用户查询

# 用户信息查询

根据用户名查询用户信息：

@GetMapping("/api/shortlink/v1/user/{username}")
public Result<UserRespDTO> getUserByUsername(@PathVariable("username") String username) {
    return Results.success(userService.getUserByUsername(username));
}

1
2
3
4

@Override
public UserRespDTO getUserByUsername(String username) {
    LambdaQueryWrapper<UserDO> queryWrapper = Wrappers.lambdaQuery(UserDO.class)
            .eq(UserDO::getUsername, username);
    UserDO userDO = baseMapper.selectOne(queryWrapper);
    if(userDO == null){
        throw new ClientException(UserErrorCodeEnum.USER_NULL);
    }
    UserRespDTO result = new UserRespDTO();
    BeanUtils.copyProperties(userDO,result);
    return result;
}

1
2
3
4
5
6
7
8
9
10
11
12

根据用户名查询未脱敏用户信息：

只需要重新构建一个不加序列化器的RespDTO，其它逻辑一样；

# 判断用户存在

布隆过滤器

引入依赖：

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

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

1
2
3
4
5
6
7
8
9

配置文件配置Redis；

配置类：

@Configuration
public class RBloomFilterConfiguration {
    /**
     * 防止用户注册查询数据库的布隆过滤器
     */
    @Bean
    public RBloomFilter<String> userRegisterCachePenetrationBloomFilter(RedissonClient redissonClient) {
        RBloomFilter<String> cachePenetrationBloomFilter = redissonClient.getBloomFilter("userRegisterCachePenetrationBloomFilter");
        cachePenetrationBloomFilter.tryInit(100000000L, 0.001);
        return cachePenetrationBloomFilter;
    }
}

1
2
3
4
5
6
7
8
9
10
11
12

接口：

@GetMapping("/api/short-link/admin/v1/user/has-username")
public Result<Boolean> hasUsername(@RequestParam("username") String username) {
    return Results.success(userService.hasUsername(username));
}

1
2
3
4

private final RBloomFilter<String> userRegisterCachePenetrationBloomFilter;

// ...

@Override
public Boolean hasUsername(String username) {
    return !userRegisterCachePenetrationBloomFilter.contains(username);
}

1
2
3
4
5
6
7
8

← 实体类用户注册→