README.md

Formalist Validation

Data validation library for Formalist based on predicate logic.

The scope of the library is very simple. It tests a value against a given schema and returns an array of relevant error messages.

Usage

import validation from 'formalist-validation'

// Define a schema
const schema = {
  "filled": true,
  "min_size": 2,
  "max_size": 3,
}

// Curry validator with the schema
const validator = validation(schema)

// Test
validator([1])
// => ['size cannot be less than 2']
validator([1,2])
// => []
validator([1,2,3])
// => []
validator([1,2,3,4])
// => ['size cannot be greater than 3']

View the full list of available predicates to see what else you can test.

Caveats

• Tests will only be run if there’s a value to test or the schema specifies that to test that the value is 'filled'.
• All the predicate tests are run as logical ANDs. There’s no support for more complex logic at at the moment.

TODO

• Allow custom validations to be injected
• i18n support