Skip to main content
Help improve PyPI by participating in a 5-minute user interface survey!

Validation and parsing library

Project Description

Build status Gitter Downloads Downloads

Ultimate transformation library that supports validation, contexts and aiohttp.

Trafaret is rigid and powerful lib to work with foreign data, configs etc. It provides simple way to check anything, and convert it accordingly to your needs.

It have shortcut syntax and ability to express anything that you can code:

>>> from trafaret.constructor import construct
>>> validator = construct({'a': int, 'b': [str]})
>>> validator({'a': 5, 'b': ['lorem', 'ipsum']})
{'a': 5, 'b': ['lorem', 'ipsum']}

>>> validator({'a': 5, 'b': ['gorky', 9]})
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Users/mkrivushin/w/trafaret/trafaret/__init__.py", line 204, in __call__
    return self.check(val)
  File "/Users/mkrivushin/w/trafaret/trafaret/__init__.py", line 144, in check
    return self._convert(self.check_and_return(value))
  File "/Users/mkrivushin/w/trafaret/trafaret/__init__.py", line 1105, in check_and_return
    raise DataError(error=errors, trafaret=self)
trafaret.DataError: {'b': DataError({1: DataError(value is not a string)})}

Read The Docs hosted documentation <http://trafaret.readthedocs.org/en/latest/> or look to the docs/api/intro.rst for start.

Trafaret can even generate Trafarets instances to build transformators from json, like in json schema implementation Trafaret Schema

New

  • converters and convert=False are deleted in favor of And and &
  • String parameter regex deleted in favor of Regexp and RegexpRaw usage
  • new OnError to customize error message
  • context=something argument for __call__ and check Trafaret methods. Supported by Or, And, Forward etc.
  • new customizable method transform like change_and_return but takes context= arg
  • new trafaret_instance.async_check method that works with await

Doc

For simple example what can be done:

import datetime
import trafaret as t

date = t.Dict(year=t.Int, month=t.Int, day=t.Int) >> (lambda d: datetime.datetime(**d))
assert date.check({'year': 2012, 'month': 1, 'day': 12}) == datetime.datetime(2012, 1, 12)

Work with regex:

>>> c = t.String(regex=r'^name=(\w+)$') >> (lambda m: m.groups()[0])
>>> c.check('name=Jeff')
'Jeff'

Rename dict keys:

>>> c = t.Dict(t.Key('uNJ') >> 'user_name': t.String})
>>> c.check({'uNJ': 'Adam'})
{'user_name': 'Adam'}

Arrow date checking:

import arrow

def check_datetime(str):
    try:
        return arrow.get(str).naive
    except arrow.parser.ParserError:
        return t.DataError('value is not in proper date/time format')

Yes, you can write trafarets that simple.

Release history Release notifications

History Node

2.0.0a1

This version
History Node

1.1.1

History Node

1.1.0

History Node

1.0.4a2

History Node

1.0.4a1

History Node

1.0.2

History Node

1.0.1

History Node

1.0.0

History Node

0.12.3

History Node

0.12.1.dev0

History Node

0.12.0

History Node

0.11.3

History Node

0.11.2

History Node

0.11.1

History Node

0.11.0

History Node

0.11.dev4

History Node

0.11.dev3

History Node

0.11.dev2

History Node

0.11.dev1

History Node

0.10.4

History Node

0.10.3

History Node

0.10.2

History Node

0.10.1

History Node

0.10.0

History Node

0.9.1

History Node

0.9.0

History Node

0.8.1

History Node

0.8.0

History Node

0.7.6

History Node

0.7.5

History Node

0.7.4

History Node

0.7.3

History Node

0.7.2

History Node

0.7.1

History Node

0.7.0

History Node

0.6.4

History Node

0.6.3

History Node

0.6.2

History Node

0.6.1

History Node

0.6.0

History Node

0.5.5

History Node

0.5.4

History Node

0.5.3

History Node

0.5.2

History Node

0.5.1

History Node

0.5.0

History Node

0.4.8

History Node

0.4.7

History Node

0.4.6

History Node

0.4.5

History Node

0.4.4

History Node

0.4.3

History Node

0.4.2

History Node

0.4.1

History Node

0.4.0

History Node

0.3.91

History Node

0.3.82

History Node

0.3.81

History Node

0.3.9

History Node

0.3.8

History Node

0.3.7

History Node

0.3.5

History Node

0.3.4

History Node

0.3.3

History Node

0.3.2

History Node

0.3.1

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Filename, size & hash SHA256 hash help File type Python version Upload date
trafaret-1.1.1-py3-none-any.whl (26.6 kB) Copy SHA256 hash SHA256 Wheel 3.6 Feb 7, 2018
trafaret-1.1.1.tar.gz (22.5 kB) Copy SHA256 hash SHA256 Source None Feb 7, 2018

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging CloudAMQP CloudAMQP RabbitMQ AWS AWS Cloud computing Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page