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Editing: interfaces.cpython-38.pyc
U ��]� � @ s� d Z ddlZddlZddlZddlmZmZ zddlmZm Z W n$ e k rd ddlmZm Z Y nX e�ej �G dd� de��ZdS )zJOSE interfaces.� N)�errors�util)�Sequence�Mappingc @ s\ e Zd ZdZejdd� �Zdd� Zej dd� �Z edd � �Zd d� Z dd � Zedd� �ZdS )�JSONDeSerializablea� Interface for (de)serializable JSON objects. Please recall, that standard Python library implements :class:`json.JSONEncoder` and :class:`json.JSONDecoder` that perform translations based on respective :ref:`conversion tables <conversion-table>` that look pretty much like the one below (for complete tables see relevant Python documentation): .. _conversion-table: ====== ====== JSON Python ====== ====== object dict ... ... ====== ====== While the above **conversion table** is about translation of JSON documents to/from the basic Python types only, :class:`JSONDeSerializable` introduces the following two concepts: serialization Turning an arbitrary Python object into Python object that can be encoded into a JSON document. **Full serialization** produces a Python object composed of only basic types as required by the :ref:`conversion table <conversion-table>`. **Partial serialization** (accomplished by :meth:`to_partial_json`) produces a Python object that might also be built from other :class:`JSONDeSerializable` objects. deserialization Turning a decoded Python object (necessarily one of the basic types as required by the :ref:`conversion table <conversion-table>`) into an arbitrary Python object. Serialization produces **serialized object** ("partially serialized object" or "fully serialized object" for partial and full serialization respectively) and deserialization produces **deserialized object**, both usually denoted in the source code as ``jobj``. Wording in the official Python documentation might be confusing after reading the above, but in the light of those definitions, one can view :meth:`json.JSONDecoder.decode` as decoder and deserializer of basic types, :meth:`json.JSONEncoder.default` as serializer of basic types, :meth:`json.JSONEncoder.encode` as serializer and encoder of basic types. One could extend :mod:`json` to support arbitrary object (de)serialization either by: - overriding :meth:`json.JSONDecoder.decode` and :meth:`json.JSONEncoder.default` in subclasses - or passing ``object_hook`` argument (or ``object_hook_pairs``) to :func:`json.load`/:func:`json.loads` or ``default`` argument for :func:`json.dump`/:func:`json.dumps`. Interestingly, ``default`` is required to perform only partial serialization, as :func:`json.dumps` applies ``default`` recursively. This is the idea behind making :meth:`to_partial_json` produce only partial serialization, while providing custom :meth:`json_dumps` that dumps with ``default`` set to :meth:`json_dump_default`. To make further documentation a bit more concrete, please, consider the following imaginatory implementation example:: class Foo(JSONDeSerializable): def to_partial_json(self): return 'foo' @classmethod def from_json(cls, jobj): return Foo() class Bar(JSONDeSerializable): def to_partial_json(self): return [Foo(), Foo()] @classmethod def from_json(cls, jobj): return Bar() c C s t � �dS )a� Partially serialize. Following the example, **partial serialization** means the following:: assert isinstance(Bar().to_partial_json()[0], Foo) assert isinstance(Bar().to_partial_json()[1], Foo) # in particular... assert Bar().to_partial_json() != ['foo', 'foo'] :raises josepy.errors.SerializationError: in case of any serialization error. :returns: Partially serializable object. N)�NotImplementedError��self� r �3/usr/lib/python3/dist-packages/josepy/interfaces.py�to_partial_jsonk s z"JSONDeSerializable.to_partial_jsonc s � fdd�� � | �S )aD Fully serialize. Again, following the example from before, **full serialization** means the following:: assert Bar().to_json() == ['foo', 'foo'] :raises josepy.errors.SerializationError: in case of any serialization error. :returns: Fully serialized object. c s� t | t�r� | �� �S t | tj�r&| S t | t�rB� fdd�| D �S t | t�rbt� fdd�| D ��S t | t�r�t � fdd�t� | �D ��S | S d S )Nc s g | ]}� |��qS r r ��.0Zsubobj�� _serializer r � <listcomp>� s zBJSONDeSerializable.to_json.<locals>._serialize.<locals>.<listcomp>c 3 s | ]}� |�V qd S �Nr r r r r � <genexpr>� s zAJSONDeSerializable.to_json.<locals>._serialize.<locals>.<genexpr>c 3 s"