constructor(url, dataPath, verify) {
        this.checkURL = new RegExp('^(https?:\\/\\/)?' // protocol
            + '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.?)+[a-z]{2,}|' // domain name
            + '((\\d{1,3}\\.){3}\\d{1,3}))' // OR ip (v4) address
            + '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*' // port and path