Magnacarter/translate.js

## translate.js
/**
 * Track pageviews when the page is translated directly from translate.google.com or bing.com/translator
 * and return an individual query parameter.
 *
 * @param  string name
 * @return string results
 */
const getUrlParameter = ( name ) => {
	name = name.replace( /[\[]/, '\\[').replace(/[\]]/, '\\]' );

	let regex   = new RegExp( '[\\?&]' + name + '=([^&#]*)' ),
	    results = regex.exec( location.search );

	if ( results !== null ) {
		results = decodeURIComponent( results[1].replace( /\+/g, ' ' ) );
	} else {
		return;
	}

	return results;
};

/**
 * Callback for mutation callback. Pushes key/value
 * pairs to the client's dataLayer object for each
 * mutation.
 *
 * @param mutation
 * @return void
 */
const mutationForeachCallback = ( mutation ) => {
	let oldElementClass     = mutation.oldValue,
	    currentElementClass = mutation.target.className;

	if ( oldElementClass.indexOf('translated-') === -1 && currentElementClass.indexOf('translated-') > -1) {
		console.log( mutation );
		window.dataLayer.push({
			'event': 'pageTranslated',
			'translationLanguage': mutation.target.lang || document.getElementsByTagName('html')[0].getAttribute('xml:lang'),
			'translationService': 'On-Page Google Translate',
		});
	}
}

/**
 * Callback function for MutationObserver object.
 *
 * @param  mutations
 * @return void
 */
const mutationObserverCallback = ( mutations ) => {
	mutations.forEach( mutationForeachCallback( mutation ) );
}

// Observe DOM mutations whether the <html> node was changed by Google Translate.
if ( window.MutationObserver ) {
	let htmlNode         = document.querySelector( 'html' ),
	    mutationObserver = new MutationObserver( mutationObserverCallback( mutations ) );

	mutationObserver.observe(htmlNode, {
		attributes: true,
		attributeOldValue: true,
		attributeFilter: ['class'],
	});
}

// Check if the page is being translated directly from translate.google.com (viewed within the iframe)
if ( window.location.href.indexOf( 'translate.googleusercontent.com' ) > -1 ) {
	window.dataLayer.push({
		'event': 'pageTranslated',
		'translationLanguage': getUrlParameter( 'tl' ),
		'translationService': 'Google Translate Website',
	});
}

// Check if the page is being translated directly from bing.com/translator (viewed within the iframe)
if ( window.location.href.indexOf( 'translatoruser-int.com' ) > -1 ) {
	window.dataLayer.push({
		'event': 'pageTranslated',
		'translationLanguage': getUrlParameter( 'to' ),
		'translationService': 'Bing Translator Website'
	});
}
	/**
	* Track pageviews when the page is translated directly from translate.google.com or bing.com/translator
	* and return an individual query parameter.
	*
	* @param string name
	* @return string results
	*/
	const getUrlParameter = ( name ) => {
	name = name.replace( /[\[]/, '\\[').replace(/[\]]/, '\\]' );

	let regex = new RegExp( '[\\?&]' + name + '=([^&#]*)' ),
	results = regex.exec( location.search );

	if ( results !== null ) {
	results = decodeURIComponent( results[1].replace( /\+/g, ' ' ) );
	} else {
	return;
	}

	return results;
	};

	/**
	* Callback for mutation callback. Pushes key/value
	* pairs to the client's dataLayer object for each
	* mutation.
	*
	* @param mutation
	* @return void
	*/
	const mutationForeachCallback = ( mutation ) => {
	let oldElementClass = mutation.oldValue,
	currentElementClass = mutation.target.className;

	if ( oldElementClass.indexOf('translated-') === -1 && currentElementClass.indexOf('translated-') > -1) {
	console.log( mutation );
	window.dataLayer.push({
	'event': 'pageTranslated',
	'translationLanguage': mutation.target.lang \|\| document.getElementsByTagName('html')[0].getAttribute('xml:lang'),
	'translationService': 'On-Page Google Translate',
	});
	}
	}

	/**
	* Callback function for MutationObserver object.
	*
	* @param mutations
	* @return void
	*/
	const mutationObserverCallback = ( mutations ) => {
	mutations.forEach( mutationForeachCallback( mutation ) );
	}

	// Observe DOM mutations whether the <html> node was changed by Google Translate.
	if ( window.MutationObserver ) {
	let htmlNode = document.querySelector( 'html' ),
	mutationObserver = new MutationObserver( mutationObserverCallback( mutations ) );

	mutationObserver.observe(htmlNode, {
	attributes: true,
	attributeOldValue: true,
	attributeFilter: ['class'],
	});
	}

	// Check if the page is being translated directly from translate.google.com (viewed within the iframe)
	if ( window.location.href.indexOf( 'translate.googleusercontent.com' ) > -1 ) {
	window.dataLayer.push({
	'event': 'pageTranslated',
	'translationLanguage': getUrlParameter( 'tl' ),
	'translationService': 'Google Translate Website',
	});
	}

	// Check if the page is being translated directly from bing.com/translator (viewed within the iframe)
	if ( window.location.href.indexOf( 'translatoruser-int.com' ) > -1 ) {
	window.dataLayer.push({
	'event': 'pageTranslated',
	'translationLanguage': getUrlParameter( 'to' ),
	'translationService': 'Bing Translator Website'
	});
	}