PyValidator 0.0.4

PyValidator

schema is a library for validating Python data structures, such as those obtained from config-files, forms, external services or command-line parsing, converted from JSON/YAML (or something else) to Python data-types.

PyValidator is an (almost) drop-in replacement of Python Schema, written almost from scratch for the sake of better error handling.

Examples (From python schema)

Here is a quick example to get a feeling of schema, validating a list of entries with personal information:

>>> from pyvalidator import Validator, And, Use, Optional

>>> validator = Validator([{'name': And(str, len),
...                   'age':  And(Use(int), lambda n: 18 <= n <= 99),
...                   Optional('sex'): And(str, Use(str.lower),
...                                        lambda s: s in ('male', 'female'))}])

>>> data = [{'name': 'Sue', 'age': '28', 'sex': 'FEMALE'},
...         {'name': 'Sam', 'age': '42'},
...         {'name': 'Sacha', 'age': '20', 'sex': 'Male'}]

>>> validated = validator.validate(data)

>>> assert validated == [{'name': 'Sue', 'age': 28, 'sex': 'female'},
...                      {'name': 'Sam', 'age': 42},
...                      {'name': 'Sacha', 'age' : 20, 'sex': 'male'}]

If data is valid, Validator.validate will return the validated data (optionally converted with Use calls, see below).

If data is invalid, Schema will raise SchemaError exception.

Installation

Use pip or easy_install:

pip install pyvalidator

• pyvalidator is tested with Python 2.6, 2.7.

• pyvalitator follows semantic versioning.

How Validator validates data

Types

If Validator(...) encounters a type (such as int, str, object, etc.), it will check if the corresponding piece of data is an instance of that type, otherwise it will raise ErrorBucket.

>>> from pyvalidator import Validator

>>> Validator(int).validate(123)
123