid. |
| >>> del battery.first_charge |
| >>> battery |
| CarBattery() |
| |
| >>> # latest_charge can be null, but it can't be deleted. The default value is a callable. |
| >>> del battery.latest_charge |
| Traceback (most recent call last): |
| AttributeError: The latest_charge field is required and cannot be deleted. |
| >>> battery.latest_charge = None |
| >>> battery.json() |
| '{"latest_charge": null, "expiration": "1982-02-17T00:00:00"}' |
| |
| >>> # expiration is assigned by default, can't be made null, but can be deleted. |
| >>> battery.expiration |
| datetime.datetime(1982, 2, 17, 0, 0) |
| >>> battery.expiration = None |
| Traceback (most recent call last): |
| ValidationError: Value for expiration not given or invalid. |
| >>> del battery.expiration |
| >>> battery.json() |
| '{"latest_charge": null}' |
| |
| |
| """ |
|
|
| from collections.abc import Mapping, Sequence |
| from datetime import datetime |
| from enum import Enum |
| from functools import reduce |
| from logging import getLogger |
| from pathlib import Path |
|
|
| from boltons.timeutils import isoparse |
| from frozendict import deepfreeze, frozendict |
| from frozendict import getFreezeConversionMap as _getFreezeConversionMap |
| from frozendict import register as _register |
|
|
| from . import NULL |
| from .compat import odict |
| from ..common.compat import isiterable |
| from .collection import AttrDict |
| from .exceptions import Raise, ValidationError |
| from .ish import find_or_raise |
| from .type_coercion import maybecall |
| from ..common.serialize import json |
| from ..deprecations import deprecated |
|
|
| if Enum not in _getFreezeConversionMap(): |
| |
| |
| _register(Enum, lambda x : x) |
|
|
| del _getFreezeConversionMap |
| del _register |
|
|
| log = getLogger(__name__) |
|
|
| __all__ = [ |
| "Entity", "ImmutableEntity", "Field", |
| "BooleanField", "BoolField", "IntegerField", "IntField", |
| "NumberField", "StringField", "DateField", |
| "EnumField", "ListField", "MapField", "ComposableField", |
| ] |
|
|
| KEY_OVERRIDES_MAP = "__key_overrides__" |
|
|
|
|
| NOTES = """ |
| |
| Current deficiencies to schematics: |
| - no get_mock_object method |
| - no context-dependent serialization or MultilingualStringType |
| - name = StringType(serialized_name='person_name', alternate_names=['human_name']) |
| - name = StringType(serialize_when_none=False) |
| - more flexible validation error messages |
| - field validation can depend on other fields |
| - 'roles' containing denylists for .dump() and .json() |
| __roles__ = { |
| EntityRole.registered_name: Denylist('field1', 'field2'), |
| EntityRole.another_registered_name: Allowlist('field3', 'field4'), |
| } |
| |
| |
| TODO: |
| - alternate field names |
| - add dump_if_null field option |
| - add help/description parameter to Field |
| - consider leveraging slots |
| - collect all validation errors before raising |
| - Allow returning string error message for validation instead of False |
| - profile and optimize |
| - use boltons instead of dateutil |
| - correctly implement copy and deepcopy on fields and Entity, DictSafeMixin |
| http://stackoverflow.com/questions/1500718/what-is-the-right-way-to-override-the-copy-deepcopy-operations-on-an-object-in-p |
| |
| |
| Optional Field Properties: |
| - validation = None |
| - default = None |
| - required = True |
| - in_dump = True |
| - nullable = False |
| |
| Behaviors: |
| - Nullable is a "hard" setting, in that the value is either always or never allowed to be None. |
| - What happens then if required=False and nullable=False? |
| - The object can be init'd without a value (though not with a None value). |
| getattr throws AttributeError |
| - Any assignment must be not None. |
| |
| |
| - Setting a value to None doesn't "unset" a value. (That's what del is for.) And you can't |
