MooTools based validation system that uses schema-files written in JSON to define validation rules and flows. Requires the use of the JS-Form repo's SmartForm class.
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JS-JSON-Validation is a front-end validation framework. It validates a form by evaluating a series of rules that are defined through an associated JSON file (known as a schema).

Designed to work seamlessly (but requiring implementation attention) with the PHP-JSON-Validation project.

In-depth Examples

Which this page does contain an example, including the implementation of a SmartForm instance, I've prepared in-depth examples which can be seen here:

The final example available through this page presents a realistic example; a comment form which prompts a user for their name, email, website, comments and whether they want to subscribe to email updates for this page.

It highlights sub-rules, funnels and blocking rules, along with a variety of validation rule types and error messaging.

Public Methods

A SchemaValidator instance has only two publicly accessible methods:

  • validate

    Requires success and failure functions to be passed in, which respectively get executed after the form rules have been executed.

  • getFailedRules

    Returns an array of all the rules which have failed. The result of this depends on whether a blocking rule failed in a rule-stack (see below for more information on blocking rules).

Validation Pieces

In order for a form to be successfully validated, it's schema must have all it's rules successfully validated (with the exception of rules which are marked as a funnel). This is a recursive requirement for all rules which themselves have sub-rules as well.

There are 5 properties that are useful when creating rules for a schema. They are:

  • validator (required)
  • params (optional)
  • blocking (optional)
  • rules (optional)
  • funnel (optional)

To save on redundancy, and keep documentation on them normalized, please check out the Validation Pieces section on the PHP-JSON-Validation project.

There is one other property, the error property, which while not used by the validation engine, is suggested in order to develop a more useful error validation flow.

SmartForm Example

The following illustrates the validation of a form through the usage of SmartForm instance. A SmartForm instance is created whereby the presubmit property passed in contains the validation flow.

This flow overrides the default where the presubmit callback method is immediately triggered. Alternatively, it creates a SchemaValidator instance, passing in a schema array and inputs object.

Following this, the validator fires off the validate method which accepts two functions. One which is executed upon successful validation (which simply executes the default callback parameter), and one which is executed upon failure (which in this case retrieves the failed rules, alerts the message from the schema, focuses on the input, and re-enables the form to be submittable again through the SmartForm instance).

var smartform = (new SmartForm(
        postsubmit: function() {
            alert('Form has been submitted.');
        presubmit: function(callback) {

            // validation object
            var inputs = this.getInputs(),
                validator = (new SchemaValidator(
                    schema, inputs

            // validate
                function() {
                function() {
                    var failed = this.getFailedRules()[0],
                        input = $('form-id').getElement('*[name=' + failed.error.input + ']');