golang框架中如何集成缓存与数据库操作

import "github.com/go-redis/redis"

func main() {
    client := redis.NewClient(&redis.Options{
        Addr: "localhost:6379",
    })

    client.Set("key", "value", 0)
    value, err := client.Get("key").Result()
    if err != nil {
        panic(err)
    }
    fmt.Println("Retrieved value from cache:", value)
}

import "database/sql"

func main() {
    db, err := sql.Open("mysql", "user:password@tcp(localhost:3306)/database")
    if err != nil {
        panic(err)
    }
    defer db.Close()

    rows, err := db.Query("SELECT * FROM table")
    if err != nil {
        panic(err)
    }
    defer rows.Close()
    for rows.Next() {
        var id int
        var name string
        err := rows.Scan(&id, &name)
        if err != nil {
            panic(err)
        }
        fmt.Println(id, name)
    }
}

// 定义缓存客户端
var cache *redis.Client

// 数据库查询
func getFromDB(key string) string {
    dbConn, err := sql.Open("mysql", "user:password@tcp(localhost:3306)/database")
    if err != nil {
        panic(err)
    }
    defer dbConn.Close()

    row := dbConn.QueryRow("SELECT value FROM cache WHERE key = ?", key)
    var value string
    err = row.Scan(&value)
    if err != nil {
        panic(err)
    }
    return value
}

// 缓存获取
func getFromCache(key string) (string, error) {
    value, err := cache.Get(key).Result()
    if err == redis.Nil {
        return "", nil
    } else if err != nil {
        return "", err
    }
    return value, nil
}

// 处理函数
func handler(w http.ResponseWriter, r *http.Request) {
    key := r.URL.Query().Get("key")
    value, err := getFromCache(key)
    if err != nil {
        http.Error(w, "Error getting from cache", http.StatusInternalServerError)
        return
    }
    if value != "" {
        // 从缓存返回结果
        w.Write([]byte(value))
        return
    }

    // 从数据库获取结果并更新缓存
    value = getFromDB(key)
    cache.Set(key, value, 0)
    w.Write([]byte(value))
}