package postgres import ( "time" ) const defaultExpiry = time.Hour * 24 type config struct { expiry time.Duration } // Option customizes a Backend. type Option func(*config) // WithExpiry sets the expiry for changes. func WithExpiry(expiry time.Duration) Option { return func(cfg *config) { cfg.expiry = expiry } } func getConfig(options ...Option) *config { cfg := new(config) WithExpiry(defaultExpiry)(cfg) for _, o := range options { o(cfg) } return cfg }