PyCont
Validate and genereate pythpon objects from templates. Library is powered by Trafaret and helps to validate and genereate data from template.
Documentation
https://pycont.readthedocs.io/en/latest/index.html
Usage
pip install pycontSimple data template
>>> from pycont import Template, Contract
>>> import trafaret as t
>>> contract = Contract(Template(t.Int()))
>>> print(contract(42))
42
>>> print(contract('test'))
Traceback (most recent call last):
...
ValueError: Invalid value: value can't be converted to intSimple list template
>>> from pycont import Template, Contract
>>> import trafaret as t
>>> contract = Contract([
... Template(t.Int())
...])
>>> print(contract([42]))
[42]
>>> print(contract([1, 2, 3, 4, 5]))
[1, 2, 3, 4, 5]
>>> print(contract([1, 2, 3, 'error']))
Traceback (most recent call last):
...
ValueError: Invalid value: value can't be converted to intStatic list template
>>> from pycont import Template, Contract
>>> import trafaret as t
>>> contract = Contract([
... Template(t.Int()),
... Template(t.String()),
... Template(t.Float()),
...])
>>> print(contract([42, 'test', 12.5]))
[42, 'test', 12.5]Dict template
>>> from pycont import Template, Contract
>>> import trafaret as t
>>> contract = Contract(Template(t.Int(), default=42))
>>> print(contract('error'))
42
>>> contract = Contract({
... 'id': Template(t.Int()),
... 'value': Template(t.String()),
...})
# Key 'key' not contains in template
>>> print(contract({'id': 1, 'value': 'test', 'key': None}))
{'id': 1, 'value': 'test'}Deafult value
pycont.Template contains an optional argument default (the default type must be valid to Tremplate checker). If the argument is set, then if the check fails, this value will be returned.
>>> from pycont import Template, Contract
>>> import trafaret as t
>>> contract = Contract({
... 'id': Template(t.Int()),
... 'value': Template(t.String(), default='None'), # 'None' is a string
...})
>>> print(contract({'id': 1, 'key': None})) # key 'value' is not set
{'id': 1, 'value': 'None'}
