9. cache optimization

Cache optimization

1、 Environment building

1.1、 Import maven

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

1.2、 To configure redis

my redis Put it directly in windows On , therefore host For local address . See this blog for installation methods ：https://www.redis.com.cn/redis-installation.html

1.3、redis Configuration class

stay config Create under directory RedisConfig class ,

It is not recommended here to value Also set to StringRedisSerializer, If I set it to StringRedisSerializer, Backward redis A conversion exception occurs when a collection is stored in .

@Configuration
public class RedisConfig extends CachingConfigurerSupport {
    

    @Bean
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
    
        RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
        // default Key The serializer is ：JdkSerializationRedisSerializer
        redisTemplate.setKeySerializer(new StringRedisSerializer()); // key serialize 
        redisTemplate.setConnectionFactory(connectionFactory);
        return redisTemplate;
    }

}

1.4、 push

Submit and push to github, Signature ：redis Environment configuration . Note that the branch is v1.0

2、 Cache SMS verification code

2.1、 Realize the idea

1. On the server UserController In the injection RedisTemplate object , Used to operate Redis
2. On the server UserController Of sendMsg In the method , Cache the randomly generated verification code to Redis in , And set the validity period as 5 minute
3. On the server UserController Of login In the method , from Redis Get the cached verification code , If the login is successful, delete Redis Verification code in

2.2、 modify UserController

2.2.1、 modify sendMsg Method

2.2.2、 modify login Method

2.3、 test

To install a redis Visual interface for testing , I'm using Another Redis Desktop Manager

2.4、 Push code

Submit and push code , Signature ： Cache SMS verification code .

3、 Cache dishes

3.1、 Realize the idea

1. reform DishController Of list Method , First from Redis Get dish data from , Direct return if any , No need to query the database ; If not, query the database , And put the queried dish data into Redis.
2. reform DishController Of save and update Method , Add the logic to clean up the cache

3.2、 modify DishController

3.2.1、 modify list Method

/** *  Query the corresponding dish data according to the conditions  * * @param dish * @return */
@GetMapping("/list")
public R<List<DishDto>> list(Dish dish) {
    
    List<DishDto> dishDtoList = null;

    String key = "dish_" + dish.getCategoryId() + "_" + dish.getStatus();

    //  First from redis get data 
    dishDtoList = (List<DishDto>) redisTemplate.opsForValue().get(key);

    if (dishDtoList != null) {
    
        //  If redis If there is data in, it will be returned directly 
        return R.success(dishDtoList);
    }

    //  Construct query conditions 
    LambdaQueryWrapper<Dish> queryWrapper = new LambdaQueryWrapper<>();
    queryWrapper.eq(dish.getCategoryId() != null, Dish::getCategoryId, dish.getCategoryId());
    //  The query status is 1 The dishes 
    queryWrapper.eq(Dish::getStatus, 1);

    //  Add sorting criteria 
    queryWrapper.orderByAsc(Dish::getSort).orderByDesc(Dish::getUpdateTime);

    List<Dish> list = dishService.list(queryWrapper);

    dishDtoList = list.stream().map(item -> {
    
        DishDto dishDto = new DishDto();
        //  Copy properties 
        BeanUtils.copyProperties(item, dishDto);

        //  Set up DishDto Category name attribute 
        Long categoryId = item.getCategoryId();
        Category category = categoryService.getById(categoryId);
        if (category != null) {
    
            String categoryName = category.getName();
            dishDto.setCategoryName(categoryName);
        }

        //  Set the dish taste 
        Long dishId = item.getId();
        LambdaQueryWrapper<DishFlavor> dishFlavorLambdaQueryWrapper = new LambdaQueryWrapper<>();
        dishFlavorLambdaQueryWrapper.eq(DishFlavor::getDishId, dishId);
        // SQL: select * from dish_flavor where dish_id = ?
        List<DishFlavor> dishFlavorList = dishFlavorService.list(dishFlavorLambdaQueryWrapper);
        dishDto.setFlavors(dishFlavorList);

        return dishDto;
    }).collect(Collectors.toList());

    //  Store data redis
    redisTemplate.opsForValue().set(key, dishDtoList, 60, TimeUnit.MINUTES);

    return R.success(dishDtoList);
}

3.2.2、 modify update Method

/** *  Modify the dishes  * @param dishDto * @return */
@PutMapping
public R<String> update(@RequestBody DishDto dishDto) {
    
    log.info(dishDto.toString());

    dishService.updateWithFlavor(dishDto);