| del a value if required=True, nullable=False, default=None. |
| |
| - If a field is not required, del does *not* "unmask" the default value. Instead, del |
| removes the value from the object entirely. To get back the default value, need to recreate |
| the object. Entity.from_objects(old_object) |
| |
| |
| - Disabling in_dump is a "hard" setting, in that with it disabled the field will never get |
| dumped. With it enabled, the field may or may not be dumped depending on its value and other |
| settings. |
| |
| - Required is a "hard" setting, in that if True, a valid value or default must be provided. None |
| is only a valid value or default if nullable is True. |
| |
| - In general, nullable means that None is a valid value. |
| - getattr returns None instead of raising Attribute error |
| - If in_dump, field is given with null value. |
| - If default is not None, assigning None clears a previous assignment. Future getattrs return |
| the default value. |
| - What does nullable mean with default=None and required=True? Does instantiation raise |
| an error if assignment not made on init? Can IntField(nullable=True) be init'd? |
| |
| - If required=False and nullable=False, field will only be in dump if field!=None. |
| Also, getattr raises AttributeError. |
| - If required=False and nullable=True, field will be in dump if field==None. |
| |
| - If in_dump is True, does default value get dumped: |
| - if no assignment, default exists |
| - if nullable, and assigned None |
| - How does optional validation work with nullable and assigning None? |
| - When does gettattr throw AttributeError, and when does it return None? |
| |
| |
| |
| """ |
|
|
|
|
| class Field: |
| """ |
| Fields are doing something very similar to boxing and unboxing |
| of c#/java primitives. __set__ should take a "primitive" or "raw" value and create a "boxed" |
| or "programmatically usable" value of it. While __get__ should return the boxed value, |
| dump in turn should unbox the value into a primitive or raw value. |
| |
| Arguments: |
| types_ (primitive literal or type or sequence of types): |
| default (any, callable, optional): If default is callable, it's guaranteed to return a |
| valid value at the time of Entity creation. |
| required (boolean, optional): |
| validation (callable, optional): |
| dump (boolean, optional): |
| """ |
|
|
| |
| |
| _order_helper = 0 |
|
|
| def __init__(self, default=NULL, required=True, validation=None, |
| in_dump=True, default_in_dump=True, nullable=False, immutable=False, aliases=()): |
| self._required = required |
| self._validation = validation |
| self._in_dump = in_dump |
| self._default_in_dump = default_in_dump |
| self._nullable = nullable |
| self._immutable = immutable |
| self._aliases = aliases |
| if default is NULL: |
| self._default = NULL |
| else: |
| self._default = default if callable(default) else self.box(None, None, default) |
| self.validate(None, self.box(None, None, maybecall(default))) |
|
|
| self._order_helper = Field._order_helper |
| Field._order_helper += 1 |
|
|
| @property |
| def name(self): |
| try: |
| return self._name |
| except AttributeError: |
| log.error("The name attribute has not been set for this field. " |
| "Call set_name at class creation time.") |
| raise |
|
|
| def set_name(self, name): |
| self._name = name |
| return self |
|
|
| def __get__(self, instance, instance_type): |
| try: |
| if instance is None: |
| val = getattr(instance_type, KEY_OVERRIDES_MAP)[self.name] |
| else: |
| val = instance.__dict__[self.name] |
| except AttributeError: |
| log.error("The name attribute has not been set for this field.") |
| raise AttributeError("The name attribute has not been set for this field.") |
| except KeyError: |
| if self.default is NULL: |
