uuid

https://malaoshi.top/show_1C71GXLii5f2.html

twitter snowflake

https://github.com/twitter-archive/snowflake

java实现

https://malaoshi.top/show_1IXesi30dDY.html

滴滴的tinyid

https://github.com/didi/tinyid

百度 UidGenerator

https://github.com/baidu/uid-generator

美团 Leaf：

https://github.com/zhuzhong/idleaf