实现关注、取消关注
value的数据类型时zset，有序集合，按照关注的时间排序followee:userId:entityType -> zset(entityId,now) 某个用户关注的实体(实体包括帖子、评论、用户),按照实体分别存follower:entityType:entityId -> zset(userId,now) 某个实体拥有的粉丝（实体包括帖子、评论、用户）
这个功能时异步请求
1、RedisKeyUtil
private static final String PREFIX_FOLLOWEE = "followee";private static final String PREFIX_FOLLOWER = "follower";// 某个用户关注的实体(实体包括帖子、用户)// followee:userId:entityType -> zset(entityId,now)public static String getFolloweeKey(int userId, int entityType) {return PREFIX_FOLLOWEE + SPLIT + userId + SPLIT + entityType;}// 某个实体拥有的粉丝（实体包括帖子、用户）// follower:entityType:entityId -> zset(userId,now)public static String getFollowerKey(int entityType, int entityId) {return PREFIX_FOLLOWER + SPLIT + entityType + SPLIT + entityId;}
2、FollowService
@Servicepublic class FollowService {@Autowiredprivate RedisTemplate redisTemplate;public void follow(int userId, int entityType, int entityId) {redisTemplate.execute(new SessionCallback() {@Overridepublic Object execute(RedisOperations operations) throws DataAccessException {// 某个用户关注的实体String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);// 某个实体拥有的粉丝String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);operations.multi();operations.opsForZSet().add(followeeKey, entityId, System.currentTimeMillis());operations.opsForZSet().add(followerKey, userId, System.currentTimeMillis());return operations.exec();}});}public void unfollow(int userId, int entityType, int entityId) {redisTemplate.execute(new SessionCallback() {@Overridepublic Object execute(RedisOperations operations) throws DataAccessException {String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);operations.multi();operations.opsForZSet().remove(followeeKey, entityId);operations.opsForZSet().remove(followerKey, userId);return operations.exec();}});}// 查询关注的实体的数量public long findFolloweeCount(int userId, int entityType) {String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);return redisTemplate.opsForZSet().zCard(followeeKey);}// 查询实体的粉丝的数量public long findFollowerCount(int entityType, int entityId){String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);return redisTemplate.opsForZSet().zCard(followerKey);}// 查询当前用户是否已关注该实体(该用户对这类实体的id有一个清单zset)public boolean hasFollowed(int userId, int entityType, int entityId) {String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);return redisTemplate.opsForZSet().score(followeeKey, entityId) != null;}}
3、profile.js
$(function(){$(".follow-btn").click(follow);});function follow() {var btn = this;if($(btn).hasClass("btn-info")) {// 关注TA$.post(CONTEXT_PATH + "/follow",{"entityType":3,"entityId":$(btn).prev().val()},function(data) {data = $.parseJSON(data);if(data.code == 0) {window.location.reload();} else {alert(data.msg);}});// $(btn).text("已关注").removeClass("btn-info").addClass("btn-secondary");} else {// 取消关注$.post(CONTEXT_PATH + "/unfollow",{"entityType":3,"entityId":$(btn).prev().val()},function(data) {data = $.parseJSON(data);if(data.code == 0) {window.location.reload();} else {alert(data.msg);}});//$(btn).text("关注TA").removeClass("btn-secondary").addClass("btn-info");}}
关注列表和粉丝列表
1、FollowService
// 查询某用户关注的人public List<Map<String, Object>> findFollowees(int userId, int offset, int limit) {String followeeKey = RedisKeyUtil.getFolloweeKey(userId, ENTITY_TYPE_USER);Set<Integer> targetIds = redisTemplate.opsForZSet().reverseRange(followeeKey, offset, offset + limit - 1);if (targetIds == null) {return null;}List<Map<String, Object>> list = new ArrayList<>();for (Integer targetId : targetIds) {Map<String, Object> map = new HashMap<>();User user = userService.findUserById(targetId);map.put("user", user);Double score = redisTemplate.opsForZSet().score(followeeKey, targetId);map.put("followTime", new Date(score.longValue()));list.add(map);}return list;}// 查询某用户的粉丝public List<Map<String, Object>> findFollowers(int userId, int offset, int limit) {String followerKey = RedisKeyUtil.getFollowerKey(ENTITY_TYPE_USER, userId);Set<Integer> targetIds = redisTemplate.opsForZSet().reverseRange(followerKey, offset, offset + limit + 1);if (targetIds == null) {return null;}List<Map<String, Object>> list = new ArrayList<>();for (Integer targetId : targetIds) {Map<String, Object> map = new HashMap<>();User user = userService.findUserById(targetId);map.put("user", user);Double score = redisTemplate.opsForZSet().score(followerKey, targetId);map.put("followTime", new Date(score.longValue()));list.add(map);}return list;}
2、FollowController
@RequestMapping(path = "/followees/{userId}", method = RequestMethod.GET)public String getFollowees(@PathVariable("userId") int userId, Page page, Model model) {User user = userService.findUserById(userId);if (user == null) {throw new RuntimeException("该用户不存在!");}model.addAttribute("user", user);page.setLimit(5);page.setPath("/followees/" + userId);page.setRows((int) followService.findFolloweeCount(userId, ENTITY_TYPE_USER));List<Map<String, Object>> userList = followService.findFollowees(userId, page.getOffset(), page.getLimit());if (userList != null) {for (Map<String, Object> map : userList) {User u = (User) map.get("user");map.put("hasFollowed", hasFollowed(u.getId()));}}model.addAttribute("users", userList);// 里面存了user、followTime、hasFollowedreturn "/site/followee";}@RequestMapping(path = "/followers/{userId}", method = RequestMethod.GET)public String getFollowers(@PathVariable("userId") int userId, Page page, Model model) {User user = userService.findUserById(userId);if (user == null) {throw new RuntimeException("该用户不存在!");}model.addAttribute("user", user);page.setLimit(5);page.setPath("/followers/" + userId);page.setRows((int) followService.findFollowerCount(ENTITY_TYPE_USER, userId));List<Map<String, Object>> userList = followService.findFollowers(userId, page.getOffset(), page.getLimit());if (userList != null) {for (Map<String, Object> map : userList) {User u = (User) map.get("user");map.put("hasFollowed", hasFollowed(u.getId()));}}model.addAttribute("users", userList);return "/site/follower";}private boolean hasFollowed(int userId) {if (hostHolder.getUser() == null) {return false;}return followService.hasFollowed(hostHolder.getUser().getId(), ENTITY_TYPE_USER, userId);}