| raise AttributeError(f"A value for {self.name} has not been set") |
| else: |
| val = maybecall(self.default) |
| if val is None and not self.nullable: |
| |
| raise AttributeError(f"The {self.name} field has been deleted.") |
| return self.unbox(instance, instance_type, val) |
|
|
| def __set__(self, instance, val): |
| if self.immutable and instance._initd: |
| raise AttributeError(f"The {self.name} field is immutable.") |
| |
| |
| instance.__dict__[self.name] = self.validate( |
| instance, |
| self.box(instance, instance.__class__, val), |
| ) |
|
|
| def __delete__(self, instance): |
| if self.immutable and instance._initd: |
| raise AttributeError(f"The {self.name} field is immutable.") |
| elif self.required: |
| raise AttributeError(f"The {self.name} field is required and cannot be deleted.") |
| elif not self.nullable: |
| |
| |
| |
| |
| instance.__dict__[self.name] = None |
| else: |
| instance.__dict__.pop(self.name, None) |
|
|
| def box(self, instance, instance_type, val): |
| return val |
|
|
| def unbox(self, instance, instance_type, val): |
| return val |
|
|
| def dump(self, instance, instance_type, val): |
| return val |
|
|
| def validate(self, instance, val): |
| """ |
| |
| Returns: |
| True: if val is valid |
| |
| Raises: |
| ValidationError |
| """ |
| |
| if isinstance(val, self._type) and (self._validation is None or self._validation(val)): |
| return val |
| elif val is NULL and not self.required: |
| return val |
| elif val is None and self.nullable: |
| return val |
| else: |
| raise ValidationError(getattr(self, 'name', 'undefined name'), val) |
|
|
| @property |
| def required(self): |
| return self._required |
|
|
| @property |
| def type(self): |
| return self._type |
|
|
| @property |
| def default(self): |
| return self._default |
|
|
| @property |
| def in_dump(self): |
| return self._in_dump |
|
|
| @property |
| def default_in_dump(self): |
| return self._default_in_dump |
|
|
| @property |
| def nullable(self): |
| return self.is_nullable |
|
|
| @property |
| def is_nullable(self): |
| return self._nullable |
|
|
| @property |
| def immutable(self): |
| return self._immutable |
|
|
|
|
| class BooleanField(Field): |
| _type = bool |
|
|
| def box(self, instance, instance_type, val): |
| return None if val is None else bool(val) |
|
|
|
|
| BoolField = BooleanField |
|
|
|
|
| class IntegerField(Field): |
| _type = int |
|
|
|
|
| IntField = IntegerField |
|
|
|
|
| class NumberField(Field): |
| _type = (int, float, complex) |
|
|
|
|
| class StringField(Field): |
| _type = str |
|
|
| def box(self, instance, instance_type, val): |
| return str(val) if isinstance(val, NumberField._type) else val |
|
|
|
|
| class DateField(Field): |
| _type = datetime |
|
|
| def box(self, instance, instance_type, val): |
| try: |
| return isoparse(val) if isinstance(val, str) else val |
| except ValueError as e: |
| raise ValidationError(val, msg=e) |
|
|
| def dump(self, instance, instance_type, val): |
| return None if val is None else val.isoformat() |
|
|
|
|
| class EnumField(Field): |
|
|
| def __init__(self, enum_class, default=NULL, required=True, validation=None, |
| in_dump=True, default_in_dump=True, nullable=False, immutable=False, aliases=()): |
| if not issubclass(enum_class, Enum): |
| raise ValidationError(None, msg="enum_class must be an instance of Enum") |
| self._type = enum_class |
| super().__init__( |
| default, required, validation, in_dump, default_in_dump, nullable, immutable, aliases |
| ) |
|
|
| def box(self, instance, instance_type, val): |
| if val is None: |
| |
| return None |
| try: |
| |
| return self._type(val) |
| except ValueError as e1: |
| try: |
| |
| return self._type[val] |
| except KeyError: |
| raise ValidationError(val, msg=e1) |
|
|
| def dump(self, instance, instance_type, val): |
| return None if val in (None, NULL) else val.value |
