SpringBoot整合redis实现计数器限流的示例

<!-- springboot已集成，不需要再引入版本 -->
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

private void validRateBasic (String phone) {
        String key = "LIMIT:RATE:" + phone;
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(new StringRedisSerializer());
        try {
            String num = (String) redisTemplate.opsForValue().get(key);
            if (ObjectUtil.isNull(num)) {
                redisTemplate.opsForValue().set(key, "1", 60, TimeUnit.SECONDS);
            } else if (Integer.parseInt(num) >= 20) {
                Long expire = redisTemplate.getExpire(key);
                throw new CheckedException("操作频繁，请" + expire + "s后再试");
            } else {
                redisTemplate.opsForValue().increment(key);
            }
        } catch (Exception e) {
            if (e instanceof CheckedException) {
                throw new CheckedException(e.getMessage());
            } else {
                log.info("校验上传速率失败,error:{}",e);
                throw new CheckedException("操作失败，请稍后再试");
            }
        }

    }

private void validRate(String phone) {
        String key = "LIMIT:RATE:" + phone;SpringBoot整合redis实现计数器限流
        int retryTimes = 0;
        // 失败重试五次
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(new StringRedisSerializer());
        while(retryTimes < 6) {
            retryTimes++;
            try {
                // 在事务之外获取这个键的值
                String num = (String) redisTemplate.opsForValue().get(key);

                // 使用SessionCallback进行原子性操作
                SessionCallback<Object> sessionCallback = new SessionCallback<Object>() {
                    @Override
                    public Object execute(RedisOperations operations) throws DataAccessException {
                        operations.watch(key);
                        operations.multi();
                        // 在事务内部再次检查这个键的值
                        String currentNum = (String) operations.opsForValue().get(key);
                        if (num == null ? currentNum != null : !num.equals(currentNum)) {
                            // 这个键的值被修改了，所以取消这个事务
                            operations.discard();
                            return null;
                        }
                        if (ObjectUtil.isNull(num)) {
                            operations.opsForValue().set(key, "1", 60, TimeUnit.SECONDS);
                        } else if (Integer.parseInt(num) >= 5) {
                            Long expire = operations.getExpire(key);
                            throw new CheckedException("操作频繁，请" + expire + "s后再试");
                        } else {
                            operations.opsForValue().increment(key);
                        }
                        // 提交事务并返回结果
                        return operations.exec();
                    }
                };

                // 执行SessionCallback
                List<Object> results = (List<Object>) redisTemplate.execute(sessionCallback);
                if (CollectionUtils.isEmpty(results)) {
                    // 如果事务执行失败，重新尝试事务
                    log.info("重试");
                    continue;
                }
                return;
            } catch (Exception e) {
                // 在重试的情况下捕获任何异常
                if (retryTimes >= 5) {
                    throw new CheckedException("操作频繁，请稍后再试");
                }
            }
        }
    }

private void validRateLua(String phone) {
        String key = "LIMIT:RATE:" + phone;
        int retryTimes = 0;
        // 创建Lua脚本，返回新的计数值
        String luaScript =
                "local num = redis.call('GET', KEYS[1]);" +
                        "if num == false then " +
                        "   redis.call('SET', KEYS[1], ARGV[1], 'EX', ARGV[2]);" +
                        "   return ARGV[1];" +
                        "elseif tonumber(num) <= tonumber(ARGV[3]) then " +
                        "   local newNum = redis.call('INCR', KEYS[1]);" +
                        "   return newNum;" +
                        "else " +
                        "   return num;" +
                        "end;";
        RedisScript<String> redisScript = new DefaultRedisScript<>(luaScript, String.class);
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(new StringRedisSerializer());
        while(retryTimes < 5) {
            retryTimes++;
            try {
                // 执行Lua脚本
                String num = (String) redisTemplate.execute(redisScript, Collections.singletonList(key), "1", "60","5");
                if (num != null && Integer.parseInt(num) > 5) {
                    Long expire = redisTemplate.getExpire(key);
                    throw new CheckedException("操作频繁，请" + expire + "s后再试");
                }

                return;
            } catch (Exception e) {
                if (e instanceof CheckedException) {
                    throw new CheckedException(e.getMessage());
                } else {
                    // 在重试的情况下捕获任何异常
                    // 有需要的可以加入指数退避、最大重试时间等
                    if (retryTimes >= 5) {
                        log.error("上传失败,error:{}",e);
                        throw new CheckedException("操作频繁，请稍后再试");
                    }
                }
            }
        }
    }