libraft

Raft protocol implementation in C.

Features

• Leader Election
• Log Replication
• Log Compaction

Usage

1. Include raft.h and link with -lraft

2. Initialize: a. Populate a raft_config_t with parameters (host, port, timeouts, log length, etc.)

   b. Set an applier and a snapshooter callbacks. The applier should perform state modification, and the snapshooter should dump the state. See raft.h for their signatures.

   c. Call raft_init(cfg).

   d. Use raft_peer_up(...) to configure the peers, including the current one.

   e. Create and bind the socket with raft_create_udp_socket(...).

3. Serve raft: a. Call raft_tick(...) frequently to perform the logic of timeouts.

   b. Try to extract a message with raft_recv_message(...) when you believe there is one in the socket.

   c. Call raft_handle_message(...) when a message has been successfully extracted from the socket.

4. Serve clients: a. If this server is a leader (call raft_get_leader(...) to find out), then it should accept pending connections and process client quieries.

   b. Use raft_emit(...) to update the state though raft. Then wait until raft_applied(...) before returning the result to the client.

   c. You may use raft_get_leader(...) to redirect clients to the leader, though this is not necessary.

Please read raft.h and example/ for more details.

Testing

1. Install docker and blockade.
2. You may want to gain superuser privileges at this point.
3. $ make check

TODO

• Membership Changes