History#
23.2.1 (2023-11-18)#
23.2.0 (2023-11-17)#
Potentially breaking: skip attrs fields marked as
init=Falseby default. This change is potentially breaking for unstructuring. See here for instructions on how to restore the old behavior. (#40 #395)Potentially breaking:
cattrs.gen.make_dict_structure_fn()andcattrs.gen.typeddicts.make_dict_structure_fn()will use the values for thedetailed_validationandforbid_extra_keysparameters from the given converter by default now. If you’re using these functions directly, the old behavior can be restored by passing in the desired values directly. (#410 #411)Potentially breaking: The default union structuring strategy will also use fields annotated as
typing.Literalto help guide structuring. See here for instructions on how to restore the old behavior. (#391)Python 3.12 is now supported. Python 3.7 is no longer supported; use older releases there. (#424)
Implement the
union passthroughstrategy, enabling much richer union handling for preconfigured converters. Learn more here.Introduce the
use_class_methodsstrategy. Learn more here. (#405)The
omitparameter ofcattrs.override()is now of typebool | None(frombool).Noneis the new default and means to apply default cattrs handling to the attribute, which is to omit the attribute if it’s marked asinit=False, and keep it otherwise.Converters can now be initialized with custom fallback hook factories for un/structuring. (#331 #441)
Add support for
dateto preconfigured converters. (#420)Add support for
datetime.dates to the PyYAML preconfigured converter. (#393)Fix
format_exception()parameter working for recursive calls totransform_error. (#389)attrs aliases are now supported, although aliased fields still map to their attribute name instead of their alias by default when un/structuring. (#322 #391)
Fix TypedDicts with periods in their field names. (#376 #377)
Optimize and improve unstructuring of
Optional(unions of one type andNone). (#380 #381)Fix
format_exceptionandtransform_errortype annotations.Improve the implementation of
cattrs._compat.is_typeddict. The implementation is now simpler, and relies on fewer private implementation details fromtypingand typing_extensions. (#384)Improve handling of TypedDicts with forward references.
Speed up generated attrs and TypedDict structuring functions by changing their signature slightly. (#388)
Broaden
loads'type definition for the preconf orjson converter. (#400)AttributeValidationNoteandIterableValidationNoteare now picklable. (#408)Fix structuring
Finallists. (#412)Fix certain cases of structuring
Annotatedtypes. (#418)Fix the tagged union strategy to work with
forbid_extra_keys. (#402 #443)Use PDM instead of Poetry.
cattrs is now linted with Ruff.
Remove some unused lines in the unstructuring code. (#416)
Fix handling classes inheriting from non-generic protocols. (#374 #436)
The documentation Makefile now supports the
htmlviewandhtmllivetargets. (#442)cattrs is now published using PyPI Trusted Publishers, and
mainbranch commits are automatically deployed to Test PyPI.
23.1.2 (2023-06-02)#
Improve
typing_extensionsversion bound. (#372)
23.1.1 (2023-05-30)#
23.1.0 (2023-05-30)#
Introduce the
tagged_unionstrategy. (#318 #317)Introduce the
cattrs.transform_errorhelper function for formatting validation exceptions. (258 342)Add support for
typing.TypedDictandtyping_extensions.TypedDict. (#296 #364)Introduce
override.struct_hookandoverride.unstruct_hook. Learn more here. (#326)Fix generating structuring functions for types with angle brackets (
<>) and pipe symbols (|) in the name. (#319 #327)pathlib.Pathis now supported by default. (#81)Add
cbor2serialization library to thecattrs.preconfpackage.Add optional dependencies for
cattrs.preconfthird-party libraries. (#337)All preconf converters now allow overriding the default
unstruct_collection_overridesinmake_converter. (#350 #353)Subclasses structuring and unstructuring is now supported via a custom
include_subclassesstrategy. (#312)Add support for
typing_extensions.Annotatedwhen the python version is less than3.9. (#366)Add unstructuring and structuring support for the standard library
deque. (#355)
22.2.0 (2022-10-03)#
Potentially breaking:
cattrs.Converterhas been renamed tocattrs.BaseConverter, andcattrs.GenConvertertocattrs.Converter. TheGenConvertername is still available for backwards compatibility, but is deprecated. If you were depending on functionality specific to the oldConverter, change your import tofrom cattrs import BaseConverter.NewTypes are now supported by the
cattrs.Converter. (#255 #94 #297)cattrs.Converterandcattrs.BaseConvertercan now copy themselves using thecopymethod. (#284)Python 3.11 support.
cattrs now supports un/structuring
kw_onlyfields on attrs classes into/from dictionaries. (#247)PyPy support (and tests, using a minimal Hypothesis profile) restored. (#253)
Fix propagating the
detailed_validationflag to mapping and counter structuring generators.Fix
typing.Setapplying too broadly when used with theGenConverter.unstruct_collection_overridesparameter on Python versions below 3.9. Switch totyping.AbstractSeton those versions to restore the old behavior. (#264)Uncap the required Python version, to avoid problems detailed here (#275)
Fix
Converter.register_structure_hook_factoryandcattrs.gen.make_dict_unstructure_fntype annotations. (#281)Expose all error classes in the
cattr.errorsnamespace. Note that it is deprecated, just usecattrs.errors. (#252)Fix generating structuring functions for types with quotes in the name. (#291 #277)
Fix usage of notes for the final version of PEP 678, supported since
exceptiongroup>=1.0.0rc4. (#303)
22.1.0 (2022-04-03)#
cattrs now uses the CalVer versioning convention.
cattrs now has a detailed validation mode, which is enabled by default. Learn more here. The old behavior can be restored by creating the converter with
detailed_validation=False.attrs and dataclass structuring is now ~25% faster.
