redisTemplate 模糊查询

场景

线上有百万级别的 key , 要求模糊查询,并删除

模糊查询

想当然就是 keys, 不过 大量的 key 加载会阻塞 redis, 影响其他业务调用 , 所以选择 scan

public Set<String> fuzzySearch(String pattern) {
    Set<String> keys = new HashSet<>();
    Cursor<byte[]> cursor = null;
    try {
        cursor = (Cursor) redisTemplate.execute((RedisCallback) redisConnection -> redisConnection.scan(ScanOptions.scanOptions().match(pattern).count(10000).build()));
        if (cursor==null || cursor.getCursorId()==0){
            return Collections.emptySet();
        }
        while (cursor.hasNext()) {
            keys.add(new String(cursor.next()));
        }
    } catch (Exception e) {
       
    } finally {
        if (cursor != null) {
            try {
                cursor.close();
            } catch (IOException e) {
              //....
            }
        }
    }
    return keys;
}

scan 并不能解决CUP竞争问题,只是优化内存加载问题!!