|
|
|
|
| class ListField(Field): |
| _type = tuple |
|
|
| def __init__(self, element_type, default=NULL, required=True, validation=None, |
| in_dump=True, default_in_dump=True, nullable=False, immutable=False, aliases=()): |
| self._element_type = element_type |
| super().__init__( |
| default, required, validation, in_dump, default_in_dump, nullable, immutable, aliases |
| ) |
|
|
| def box(self, instance, instance_type, val): |
| if val is None: |
| return None |
| elif isinstance(val, str): |
| raise ValidationError( |
| f"Attempted to assign a string to ListField {self.name}" |
| ) |
| elif isiterable(val): |
| et = self._element_type |
| if isinstance(et, type) and issubclass(et, Entity): |
| return self._type(v if isinstance(v, et) else et(**v) for v in val) |
| else: |
| return deepfreeze(val) if self.immutable else self._type(val) |
| else: |
| raise ValidationError( |
| val, msg=f"Cannot assign a non-iterable value to {self.name}" |
| ) |
|
|
| def unbox(self, instance, instance_type, val): |
| return self._type() if val is None and not self.nullable else val |
|
|
| def dump(self, instance, instance_type, val): |
| if isinstance(self._element_type, type) and issubclass(self._element_type, Entity): |
| return self._type(v.dump() for v in val) |
| else: |
| return val |
|
|
| def validate(self, instance, val): |
| val = super().validate(instance, val) |
| if val: |
| et = self._element_type |
| self._type(Raise(ValidationError(self.name, el, et)) for el in val |
| if not isinstance(el, et)) |
| return val |
|
|
|
|
| class MutableListField(ListField): |
| _type = list |
|
|
|
|
| class MapField(Field): |
| _type = frozendict |
|
|
| def __init__( |
| self, |
| default=NULL, |
| required=True, |
| validation=None, |
| in_dump=True, |
| default_in_dump=True, |
| nullable=False, |
| immutable=True, |
| aliases=(), |
| ): |
| super().__init__( |
| default, required, validation, in_dump, default_in_dump, nullable, immutable, aliases |
| ) |
|
|
| def box(self, instance, instance_type, val): |
| |
| if val is None: |
| return self._type() |
| elif isiterable(val): |
| val = deepfreeze(val) |
| if not isinstance(val, Mapping): |
| raise ValidationError( |
| val, msg=f"Cannot assign a non-iterable value to {self.name}" |
| ) |
| return val |
| else: |
| raise ValidationError( |
| val, msg=f"Cannot assign a non-iterable value to {self.name}" |
| ) |
|
|
|
|
| class ComposableField(Field): |
|
|
| def __init__(self, field_class, default=NULL, required=True, validation=None, |
| in_dump=True, default_in_dump=True, nullable=False, immutable=False, aliases=()): |
| self._type = field_class |
| super().__init__( |
| default, required, validation, in_dump, default_in_dump, nullable, immutable, aliases |
| ) |
|
|
| def box(self, instance, instance_type, val): |
| if val is None: |
| return None |
| if isinstance(val, self._type): |
| return val |
| else: |
| |
| try: |
| |
| if hasattr(val, 'pop'): |
| val['slf'] = val.pop('self') |
| except KeyError: |
| pass |
| if isinstance(val, self._type): |
| return val if isinstance(val, self._type) else self._type(**val) |
| elif isinstance(val, Mapping): |
| return self._type(**val) |
| elif isinstance(val, Sequence) and not isinstance(val, str): |
| return self._type(*val) |
| else: |
| return self._type(val) |
|
|
| def dump(self, instance, instance_type, val): |
| return None if val is None else val.dump() |
|
|
|
|
| class EntityType(type): |
|
|
| @staticmethod |
| def __get_entity_subclasses(bases): |
| try: |
| return [base for base in bases if issubclass(base, Entity) and base is not Entity] |
| except NameError: |
| |
| return () |
|
|
| def __new__(mcs, name, bases, dct): |
| |
| |
| non_field_keys = ( |
| key |
| for key, value in dct.items() |
| if not isinstance(value, Field) and not key.startswith("__") |
