bundle.go

func NewClusterFromBundle(bundlePath string) (*gocql.ClusterConfig, error) {
	reader, err := zip.OpenReader(bundlePath)
	if err != nil {
		return nil, err
	}

	defer reader.Close()

	contents := make(map[string][]byte)

	for _, file := range reader.File {
		switch file.Name {
		case "config.json", "cert", "key", "ca.crt":
			bytes, err := loadBytes(file)
			if err != nil {
				return nil, err
			}
			contents[file.Name] = bytes
		}
	}

	config := struct {
		Host     string `json:"host"`
		Port     int    `json:"cql_port"`
		Keyspace string `json:"keyspace"`
	}{}

	err = json.Unmarshal(contents["config.json"], &config)
	if err != nil {
		return nil, err
	}

	cert, err := tls.X509KeyPair(contents["cert"], contents["key"])
	if err != nil {
		return nil, err
	}
	caCerts := x509.NewCertPool()
	if ok := caCerts.AppendCertsFromPEM(contents["ca.crt"]); !ok {
		return nil, fmt.Errorf("unable to load CA certificate")
	}
	tlsConfig := tls.Config{
		Certificates: []tls.Certificate{cert},
		RootCAs:      caCerts,
	}

	hosts, _ := lookupHost(config.Host, strconv.Itoa(config.Port))

	cluster := gocql.NewCluster(hosts...)
	cluster.HostFilter = ContactPointHostFilter(hosts)
	cluster.Port = config.Port
	cluster.Keyspace = config.Keyspace
	cluster.SslOpts = &gocql.SslOptions{
		Config: &tlsConfig,
	}

	return cluster, nil
}