package new import "time" type Option func(opt *configs) type configs struct { //长连接监听端口 port int //长连接允许最大链接数 maxConnNum int64 //连接握手超时时间 handshakeTimeout time.Duration //允许消息最大长度 messageMaxMsgLength int } func WithPort(port int) Option { return func(opt *configs) { opt.port = port } } func WithMaxConnNum(num int64) Option { return func(opt *configs) { opt.maxConnNum = num } } func WithHandshakeTimeout(t time.Duration) Option { return func(opt *configs) { opt.handshakeTimeout = t } } func WithMessageMaxMsgLength(length int) Option { return func(opt *configs) { opt.messageMaxMsgLength = length } }