    //  Clear the cache data of all dishes 
    // Set keys = redisTemplate.keys("dish_*");
    // redisTemplate.delete(keys);
    
    //  Clear the cache data of dishes under a category 
    String key = "dish_" + dishDto.getCategoryId() + "_1";
    redisTemplate.delete(key);

    return R.success(" Dishes modified successfully ");
}

3.2.3、 modify save Method

/** *  New dishes  * @param dishDto * @return */
@PostMapping
public R<String> save(@RequestBody DishDto dishDto) {
    
    log.info(dishDto.toString());
    dishService.saveWithFlavor(dishDto);

    //  Clear the cache data of all dishes 
    // Set keys = redisTemplate.keys("dish_*");
    // redisTemplate.delete(keys);

    //  Clear the cache data of dishes under a category 
    String key = "dish_" + dishDto.getCategoryId() + "_1";
    redisTemplate.delete(key);
    
    return R.success(" Added dishes successfully ");
}

3.2.4、 modify delete Method

/** *  Logical deletion  * @param ids * @return */
@DeleteMapping
@Transactional
public R<String> delete(Long[] ids) {
    
    log.info(" Batch deleted id：{}", Arrays.toString(ids));
    //  First, delete the taste information corresponding to the dishes 
    dishFlavorService.removeByDishIds(Arrays.asList(ids));
    //  Delete the dishes logically 
    dishService.removeByIds(Arrays.asList(ids));

    //  Clear the cache data of all dishes 
    // Set keys = redisTemplate.keys("dish_*");
    // redisTemplate.delete(keys);

    //  according to dishId Set query categoryId aggregate 
    List<Dish> dishes = dishService.listByIds(Arrays.asList(ids)); //  Query all id stay ids Inside dish Record 
    Set<Long> categoryIds = dishes.stream().map(Dish::getCategoryId).collect(Collectors.toSet());//  Take out the fields category_id aggregate ,set Collections prevent duplication 

    //  Clear all id stay categoryIds Cache in 
    categoryIds.forEach(item -> {
    
        String key = "dish_" + item + "_1";
        redisTemplate.delete(key);
    });

    return R.success(" Delete dishes successfully ");
}

3.2.5、 Test the cache effect

3.2.6、 Push code

Submit and push code , Signature ： Cache dishes . Branch ：v1.0

4、 Merge code

take v1.0 The branch code is merged into the main branch

1. Switch back to main branch
2. Click again v1.0 Merge button for branches
3. After merging, switch back to v1.0 The branch continues to develop

5、SpringCache Cache package data

5.1、 Realize the idea

1. Import Spring Cache and Redis relevant maven coordinate
2. stay application.yml Configure the expiration time of cached data in
3. Add on startup class @EnableCaching annotation , Enable the cache annotation function
4. stay SetmealController Of list Add... To the method @Cacheable annotation
5. stay SetmealController Of save and delete Add... To the method CacheEvict annotation

5.2、 Import maven

We've imported redis Related dependence of , Now just import spring cache：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-cache</artifactId>
</dependency>

5.3、 Enable caching

Mark... On the startup class @EnableCaching annotation

5.4、 Return type R Implement serialization

public class R<T> implements Serializable

5.5、 Cache package information

1、 modify SetmealController Inside list Method

/** *  According to the classification id And status query package  * @param setmeal * @return */
@GetMapping("/list")
@Cacheable(value = "setmealCache", key = "#setmeal.categoryId + '_' + #setmeal.status")
public R<List<Setmeal>> list(Setmeal setmeal) {
    
    LambdaQueryWrapper<Setmeal> queryWrapper = new LambdaQueryWrapper<>();
    queryWrapper.eq(setmeal.getCategoryId() != null, Setmeal::getCategoryId, setmeal.getCategoryId());
    queryWrapper.eq(setmeal.getStatus() != null, Setmeal::getStatus, setmeal.getStatus());
    queryWrapper.orderByDesc(Setmeal::getUpdateTime);

    List<Setmeal> list = setmealService.list(queryWrapper);

    return R.success(list);
}

2、 to SetmealController Under the delete、save、update Methods are marked with the following comments

@CacheEvict(value = "setmealCache", allEntries = true)

5.6、 Test cache

Click package query after logging in the mobile interface , See the effect

5.7、 Push code & Merge

Submit and push code , Signature ：spring cache Cache package data . Branch ：v1.0

Merge steps ：

1. Switch to master Branch
2. Click on v1.0 Click the merge button of the branch to merge