allow redis persistence config could be created with an existing redis client

pkg/service/persistence.go

@@ -1,6 +1,10 @@
 package service
 
-import "time"
+import (
+	"time"
+
+	"github.com/go-redis/redis/v8"
+)
 
 type PersistenceService interface {
 	NewStore(id string, subIDs ...string) Store
@@ -22,6 +26,10 @@ type RedisPersistenceConfig struct {
 	Password  string `yaml:"password,omitempty" json:"password,omitempty" env:"REDIS_PASSWORD"`
 	DB        int    `yaml:"db" json:"db" env:"REDIS_DB"`
 	Namespace string `yaml:"namespace" json:"namespace" env:"REDIS_NAMESPACE"`
+
+	// Redis is the redis client field
+	// this field is optional, only used when you want to set the redis client instance in the runtime
+	Redis *redis.Client
 }
 
 type JsonPersistenceConfig struct {

pkg/service/persistence_redis.go

@@ -22,13 +22,18 @@ type RedisPersistenceService struct {
 }
 
 func NewRedisPersistenceService(config *RedisPersistenceConfig) *RedisPersistenceService {
-	client := redis.NewClient(&redis.Options{
+	var client *redis.Client
+	if config.Redis != nil {
+		client = config.Redis
+	} else {
+		client = redis.NewClient(&redis.Options{
 			Addr: net.JoinHostPort(config.Host, config.Port),
 			// Username:           "", // username is only for redis 6.0
 			// pragma: allowlist nextline secret
 			Password: config.Password, // no password set
 			DB:       config.DB,       // use default DB
 		})
+	}
 
 	return &RedisPersistenceService{
 		redis:  client,