• Python 3.6+

Installation & Upgrade

pip install fastvalidate --upgrade

Dictionary Validation

from fastvalidate import Validator

validator = Validator({
    'first_name': 'Mo',
    'last_name': None,
    'age': '5',
    'email': '[email protected]',
    'website': 'yup',
    'languages': ['en', 'fa'],
}, {
    'first_name': 'required|min:3',
    'last_name': 'required|min:3',
    'age': 'required|numeric|gt:10|lt:120',
    'email': 'required|email',
    'website': 'required|url',
    'languages': 'required|list|min:3'

# {
#     'first_name': 'Field length must be at least 3 characters',
#     'last_name': 'Field is required',
#     'age': 'Field must be greater than 10',
#     'email': 'Field must be email',
#     'website': 'Field must be url',
#     'languages': 'Field must have at least 3 items'
# }

Pydantic Validation

from fastvalidate import BaseModel

class User(BaseModel):
    email: str
    website: str

    class Config:
        rules = dict(

user = User(email='whatever', website='whoever')
# ValidationError
# [
#     dict(loc=('email',), msg='Field must be email', type='value_error'),
#     dict(loc=('website',), msg='Field must be url', type='value_error')
# ]

Available Rules

Type Applicable On signature
Boolean string, boolean bool, boolean
Numeric string, integer numeric, int, integer
List string(json), list list, array
Dictionary string(json), dict dict
Email string email
Password string password
RegEx string regex:<pattern>
URL string url
Length string, integer, float, list, dict len:<length>, length:<length>
Min string, integer, float, list, dict min:<threshold>
Max string, integer, float, list, dict max:<threshold>
Choice string choice:<x>,<y>,<z> in:<x>,<y>,<z>
Greater Than int gt:<threshold>
Greater Than Equal int gte:<threshold>
Less Than int lt:<threshold>
Less Than Equal int lte:<threshold>


# install pytest
pip install pytest

# run tests
python -m pytest


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