Fix an issue structuring bare
typing.Lists on Pythons lower than 3.9. (#209)Fix structuring of non-parametrized containers like
list/dict/...on Pythons lower than 3.9. (#218)Fix structuring bare
typing.Tupleon Pythons lower than 3.9. (#218)Fix a wrong
AttributeErrorof an missing__parameters__attribute. This could happen when inheriting certain generic classes – for exampletyping.*classes are affected. (#217)Fix structuring of
enum.Enuminstances intyping.Literaltypes. (#231)Fix unstructuring all tuples - unannotated, variable-length, homogenous and heterogenous - to
list. (#226)For
forbid_extra_keysraise customForbiddenExtraKeyErrorinstead of genericException. (#225)All preconf converters now support
loadsanddumpsdirectly. See an example here.Fix mappings with byte keys for the orjson, bson and tomlkit converters. (#241)
1.10.0 (2022-01-04)#
Add PEP 563 (string annotations) support for dataclasses. (#195)
Fix handling of dictionaries with string Enum keys for bson, orjson, and tomlkit.
Rename the
cattr.gen.make_dict_unstructure_fn.omit_if_defaultparameter to_cattrs_omit_if_default, for consistency. Theomit_if_defaultparameters toGenConverterandoverrideare unchanged.Following the changes in attrs 21.3.0, add a
cattrspackage mirroring the existingcattrpackage. Both package names may be used as desired, and thecattrpackage isn’t going away.
1.9.0 (2021-12-06)#
Python 3.10 support, including support for the new union syntax (
A | BvsUnion[A, B]).The
GenConvertercan now properly structure generic classes with generic collection fields. (#149)omit=Truenow also affects generated structuring functions. (#166)cattr.gen.{make_dict_structure_fn, make_dict_unstructure_fn}now resolve type annotations automatically when PEP 563 is used. (#169)Protocols are now unstructured as their runtime types. (#177)
Fix an issue generating structuring functions with renaming and
_cattrs_forbid_extra_keys=True. (#190)
1.8.0 (2021-08-13)#
Fix
GenConvertermapping structuring for unannotated dicts on Python 3.8. (#151)The source code for generated un/structuring functions is stored in the
linecachecache, which enables more informative stack traces when un/structuring errors happen using theGenConverter. This behavior can optionally be disabled to save memory.Support using the attr converter callback during structure. By default, this is a method of last resort, but it can be elevated to the default by setting
prefer_attrib_converters=TrueonConverterorGenConverter. (#138)Fix structuring recursive classes. (#159)
Converters now support un/structuring hook factories. This is the most powerful and complex venue for customizing un/structuring. This had previously been an internal feature.
The Common Usage Examples documentation page now has a section on advanced hook factory usage.
cattr.overridenow supports theomitparameter, which makes cattrs skip the atribute entirely when unstructuring.The
cattr.preconf.bsonmodule is now tested against thebsonmodule bundled with thepymongopackage, because that package is much more popular than the standalone PyPIbsonpackage.
1.7.1 (2021-05-28)#
Literals are not supported on Python 3.9.0 (supported on 3.9.1 and later), so we skip importing them there. (#150)
1.7.0 (2021-05-26)#
cattr.global_converter(which providescattr.unstructure,cattr.structureetc.) is now an instance ofcattr.GenConverter.Literals are now supported and validated when structuring.Fix dependency metadata information for attrs. (#147)
Fix
GenConvertermapping structuring for unannotated dicts. (#148)
1.6.0 (2021-04-28)#
cattrs now uses Poetry.
GenConvertermapping structuring is now ~25% faster, and unstructuring heterogenous tuples is significantly faster.Add
cattr.preconf. This package contains modules for making converters for particular serialization libraries. We currently support the standard libraryjson, and third-partyujson,orjson,msgpack,bson,pyyamlandtomlkitlibraries.
