深入解析Golang中的Cache::remember方法实现

package main

import "fmt"

type Person interface {
    Say()
    Name()
}

type Parent struct {
}

func (s *Parent) Say() {
    fmt.Println("i am " + s.Name())
}

func (s *Parent) Name() string {
    return "parent"
}

type Child struct {
    Parent
}

func (s *Child) Name() string {
    return "child"
}

func main() {
    var c Child
    // 输出: i am parent
    c.Say()
}

import (
    "context"
    "encoding/json"
    "fmt"
    "github.com/gin-gonic/gin"
    "time"
)

func CacheGet(c context.Context, t interface{}, cacheKey string, callQuery func() error) error {
    // 尝试从 Redis 中获取数据
    dataBytes, err := redis.Get(c, cacheKey).Bytes()
    if err == nil {
        if err := json.Unmarshal(dataBytes, t); err == nil {
            return nil
        }
    }

    // 如果缓存中没有数据，则执行数据库查询
    if err := callQuery(); err != nil {
        return err
    }

    // 将查询结果存入缓存
    dataBytes, err = json.Marshal(t)
    if err == nil {
        redis.Set(c, cacheKey, dataBytes, time.Minute*30)
    }
    return nil
}

func handle(c *gin.Context) {
    var model models.User
    err := utils.CacheGet(
        c.Request.Context(),
        &model,
        fmt.Sprintf("cache_xxx:%s", c.Param("id")),
        func() error {
            return db.First(&model)
        },
    )
}