文章目录
概要
因为商品是经常被浏览的,所以数据库的访问量就问大大增加,造成负载过大影响性能,所以我们需要把商品缓存到redis当中,因为redis是存在内存中的,所以效率会比MySQL的快.
整体架构流程
技术细节
- 我们在缓存时需要保持数据的一致性
- 所以当管理端用户进行增删改操作的时候需要清理缓存,否则用户看到的商品则是缓存中的(未被修改的商品)
小结
java
@GetMapping("/list")
@ApiOperation("根据分类id查询菜品")
public Result<List<DishVO>> list(Long categoryId) {
//缓存菜品
String key = "dish_" + categoryId;
List<DishVO> list = (List<DishVO>) redisTemplate.opsForValue().get(key);
if (list != null && list.size() > 0) {
return Result.success(list);
}
Dish dish = new Dish();
dish.setCategoryId(categoryId);
dish.setStatus(StatusConstant.ENABLE);//查询起售中的菜品
list = dishService.listWithFlavor(dish);
//如果不存在则查数据库存入redis
redisTemplate.opsForValue().set(key,list);
return Result.success(list);
}
。
java
package com.sky.controller.admin;
import com.sky.dto.DishDTO;
import com.sky.dto.DishPageQueryDTO;
import com.sky.entity.Dish;
import com.sky.result.PageResult;
import com.sky.result.Result;
import com.sky.service.DishService;
import com.sky.vo.DishVO;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.annotations.Delete;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.bind.annotation.*;
import javax.websocket.server.PathParam;
import java.util.List;
import java.util.Set;
@RestController
@RequestMapping("admin/dish")
@Slf4j
@Api(tags = "菜品相关接口")
public class DishController {
@Autowired
private DishService dishService;
@Autowired
private RedisTemplate redisTemplate;
/**
* 新增菜品
* @param dishDTO
* @return
*/
@PostMapping
@ApiOperation("新增菜品")
public Result save(@RequestBody DishDTO dishDTO){
Long categoryId = dishDTO.getCategoryId();
String key = "dish_" + categoryId;
deleteCache(key);
dishService.saveWithFlavor(dishDTO);
return Result.success();
}
/**
* 菜品分页查询
* @param dishPageQueryDTO
* @return
*/
@GetMapping("/page")
@ApiOperation("菜品分页查询")
public Result<PageResult> page(DishPageQueryDTO dishPageQueryDTO){
log.info("菜品分页查询:{}", dishPageQueryDTO);
PageResult pageResult = dishService.pageQuery(dishPageQueryDTO);
return Result.success(pageResult);
}
/**
* 批量删除菜品
* @param ids
* @return
*/
@DeleteMapping
@ApiOperation("批量删除菜品")
public Result delete(@RequestParam List<Long> ids){
log.info("批量删除菜品:{}", ids);
deleteCache("dish_*");
dishService.deleteBatch(ids);
return Result.success();
}
/**
* 根据id查询菜品
* @param id
* @return
*/
@GetMapping("/{id}")
@ApiOperation("根据id查询菜品")
public Result<DishVO> getById(@PathVariable Long id){
log.info("根据id查询菜品");
DishVO dishVO = dishService.getByIdWithFlavor(id);
return Result.success(dishVO);
}
/**
* 修改菜品
* @param dishDTO
* @return
*/
@PutMapping
@ApiOperation("修改菜品")
public Result update(@RequestBody DishDTO dishDTO){
log.info("修改菜品:{}",dishDTO);
deleteCache("dish_*");
dishService.updateWithFlavor(dishDTO);
return Result.success();
}
@GetMapping("/list")
public Result<List<Dish>> list(@RequestParam Long categoryId){
log.info("根据分类id查询菜品:{}",categoryId);
List<Dish> list = dishService.list(categoryId);
return Result.success(list);
}
@PostMapping("/status/{status}")
@ApiOperation("菜品起售停售")
public Result<String> startOrStop(@PathVariable Integer status, Long id){
deleteCache("dish_*");
dishService.startOrStop(status,id);
return Result.success();
}
private void deleteCache(String pattern){
Set keys = redisTemplate.keys(pattern);
redisTemplate.delete(keys);
}
}