<form class="form" action="#" id="custom-form" method="post">
    <fieldset class="fieldset">
    <div class="field required">
            <label class="label" for="custom-field"><span>Attribute Rule</span></label>
            <div class="control">
                <input name="custom-field" id="custom-field" title="Attribute Rule" value="ipv4" ipv4="true" class="input-text" type="text" />
            </div>
        </div>
    </fieldset>
</form>
<script type="text/x-magento-init">
    {
        "*": {
            "Magento_Customer/js/block-submit-on-send": {
                "formId": "custom-form"
            }
        }
    }
</script>

rules: function( command, argument ) {
...
              data = $.validator.normalizeRules(
                $.extend(
                    {},
                    $.validator.metadataRules(element),
                    $.validator.classRules( element ),
                    $.validator.attributeRules( element ),
                    $.validator.dataRules( element ),
                    $.validator.staticRules( element )
                ), element );

// debug the value
              if (!!$.validator.attributeRules(element) && Object.keys($.validator.attributeRules(element)).length > 0) {
                console.log($.validator.attributeRules(element));
              }
...