Current leaderboard

[malensek]

After #10 is implemented we need a way to view who has the most coins. This feature would read the log, tally up the coins mined for each user, sort the list, and print it nicely.

The feature can be implemented as server-side only, i.e., you would run it on the server and point it at the log file to produce the current leaderboard. But we could also conceivably expose this to clients as well via a message (perhaps after each coin is mined we would re-generate the leaderboard as a text file and then clients could ask for it whenever they want).

This task is worth 1.5 points.

[malensek]

Also if someone can lead the discussion on how to implement this, that'll be worth 0.5 points.

[Qianru69]

Whenever the server updates the leaderboard, we need to use a mutex lock. This is to make sure the clients will not get "out of date" information when there is a new update a few seconds ago.

[marcuskuan]

Maybe we can wrap it in the request_task. The leaderboard will only be updated after each task is finished so if we send it with request_task, then we don't have to worry about a lock or something else i.e. do it in the handle_heartbeat with current_task