public void UrlCheckTest()
        {
            /*
             * The protocol is equal to https (case insensitive).
             * The hostname is equal to s3.amazonaws.com (case insensitive).
             * The path starts with /echo.api/ (case sensitive).
             * If a port is defined in the URL, the port is equal to 443.
             */

            string[] correctUrls =
            {
                "https://s3.amazonaws.com/echo.api/echo-api-cert.pem",
                "https://s3.amazonaws.com:443/echo.api/echo-api-cert.pem",
                "https://s3.amazonaws.com/echo.api/../echo.api/echo-api-cert.pem"
            };


            var validator = new DotNetCertValidator()
            {
                Header = new RequestHeader()
            };

            foreach (var item in correctUrls)
            {
                validator.Header.CertChainUrl = item;
                Assert.IsTrue(validator.VerifyCertificateUrl());
            }

            string[] invalidUrls =
            {
                null,
                string.Empty,
                "http://s3.amazonaws.com/echo.api/echo-api-cert.pem",      // invalid protocol
                "https://notamazon.com/echo.api/echo-api-cert.pem",        // invalid hostname
                "https://s3.amazonaws.com/EcHo.aPi/echo-api-cert.pem",     //invalid path
                "https://s3.amazonaws.com/invalid.path/echo-api-cert.pem", //invalid path
                "https://s3.amazonaws.com:563/echo.api/echo-api-cert.pem", //invalid port
            };

            foreach (var item in invalidUrls)
            {
                validator.Header.CertChainUrl = item;
                Assert.IsFalse(validator.VerifyCertificateUrl());
            }
        }