@financial-times/o-tracking/src/javascript/core/transports/image.js

Provides tracking for a product. Tracking requests are sent to the Spoor API.

import {encode} from '../../utils.js';

/**
 * Image based transport mechanism
 *
 * @returns {object} - Object with three properties: name, send and complete
 */
function image () {
	const image = new Image(1,1);

	return {
		name: 'image',
		send: function (url, data) {
			url = url.replace('https://spoor-api.ft.com/ingest', 'https://spoor-api.ft.com/px.gif');
			image.src = url + (url.indexOf('?') > -1 ? '&' : '?') + 'data=' + encode(data);
		},
		complete: function (callback) {
			if (image.addEventListener) {
				image.addEventListener('error', callback);
				image.addEventListener('load', () => callback());
			} else { // it's IE!
				image.attachEvent('onerror', callback);
				image.attachEvent('onload', () => callback());
			}
		}
	};
}

export { image };