Gets attribute off HTML element or nearest parent

get-nearest-html-attribute.js

/**
 * Gets attribute off HTML element or nearest parent
 * @param {object} el - HTML element to retrieve attribute from
 * @param {string} attributeName - name of the attribute
 * @param {any} defaultValue - default value to return if no match found
 * @returns {any} attribute value or defaultValue
 */
function getNearestAttribute(el, attributeName, defaultValue) {

    // walk up the dom tree looking for data-action and data-trigger
    while (el && el !== document.documentElement) {

        var attributeValue = el.getAttribute(attributeName);

        if (attributeValue) {
            return attributeValue;
        }

        el = el.parentNode;
    }

    return defaultValue;
}