Server side race conditions #16
Description
There are race conditions possible in some scenarios on the server-side because app engine can create multiple instances of our java servlets. For example:
- While choosing game code, two instances can see that the same game code is not in use (concurrently) and then both can attempt to use it.
- When players are joining, there could be a race condition in seeing how many players have already joined. (two instances get the request from two players to join the same room and see there are 9 players and both permit the request and we end up with 11 players)