| ) |
| entity_subclasses = EntityType.__get_entity_subclasses(bases) |
| if entity_subclasses: |
| keys_to_override = [key for key in non_field_keys |
| if any(isinstance(base.__dict__.get(key), Field) |
| for base in entity_subclasses)] |
| dct[KEY_OVERRIDES_MAP] = {key: dct.pop(key) for key in keys_to_override} |
| else: |
| dct[KEY_OVERRIDES_MAP] = {} |
|
|
| return super().__new__(mcs, name, bases, dct) |
|
|
| def __init__(cls, name, bases, attr): |
| super().__init__(name, bases, attr) |
|
|
| fields = odict() |
| _field_sort_key = lambda x: x[1]._order_helper |
| for clz in reversed(type.mro(cls)): |
| clz_fields = ( |
| (name, field.set_name(name)) |
| for name, field in clz.__dict__.items() |
| if isinstance(field, Field) |
| ) |
| fields.update(sorted(clz_fields, key=_field_sort_key)) |
|
|
| cls.__fields__ = frozendict(fields) |
| if hasattr(cls, '__register__'): |
| cls.__register__() |
|
|
| def __call__(cls, *args, **kwargs): |
| instance = super().__call__(*args, **kwargs) |
| setattr(instance, f"_{cls.__name__}__initd", True) |
| return instance |
|
|
| @property |
| def fields(cls): |
| return cls.__fields__.keys() |
|
|
|
|
| class Entity(metaclass=EntityType): |
| __fields__ = odict() |
| _lazy_validate = False |
|
|
| def __init__(self, **kwargs): |
| for key, field in self.__fields__.items(): |
| try: |
| setattr(self, key, kwargs[key]) |
| except KeyError: |
| alias = next((ls for ls in field._aliases if ls in kwargs), None) |
| if alias is not None: |
| setattr(self, key, kwargs[alias]) |
| elif key in getattr(self, KEY_OVERRIDES_MAP): |
| |
| setattr(self, key, getattr(self, KEY_OVERRIDES_MAP)[key]) |
| elif field.required and field.default is NULL: |
| raise ValidationError( |
| key, |
| msg="{} requires a {} field. Instantiated with " |
| "{}".format(self.__class__.__name__, key, kwargs), |
| ) |
| except ValidationError: |
| if kwargs[key] is not None or field.required: |
| raise |
| if not self._lazy_validate: |
| self.validate() |
|
|
| @classmethod |
| def from_objects(cls, *objects, **override_fields): |
| """Construct a new object of type ``cls`` from existing objects or dicts. |
| |
| Allows the creation of new objects of concrete :class:`Entity` subclasses by |
| combining information from several sources. This can be any combination of |
| objects and dictionaries passed in as positional arguments. When looking for |
| the value of the fields of the :class:`Entity` subclass, the first object |
| that provides an attribute (or, in the case of a dict an entry) that has the |
| name of the field or one of its aliases will take precedence. Any keyword |
| arguments passed in will override this and take precedence. |
| |
| Args: |
| cls(:class:`Entity` subclass): The class to create, usually determined by call, e.g. ``PrefixRecord.from_objects(...)``. |
| *objects(tuple(object or dict)): Any combination of objects and dicts in order of decending precedence. |
| **override_fields(dict(str, object)): Any individual fields overriding possible contents from ``*objects``. |
| """ |
| init_vars = {} |
| search_maps = tuple(AttrDict(o) if isinstance(o, dict) else o |
| for o in ((override_fields,) + objects)) |
| for key, field in cls.__fields__.items(): |
| try: |
| init_vars[key] = find_or_raise(key, search_maps, field._aliases) |
| except AttributeError: |
| pass |
|
|
| return cls(**init_vars) |
|
|
| @classmethod |
| def from_json(cls, json_str): |
| return cls(**json.loads(json_str)) |
|
|
| @classmethod |
| def load(cls, data_dict): |
| return cls(**data_dict) |
|
|
| def validate(self): |
| |
| try: |
| reduce( |
| lambda _, name: getattr(self, name), |
| (name for name, field in self.__fields__.items() if field.required), |
| ) |
| except TypeError as e: |
| if str(e) == "reduce() of empty sequence with no initial value": |
