https://github.com/selik/destructure

Easy declarative schema validation with optional name-binding. Gives Python a switch/case.
https://github.com/selik/destructure

Last synced: 2 months ago
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Easy declarative schema validation with optional name-binding. Gives Python a switch/case.

• Host: GitHub
• URL: https://github.com/selik/destructure
• Owner: selik
• License: mit
• Created: 2016-05-28T01:39:55.000Z (over 8 years ago)
• Default Branch: master
• Last Pushed: 2016-08-24T13:53:22.000Z (over 8 years ago)
• Last Synced: 2024-08-03T23:15:26.744Z (5 months ago)
• Language: Python
• Homepage:
• Size: 23.4 KB
• Stars: 9
• Watchers: 2
• Forks: 0
• Open Issues: 3
• Metadata Files:
  • Readme: README.rst
  • License: LICENSE

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• awesome-python-models - destructure - Easy declarative schema validation with optional name-binding. (Data validation)

README

        
#################

   destructure

#################

Easy declarative schema validation with optional name-binding.

.. code:: python

    >>> from destructure import Binding, match

    >>>

    >>> o = Binding()

    >>> schema = {

    ...     'string': str,

    ...     'any': ...,

    ...     'binding': o.name,

    ...     'sequence': [1, 2, ...],

    ...     'mapping': {'a': int, ...: ...},

    ... }

    >>> data = {

    ...     'string': 'a',

    ...     'any': 5j,

    ...     'binding': 42,

    ...     'sequence': [1, 2, 3, 4],

    ...     'mapping': {'a': 1, 'b': 2, 'c': 3},

    ... }

    >>> guard = lambda : o.name > 10

    >>> data == match(schema, data, guard)

    True

    >>> o.name

    42

Pick between several schemas with a handy ``Switch.case``.

.. code:: python

    >>> from destructure import Binding, Switch

    >>>

    >>> o = Binding()

    >>> schema1 = [1, o.x, 3]

    >>> schema2 = [2, 4, o.x]

    >>>

    >>> s = Switch([2, 4, 6])

    >>> if s.case(schema1):

    ...     print(o.x)

    ... elif s.case(schema2):

    ...     print(o.x)

    ... else:

    ...     print('otherwise')

    6

Schemas may include many kinds of objects, though to make use of

Ellipses or Binding, the class must support keyword arguments and

cannot be too strict with parameter type-checking.

.. code:: python

    >>> class Foo:

    ...     def __init__(self, bar):

    ...         self.bar = bar

    >>> bind = Binding()

    >>> schema = Foo(bar=bind.x)

    >>> result = match(schema, Foo(bar=1))

    >>> bind.x

    1

See some `example scripts`_ for a practical usage, in context.

.. _`example scripts`: http://github.com/selik/destructure/tree/master/examples