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Lean schema-enforcing objects

Project Description



Base library for defining lean “contract” models for Python.


This is an implementation of “models” similar to those you see in most ORMs / forms definition systems, but with the main goal of keeping things as simple as possible.

No metaclasses or descriptors are involved; no hackish code messing up with standard Python objects functionality either.

The idea is to have a “layered” library, providing the bare bones needed to define your own schemas, along with some nice helpers for common cases.

Use cases

  • API clients
  • ORMs
  • Forms

Example model definition

from contracts.core import Contract, BaseField

# Use BaseField to define your field types, eg. StringField and
# IntegerField.

class MyModel(BaseObject):
    first_name = StringField()
    last_name = StringField()
    age = IntegerField()

Then, create some library to make use of the schema somehow 😊.

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