1.5.0 (2021-04-15)#
Fix an issue with
GenConverterunstructuring attrs classes and dataclasses with generic fields. (#65)GenConverterhas support for easy overriding of collection unstructuring types (for example, unstructure all sets to lists) through itsunstruct_collection_overridesargument. (#137)Unstructuring mappings with
GenConverteris significantly faster.GenConvertersupports strict handling of unexpected dictionary keys through itsforbid_extra_keysargument. (#142)
1.4.0 (2021-03-21)#
Fix an issue with
GenConverterun/structuring hooks when a function hook is registered after the converter has already been used.Add support for
collections.abc.{Sequence, MutableSequence, Set, MutableSet}. These should be used on 3.9+ instead of theirtypingalternatives, which are deprecated. (#128)The
GenConverterwill unstructure iterables (list[T],tuple[T, ...],set[T]) using their type argument instead of the runtime class if its elements, if possible. These unstructuring operations are up to 40% faster. (#129)Flesh out
ConverterandGenConverterinitializer type annotations. (#131)Add support for
typing.Annotatedon Python 3.9+. cattrs will use the first annotation present. cattrs specific annotations may be added in the future. (#127)Add support for dataclasses. (#43)
1.3.0 (2021-02-25)#
cattrs now has a benchmark suite to help make and keep cattrs the fastest it can be. The instructions on using it can be found under the Benchmarking section in the docs. (#123)
Fix an issue unstructuring tuples of non-primitives. (#125)
cattrs now calls
attr.resolve_typeson attrs classes when registering un/structuring hooks.GenConverterstructuring and unstructuring of attrs classes is significantly faster.
1.2.0 (2021-01-31)#
converter.unstructurenow supports an optional parameter,unstructure_as, which can be used to unstructure something as a different type. Useful for unions.Improve support for union un/structuring hooks. Flesh out docs for advanced union handling. (#115)
Fix
GenConverterbehavior with inheritance hierarchies of attrs classes. ([#117](https://github.com/python-attrs/cattrs/pull/117 #116)Refactor
GenConverter.un/structure_attrs_fromdictintoGenConverter.gen_un/structure_attrs_fromdictto allow calling back toConverter.un/structure_attrs_fromdictwithout sideeffects. (#118)
1.1.2 (2020-11-29)#
1.1.1 (2020-10-30)#
Add metadata for supported Python versions. (#103)
1.1.0 (2020-10-29)#
Python 2, 3.5 and 3.6 support removal. If you need it, use a version below 1.1.0.
Python 3.9 support, including support for built-in generic types (
list[int]vstyping.List[int]).cattrs now includes functions to generate specialized structuring and unstructuring hooks. Specialized hooks are faster and support overrides (
omit_if_defaultandrename). See thecattr.genmodule.cattrs now includes a converter variant,
cattr.GenConverter, that automatically generates specialized hooks for attrs classes. This converter will become the default in the future.Generating specialized structuring hooks now invokes attr.resolve_types on a class if the class makes use of the new PEP 563 annotations.
cattrs now depends on attrs >= 20.1.0, because of
attr.resolve_types.Specialized hooks now support generic classes. The default converter will generate and use a specialized hook upon encountering a generic class.
1.0.0 (2019-12-27)#
attrs classes with private attributes can now be structured by default.
Structuring from dictionaries is now more lenient: extra keys are ignored.
cattrs has improved type annotations for use with Mypy.
Unstructuring sets and frozensets now works properly.
0.9.1 (2019-10-26)#
Python 3.8 support.
0.9.0 (2018-07-22)#
Python 3.7 support.
0.8.1 (2018-06-19)#
The disambiguation function generator now supports unions of attrs classes and NoneType.
0.8.0 (2018-04-14)#
Distribution fix.
0.7.0 (2018-04-12)#
Removed the undocumented
Converter.unstruct_stratproperty setter.Removed the ability to set the
Converter.structure_attrsinstance field.Some micro-optimizations were applied; a
structure(unstructure(obj))roundtrip is now up to 2 times faster.
0.6.0 (2017-12-25)#
Packaging fixes. (#17)
0.5.0 (2017-12-11)#
structure/unstructure now supports using functions as well as classes for deciding the appropriate function.
added
Converter.register_structure_hook_func, to register a function instead of a class for determining handler func.added
Converter.register_unstructure_hook_func, to register a function instead of a class for determining handler func.vendored typing is no longer needed, nor provided.
Attributes with default values can now be structured if they are missing in the input. (#15)
Optionalattributes can no longer be structured if they are missing in the input.cattr.typedremoved since the functionality is now present in attrs itself. Replace instances ofcattr.typed(type)withattr.ib(type=type).
0.4.0 (2017-07-17)#
Converter.loadsis nowConverter.structure, andConverter.dumpsis nowConverter.unstructure.Python 2.7 is supported.
Moved
cattr.typingtocattr.vendor.typingto support different vendored versions of typing.py for Python 2 and Python 3.Type metadata can be added to attrs classes using
cattr.typed.
0.3.0 (2017-03-18)#
Python 3.4 is no longer supported.
Introduced
cattr.typingfor use with Python versions 3.5.2 and 3.6.0.Minor changes to work with newer versions of
typing.Bare Optionals are not supported any more (use
Optional[Any]).Attempting to load unrecognized classes will result in a ValueError, and a helpful message to register a loads hook.
Loading attrs classes is now documented.
The global converter is now documented.
cattr.loads_attrs_fromtupleandcattr.loads_attrs_fromdictare now exposed.
0.2.0 (2016-10-02)#
Tests and documentation.
0.1.0 (2016-08-13)#
First release on PyPI.