GORM with Memorystore

GORM_caching_with_memorystore.go

package main

import (
	"context"
	"fmt"
	"time"
	"io"

	"github.com/go-gorm/caches/v4"
	"github.com/redis/go-redis/v9"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"crypto/md5"
)

type UserRoleModel struct {
	gorm.Model
	Name string `gorm:"unique"`
}

type UserModel struct {
	gorm.Model
	Name   string
	RoleId uint
	Role   *UserRoleModel `gorm:"foreignKey:role_id;references:id"`
}

type redisCacher struct {
	rdb *redis.Client
}

func (c *redisCacher) Get(ctx context.Context, key string, q *caches.Query[any]) (*caches.Query[any], error) {
	h := md5.New()
	io.WriteString(h, key)	
	res, err := c.rdb.Get(
		ctx,
		fmt.Sprintf("%s%s", caches.IdentifierPrefix, string(h.Sum(nil)))).Result()
	if err == redis.Nil {
		return nil, nil
	}

	if err != nil {
		return nil, err
	}

	if err := q.Unmarshal([]byte(res)); err != nil {
		return nil, err
	}

	return q, nil
}

func (c *redisCacher) Store(ctx context.Context, key string, val *caches.Query[any]) error {
	res, err := val.Marshal()
	if err != nil {
		return err
	}
	h := md5.New()
	io.WriteString(h, key)	

	c.rdb.Set(
		ctx,
		fmt.Sprintf("%s%s", caches.IdentifierPrefix, string(h.Sum(nil))),
		res,
		300*time.Second,
	) // Set proper cache time
	return nil
}

func (c *redisCacher) Invalidate(ctx context.Context) error {
	var (
		cursor uint64
		keys   []string
	)
	for {
		var (
			k   []string
			err error
		)
		k, cursor, err = c.rdb.Scan(ctx, cursor, fmt.Sprintf("%s*", caches.IdentifierPrefix), 0).Result()
		if err != nil {
			return err
		}
		keys = append(keys, k...)
		if cursor == 0 {
			break
		}
	}

	if len(keys) > 0 {
		if _, err := c.rdb.Del(ctx, keys...).Result(); err != nil {
			return err
		}
	}
	return nil
}

func main() {
	db, _ := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
		AllowGlobalUpdate: true,
	})

	cachesPlugin := &caches.Caches{Conf: &caches.Config{
		Cacher: &redisCacher{
			rdb: redis.NewClient(&redis.Options{
				Addr:     "localhost:6379",
				Password: "",
				DB:       0,
			}),
		},
	}}

	_ = db.Use(cachesPlugin)

	_ = db.AutoMigrate(&UserRoleModel{})
	_ = db.AutoMigrate(&UserModel{})

	db.Delete(&UserRoleModel{})
	db.Delete(&UserModel{})

	adminRole := &UserRoleModel{
		Name: "Admin",
	}
	db.Save(adminRole)

	guestRole := &UserRoleModel{
		Name: "Guest",
	}
	db.Save(guestRole)

	db.Save(&UserModel{
		Name: "ktsivkov",
		Role: adminRole,
	})

	db.Save(&UserModel{
		Name: "anonymous",
		Role: guestRole,
	})

	q1User := &UserModel{}
	db.WithContext(context.Background()).Find(q1User, "Name = ?", "ktsivkov")
	q2User := &UserModel{}
	db.WithContext(context.Background()).Find(q2User, "Name = ?", "ktsivkov")

	fmt.Println(fmt.Sprintf("%+v", q1User))
	fmt.Println(fmt.Sprintf("%+v", q2User))
}