registry: implement redis backend (#2179)

internal/registry/redis/option.go

@@ -0,0 +1,48 @@
+package redis
+
+import (
+	"crypto/tls"
+	"time"
+)
+
+const defaultTTL = time.Second * 30
+
+type config struct {
+	tls    *tls.Config
+	ttl    time.Duration
+	getNow func() time.Time
+}
+
+// An Option modifies the config..
+type Option func(*config)
+
+// WithGetNow sets the time.Now function in the config.
+func WithGetNow(getNow func() time.Time) Option {
+	return func(cfg *config) {
+		cfg.getNow = getNow
+	}
+}
+
+// WithTLSConfig sets the tls.Config in the config.
+func WithTLSConfig(tlsConfig *tls.Config) Option {
+	return func(cfg *config) {
+		cfg.tls = tlsConfig
+	}
+}
+
+// WithTTL sets the ttl in the config.
+func WithTTL(ttl time.Duration) Option {
+	return func(cfg *config) {
+		cfg.ttl = ttl
+	}
+}
+
+func getConfig(options ...Option) *config {
+	cfg := new(config)
+	WithGetNow(time.Now)(cfg)
+	WithTTL(defaultTTL)(cfg)
+	for _, o := range options {
+		o(cfg)
+	}
+	return cfg
+}