A toy implementation of the Raft protocol, backing a consistent, persistent distributed log.
To run a three-node cluster with Docker:
make run
which does:
lein uberjar
docker-compose build
docker-compose up
The nodes will elect a leader (though sometimes it takes a little
while). After a leader has been elected, if you stop the leader with
docker-compose stop peerX, the remaining two nodes should elect a
new leader, and if you restart the dead node with docker-compose start peerX it should be able to rejoin the cluster.
Once the cluster is running, you can fetch the log or append an entry
via HTTP. The provided docker-compose.yml does not expose ports to
the host, so the easiest way is to run a shell in one of the
containers:
$ docker-compose exec peer1 /bin/bash
# curl peer2:3457/log -d "my first log entry"
"logd.raft/ok"
# curl peer2:3457/log
[{"term":8,"data":"my first log entry"}]
Run the unit tests with:
lein test