react-nested-validation

react-nested-validation

A toolkit for performing nested validation of React forms.

Rationale

There is a diverse array of React packages designed to help render and validate forms. However there was no obvious choice that provided the following features:

• Ability to deeply nest forms and collate errors at the top level.

• Allow for complex validation rules.

• Unopinionated about how to render presentational components.

We found a need for a light weight validation toolkit that could be used with a variety of presentational frameworks, and so we made react-nested-validation.

Design

There are three main components:

• Forms.

• Validator functions.

• React component wrappers.

Forms are the main interface for designing both the validation, and the nested structure of your validation. Forms are ES6 classes that contain links to subforms, and allow for methods to be overidden in order to validate both fields and general form errors.

Validator functions are conveniences for performing common validation operations, e.g. required fields.

The React component wrappers are two higher-order components to help apply Forms to your presentational React comonents.

Basic example

import Form, {required} from 'react-nested-validation'

class MovieForm extends Form {
  fieldValidators = {
    title: required()
  }
}

import React from 'react'
import {asForm} from 'react-nested-validation'

@asForm({form: BasicForm})
class Movie extends React.Component {
  render() {
    const {form} = this.props
    const {values, errors, touched} = form
    return (
      <div>
        <input
          name="title"
          value={values.title}
        />
        <input
          name="year"
          value={values.year}
        />
      </div>
    )
  }
}

Nested example

import Form, {required} from 'react-nested-validation'

class DirectorForm extends Form {
  fieldValidators = {
    name: required()
  }
}

class MovieForm extends Form {
  fieldValidators = {
    title: required()
  }
  nested = {
    director: DirectorForm
  }
}

import React from 'react'
import {asForm} from 'react-nested-validation'

@asForm({form: SubForm})
class Sub extends React.Component {
  render() {
    const {form} = this.props
    const {values, errors, touched} = form
    // Render your form here.
  }
}

@asForm({form: SuperForm})
class Super extends React.Component {
  render() {
    const {form} = this.props
    const {values, errors, touched} = form
    return (
      <div>
        <Sub
          form={values.sub}
          prefix="sub"
        />
      </div>
    )
  }
}

Array example

import Form, {required} from 'react-nested-validation'

class MovieForm extends Form {
  fieldValidators = {
    title: required()
  }
}

class MovieListForm extends Form {
  nested = [
    MovieForm
  ]
}

import React from 'react'
import {asForm} from 'react-nested-validation'

@asForm({form: SubForm})
class Sub extends React.Component {
  render() {
    const {form} = this.props
    const {values, errors, touched} = form
    // Render your form here.
  }
}

@asForm({form: SuperForm})
class Super extends React.Component {
  render() {
    const {form} = this.props
    const {values, errors, touched} = form
    return (
      <div>
        {
          values.map((sub, ii) => (
            <Sub
              form={sub}
              prefix={ii}
            />
          ))
        }
      </div>
    )
  }
}