improve gredis instance initialization for gins

.example/database/gredis/migration/migration.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/gogf/gf/util/gconv"
+
+	"github.com/gogf/gf/os/gcmd"
+
+	"github.com/gogf/gf/container/garray"
+	"github.com/gogf/gf/database/gredis"
+	"github.com/gogf/gf/frame/g"
+)
+
+func main() {
+	batchNumber := 1000
+	redis1Config, err := gredis.ConfigFromStr("im-redis-slave:6379,9")
+	if err != nil {
+		panic(err)
+	}
+	redis2Config, err := gredis.ConfigFromStr("r-bp1f0a5d4efd8744.redis.rds.aliyuncs.com:6379,9")
+	if err != nil {
+		panic(err)
+	}
+	gredis.SetConfig(redis1Config)
+
+	v, err := g.Redis().DoVar("keys", "*")
+	if err != nil {
+		panic(err)
+	}
+	array := garray.NewStrArrayFrom(v.Strings())
+	for {
+		slice := array.PopLefts(batchNumber)
+		if len(slice) > 0 {
+			// `migrate %s %d "" 0 2000 copy replace auth %s keys %s`,
+			params := g.Slice{
+				redis2Config.Host,
+				redis2Config.Port,
+				"",
+				redis2Config.Db,
+				2000,
+				"copy",
+				"replace",
+				"keys",
+			}
+			params = append(params, gconv.Interfaces(slice)...)
+			fmt.Println(params)
+			if gcmd.GetOpt("dryrun") == "0" {
+				if v, err := g.Redis().DoVar("migrate", params...); err != nil {
+					panic(err)
+				} else {
+					fmt.Println(v.String())
+				}
+			}
+		} else {
+			break
+		}
+	}
+	fmt.Println("done")
+}