@RestController
@RequestMapping("/blog")
public class BlogController {
@Resource
private IBlogService blogService;
// 发布探店笔记
@PostMapping
public Result saveBlog(@RequestBody Blog blog) {
return blogService.saveBlog(blog);
}
// 查看笔记详情
@GetMapping("/{id}")
public Result queryBlogById(@PathVariable Long id) {
return blogService.queryBlogById(id);
}
// 点赞/取消点赞
@PutMapping("/like/{id}")
public Result likeBlog(@PathVariable Long id) {
return blogService.likeBlog(id);
}
// 点赞排行榜 Top5
@GetMapping("/likes/{id}")
public Result queryBlogLikes(@PathVariable Long id) {
return blogService.queryBlogLikes(id);
}
// 分页查询热门笔记
@GetMapping("/hot")
public Result queryHotBlog(@RequestParam(value = "current", defaultValue = "1") Integer current) {
return blogService.queryHotBlog(current);
}
}
4. IBlogService
java复制代码
public interface IBlogService extends IService<Blog> {
Result saveBlog(Blog blog);
Result queryBlogById(Long id);
Result likeBlog(Long id);
Result queryBlogLikes(Long id);
Result queryHotBlog(Integer current);
}
5. BlogServiceImpl（核心业务）
java复制代码
@Service
public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IBlogService {
@Resource
private IUserService userService;
@Resource
private StringRedisTemplate stringRedisTemplate;
public static final String BLOG_LIKED_KEY = "blog:liked:";
// 发布笔记
@Override
public Result saveBlog(Blog blog) {
// 1.获取登录用户
UserDTO user = UserHolder.getUser();
blog.setUserId(user.getId());
// 2.保存探店笔记
boolean save = save(blog);
if (!save) {
return Result.fail("发布笔记失败");
}
// 3.返回笔记id
return Result.ok(blog.getId());
}
// 查询笔记详情
@Override
public Result queryBlogById(Long id) {
// 1.查询blog
Blog blog = getById(id);
if (blog == null) {
return Result.fail("笔记不存在！");
}
// 2.查询发布者信息
queryBlogUser(blog);
// 3.查询是否被当前用户点赞
isBlogLiked(blog);
return Result.ok(blog);
}
// 点赞/取消点赞（ZSet 实现）
@Override
public Result likeBlog(Long id) {
// 1.获取登录用户
Long userId = UserHolder.getUser().getId();
String key = BLOG_LIKED_KEY + id;
// 2.判断是否点赞过
Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());
if (score == null) {
// 3.未点赞：数据库+1，Redis保存
boolean success = update().setSql("liked = liked + 1").eq("id", id).update();
if (success) {
stringRedisTemplate.opsForZSet().add(key, userId.toString(), System.currentTimeMillis());
}
} else {
// 4.已点赞：数据库-1，Redis移除
boolean success = update().setSql("liked = liked - 1").eq("id", id).update();
if (success) {
stringRedisTemplate.opsForZSet().remove(key, userId.toString());
}
}
return Result.ok();
}
// 点赞排行榜 Top5
@Override
public Result queryBlogLikes(Long id) {
String key = BLOG_LIKED_KEY + id;
// 1.查询 Top5 用户id
Set<String> top5 = stringRedisTemplate.opsForZSet().range(key, 0, 4);
if (CollUtil.isEmpty(top5)) {
return Result.ok(Collections.emptyList());
}
// 2.转换id
List<Long> ids = top5.stream().map(Long::valueOf).collect(Collectors.toList());
String idStr = StrUtil.join(",", ids);
// 3.根据id查询用户，并保持排序
List<UserDTO> userDTOList = userService.query()
.in("id", ids)
.last("ORDER BY FIELD(id," + idStr + ")")
.list()
.stream()
.map(user -> BeanUtil.copyProperties(user, UserDTO.class))
.collect(Collectors.toList());
return Result.ok(userDTOList);
}
// 分页查询热门笔记
@Override
public Result queryHotBlog(Integer current) {
Page<Blog> page = this.query()
.orderByDesc("liked")
.page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
List<Blog> records = page.getRecords();
// 封装用户信息和点赞状态
records.forEach(blog -> {
queryBlogUser(blog);
isBlogLiked(blog);
});
return Result.ok(records);
}
// 封装：查询发布者信息
private void queryBlogUser(Blog blog) {
Long userId = blog.getUserId();
User user = userService.getById(userId);
blog.setName(user.getNickName());
blog.setIcon(user.getIcon());
}
// 封装：判断当前用户是否点赞
private void isBlogLiked(Blog blog) {
UserDTO user = UserHolder.getUser();
if (user == null) {
blog.setIsLike(false);
return;
}
Long userId = user.getId();
String key = BLOG_LIKED_KEY + blog.getId();
Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());
blog.setIsLike(score != null);
}
}