MobX Ajv Form

Easly manage Forms with MobX and automatic validation with AJV json-schema rules.

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Changelog & Documentation

See the Changelog or the Documentation for all the details.

Install

npm i --save mobx-ajv-form

Demo

http://www.webpackbin.com/EJE_QL1OW

Usage

import Form from 'mobx-ajv-form';

// define a json schema

const schema = {
  type: 'object',
  properties: {
    username: { type: 'string', minLength: 6, maxLength: 20 },
    email: { type: 'string', format: 'email', minLength: 5, maxLength: 20 },
    password: { type: 'string', minLength: 6, maxLength: 20 }
  }
};

// define fields

const fields = {
  username: {
    label: 'Username',
    value: 'SteveJobs'
  },
  email: {
    label: 'Email',
    value: '[email protected]'
  },
  password: {
    label: 'Password',
    value: 'thinkdifferent'
  }
};

// create the form

export default new Form({ fields, schema });

Pass the form to a react component:

import React from 'react';
import { observer } from 'mobx-react';

const FormComponent = ({ form, handleOnSubmit }) => (
  <form>
    <input
      type="text"
      name={form.fields.username.name}
      value={form.fields.username.value}
      placeholder={form.fields.username.label}
      onChange={form.syncValue}
    />
    <p>{form.fields.username.errorMessage}</p>

    ...

    <button
      type="submit"
      disabled={!form.valid}
      onClick={handleOnSubmit}
    >Register</button>

    <p>{form.genericErrorMessage}</p>
  </form>
);

export default observer(FormComponent);

Deal with events:

import form from './form';

export const handleOnSubmit = (e) => {
  e.preventDefault();

  if (!form.validate()) return;

  alert('Form is valid! Send the request here.');

  // get fields values
  console.log('Form Values', form.values());

  // clear the form
  form.clear();

  // or reset to the default initial values
  // form.reset();

  // or show a custom generic error
  form.invalidate('The user already exist.')

  // or update with new values
  // form.update({ username: 'Jonathan Ive' });
}

Use a custom validation function:

// define custom functions,
// they must return an array with: [boolean, string];

function shouldBeEqualTo($target) {
  const target = $target;
  return (field, fields) => {
    const current = field.label || field.name;
    const fieldsAreEquals = (fields[target].getValue() === field.getValue());
    return [fieldsAreEquals, `The ${current} should be equals to ${target}`];
  };
}

function isEmail(field) {
  const current = field.label || field.name;
  const isValid = (field.value.indexOf('@') > 0);
  return [isValid, `The ${current} should be an email address.`];
}

// pass them to the field's `validate` property
// as function or as an array of functions
// and set `related fields to be validated at the same time

const fields = {
  username: {
    label: 'Username',
    value: '[email protected]',
    validate: [isEmail, shouldBeEqualTo('email')],
    related: ['email'],
  },
  email: {
    label: 'Email',
    value: '[email protected]',
    validate: isEmail,
    related: ['username'],
  },
  ...
};