frint-data-validation

Reactive data modelling package for Frint

• Guide
  • Installation
  • Usage
• API
  • validate
  • validate$

Guide

Installation

With npm:

$ npm install --save frint-data frint-data-validation

Via unpkg CDN:

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/5.5.0/Rx.min.js"></script>

<script src="https://unpkg.com/frint-data@latest/dist/frint-data.min.js"></script>
<script src="https://unpkg.com/frint-data@latest/dist/frint-data-validation.min.js"></script>

<script>
  // available as `window.FrintDataValidation`
</script>

Usage

Validation rules can be set in two ways using frint-data-validation.

1. Defining rules in Model classes statically
2. Passing rules when calling the validate() function

Defining rules statically

Imagine we have a Post model with this schema:

import { Types, createModel } from 'frint-data';

const Post = createModel({
  schema: {
    title: Types.string,
  },
});

We can now optionally add our validation rules as follows:

Post.validationRules = [
  {
    name: 'titleIsNotEmpty', // this can come handy later for grouping errors
    message: 'Title must not be empty',
    rule: function (model) {
      // `model` is your Post model's instance
      if (post.title.length === 0) {
        // we will fail this validation check
        return false;
      }

      // everything is fine
      return true;
    }
  }
];

Validating the model

To get the output of validation errors:

import { validate } from 'frint-data-validation';

const post = new Post({ title: '' });
const validationErrors = validate(post);

Since our title is empty here, the validationErrors will return this array:

console.log(validationErrors);
// [
//   {
//     name: 'titleIsNotEmpty',
//     message: 'Title must not be empty'
//   }
// ]

If there were no errors, validationErrors would be an empty array.

Passing validation rules manually

You can also choose not to define the validation rules statically, and pass them when calling validate() function:

import { validate } from 'frint-data-validation';

const post = new Post({ title: '' });
const validationErrors = validate(post, {
  rules: [
    {
      name: 'titleIsNotEmpty',
      message: 'Title must not be empty',
      rule: model => model.title.length > 0,
    },
  ],
});

Observing validation errors

If you want to keep observing the model for new errors as it keeps changing:

import { validate$ } from 'frint-data-validation';

const validationErrors$ = validate$(post);

Now the validationErrors$ observable can be subscribed, and it will emit an array with this structure:

[
  {
    name: string,
    message: string,
  }
]

API

validate

validate(model, options)

Arguments

1. model (Model): Model instance from frint-data
2. options (Object)
3. options.rules (Array): Validation rules

Returns

Array of validation errors.

validate$

validate$(model, options)

Reactive version of validate function.

Returns

Observable of validation errors.