Lock service

[yfei-z]

A RAFT implementation of lock service

[jabolina]

Hey, @yfei-z. I'll take a look. Some things missing are a design document in the ./doc/design/ folder and expanding the Java docs at the LockService class. It should include information such as the guarantees, what happens in case of failures (node holding a lock, leader loss, majority loss, etc.), and, if necessary, usage patterns.

On a side note, I am skeptical about distributed locks, even in consensus. I am not the author, but I agree with https://belaban.blogspot.com/2020/11/i-hate-distributed-locks.html

[yfei-z]

Yes, I will complete the docs.

[yfei-z]

Hi @jabolina. I have finished the initial doc, and I will continue to improve it if I think of anything else, you can take a look.

[jabolina]

Thanks for the work, @yfei-z! I'll take a look.

[yfei-z]

I think the problem of the query command is that it could be failed. I will reconsider it. I am quit busy recently, I will do it as soon as possible.