| pass |
| except AttributeError as e: |
| raise ValidationError(None, msg=e) |
|
|
| def __repr__(self): |
| def _valid(key): |
| |
| |
| |
| if '__' in key: |
| return False |
| try: |
| getattr(self, key) |
| return True |
| except AttributeError: |
| return False |
|
|
| def _val(key): |
| val = getattr(self, key) |
| return repr(val.value) if isinstance(val, Enum) else repr(val) |
|
|
| def _sort_helper(key): |
| field = self.__fields__.get(key) |
| return field._order_helper if field is not None else -1 |
|
|
| kwarg_str = ", ".join( |
| f"{key}={_val(key)}" for key in sorted(self.__dict__, key=_sort_helper) if _valid(key) |
| ) |
| return f"{self.__class__.__name__}({kwarg_str})" |
|
|
| @classmethod |
| def __register__(cls): |
| pass |
|
|
| def json(self, indent=None, separators=None, **kwargs): |
| return json.dumps(self, indent=indent, separators=separators, **kwargs) |
|
|
| def pretty_json(self, indent=2, separators=(',', ': '), **kwargs): |
| return json.dumps(self, indent=indent, separators=separators, **kwargs) |
|
|
| def dump(self): |
| return odict((field.name, field.dump(self, self.__class__, value)) |
| for field, value in ((field, getattr(self, field.name, NULL)) |
| for field in self.__dump_fields()) |
| if value is not NULL and not (value is field.default |
| and not field.default_in_dump)) |
|
|
| @classmethod |
| def __dump_fields(cls): |
| if "__dump_fields_cache" not in cls.__dict__: |
| cls.__dump_fields_cache = tuple( |
| field for field in cls.__fields__.values() if field.in_dump |
| ) |
| return cls.__dump_fields_cache |
|
|
| def __eq__(self, other): |
| if self.__class__ != other.__class__: |
| return False |
| rando_default = 19274656290 |
| return all(getattr(self, field, rando_default) == getattr(other, field, rando_default) |
| for field in self.__fields__) |
|
|
| def __hash__(self): |
| return sum(hash(getattr(self, field, None)) for field in self.__fields__) |
|
|
| @property |
| def _initd(self): |
| return getattr(self, f"_{self.__class__.__name__}__initd", None) |
|
|
|
|
| class ImmutableEntity(Entity): |
|
|
| def __setattr__(self, attribute, value): |
| if self._initd: |
| raise AttributeError( |
| f"Assignment not allowed. {self.__class__.__name__} is immutable." |
| ) |
| super().__setattr__(attribute, value) |
|
|
| def __delattr__(self, item): |
| if self._initd: |
| raise AttributeError(f"Deletion not allowed. {self.__class__.__name__} is immutable.") |
| super().__delattr__(item) |
|
|
|
|
| class DictSafeMixin: |
|
|
| def __getitem__(self, item): |
| return getattr(self, item) |
|
|
| def __setitem__(self, key, value): |
| setattr(self, key, value) |
|
|
| def __delitem__(self, key): |
| delattr(self, key) |
|
|
| def get(self, item, default=None): |
| return getattr(self, item, default) |
|
|
| def __contains__(self, item): |
| value = getattr(self, item, None) |
| if value is None: |
| return False |
| field = self.__fields__[item] |
| if isinstance(field, (MapField, ListField)): |
| return len(value) > 0 |
| return True |
|
|
| def __iter__(self): |
| for key in self.__fields__: |
| if key in self: |
| yield key |
|
|
| def items(self): |
| for key in self.__fields__: |
| if key in self: |
| yield key, getattr(self, key) |
|
|
| def copy(self): |
| return self.__class__(**self.dump()) |
|
|
| def setdefault(self, key, default_value): |
| if key not in self: |
| setattr(self, key, default_value) |
|
|
| def update(self, E=None, **F): |
| |
| |
| |
| |
| if E is not None: |
| try: |
| for k, v in E.items(): |
| self[k] = v |
| except AttributeError: |
| for k, v in E: |
| self[k] = v |
| for k in F: |
| self[k] = F[k] |
|
|
|
|
| deprecated.constant( |
| "26.3", |
| "26.9", |
| "EntityEncoder", |
| json.CondaJSONEncoder, |
| addendum="Use `conda.common.serialize.json.CondaJSONEncoder` instead.", |
| ) |
|
|