使用Node.js中的cassandra-driver通过SSL连接到Cassandra Apache

var tls = require('tls');
var fs = require('fs');
var options = {
	key : fs.readFileSync('client-key.pem'),cert : fs.readFileSync('client-cert.pem'),ca : [fs.readFileSync('server-cert.pem')]
};
var client = new Cassandra.Client({
		contactPoints : ['127.0.0.1'],authprovider : new Cassandra.auth.Plaintextauthprovider('Cassandra','Cassandra'),sslOptions : tls.connect(options)
	});

我做错了什么？
请帮忙！