void TestRaft_follower_recv_appendentries_does_not_log_if_no_entries_are_specified(
CuTest * tc)
{
msg_appendentries_t ae;
msg_appendentries_response_t aer;
void *r = raft_new();
raft_add_node(r, (void*)1, 1);
raft_add_node(r, (void*)2, 0);
raft_set_state(r, RAFT_STATE_FOLLOWER);
/* log size s */
CuAssertTrue(tc, 0 == raft_get_log_count(r));
/* receive an appendentry with commit */
memset(&ae, 0, sizeof(msg_appendentries_t));
ae.term = 1;
ae.prev_log_term = 1;
ae.prev_log_idx = 4;
ae.leader_commit = 5;
ae.n_entries = 0;
raft_recv_appendentries(r, 1, &ae, &aer);
CuAssertTrue(tc, 0 == raft_get_log_count(r));
}
/* If commitidx > lastApplied: increment lastApplied, apply log[lastApplied]
* to state machine (§5.3) */
void TestRaft_server_increment_lastApplied_when_lastApplied_lt_commitidx(
CuTest* tc)
{
raft_entry_t ety;
void *r = raft_new();
/* must be follower */
raft_set_state(r, RAFT_STATE_FOLLOWER);
raft_set_current_term(r, 1);
raft_set_commit_idx(r, 1);
raft_set_last_applied_idx(r, 0);
/* need at least one entry */
ety.term = 1;
ety.id = 1;
ety.data.buf = "aaa";
ety.data.len = 3;
raft_append_entry(r, &ety);
/* let time lapse */
raft_periodic(r, 1);
CuAssertTrue(tc, 0 != raft_get_last_applied_idx(r));
CuAssertTrue(tc, 1 == raft_get_last_applied_idx(r));
}
void raft_become_follower(raft_server_t* me_)
{
raft_server_private_t* me = (void*)me_;
__log(me_, NULL, "becoming follower");
raft_set_state(me_, RAFT_STATE_FOLLOWER);
me->voted_for = -1;
}
raft_server_t* raft_new()
{
raft_server_private_t* me = (raft_server_private_t*)calloc(1, sizeof(raft_server_private_t));
if (!me)
return NULL;
me->current_term = 0;
me->voted_for = -1;
me->current_idx = 1;
me->timeout_elapsed = 0;
me->request_timeout = 200;
me->election_timeout = 1000;
me->log = log_new();
raft_set_state((raft_server_t*)me, RAFT_STATE_FOLLOWER);
return (raft_server_t*)me;
}
void raft_become_leader(raft_server_t* me_)
{
raft_server_private_t* me = (void*)me_;
int i;
__log(me_, NULL, "becoming leader");
raft_set_state(me_,RAFT_STATE_LEADER);
me->voted_for = -1;
for (i=0; i<me->num_nodes; i++)
{
if (me->nodeid == i) continue;
raft_node_t* p = raft_get_node(me_, i);
raft_node_set_next_idx(p, raft_get_current_idx(me_)+1);
raft_send_appendentries(me_, i);
}
}
void raft_clear(raft_server_t* me_)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
me->current_term = 0;
me->voted_for = -1;
me->timeout_elapsed = 0;
me->voting_cfg_change_log_idx = -1;
raft_set_state((raft_server_t*)me, RAFT_STATE_FOLLOWER);
me->current_leader = NULL;
me->commit_idx = 0;
me->last_applied_idx = 0;
me->num_nodes = 0;
me->node = NULL;
me->voting_cfg_change_log_idx = 0;
log_clear(me->log);
}
void raft_become_leader(raft_server_t* me_)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
int i;
__log(me_, NULL, "becoming leader term:%d", raft_get_current_term(me_));
raft_set_state(me_, RAFT_STATE_LEADER);
for (i = 0; i < me->num_nodes; i++)
{
if (me->node == me->nodes[i] || !raft_node_is_voting(me->nodes[i]))
continue;
raft_node_t* node = me->nodes[i];
raft_node_set_next_idx(node, raft_get_current_idx(me_) + 1);
raft_node_set_match_idx(node, 0);
raft_send_appendentries(me_, node);
}
}
void raft_become_candidate(raft_server_t* me_)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
int i;
__log(me_, "becoming candidate");
memset(me->votes_for_me, 0, sizeof(int) * me->num_nodes);
me->current_term += 1;
raft_vote(me_, me->nodeid);
raft_set_state(me_, RAFT_STATE_CANDIDATE);
/* we need a random factor here to prevent simultaneous candidates */
me->timeout_elapsed = rand() % 500;
for (i = 0; i < me->num_nodes; i++)
if (me->nodeid != i)
raft_send_requestvote(me_, i);
}
void raft_become_candidate(raft_server_t* me_)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
int i;
__log(me_, NULL, "becoming candidate");
raft_set_current_term(me_, raft_get_current_term(me_) + 1);
for (i = 0; i < me->num_nodes; i++)
raft_node_vote_for_me(me->nodes[i], 0);
raft_vote(me_, me->node);
me->current_leader = NULL;
raft_set_state(me_, RAFT_STATE_CANDIDATE);
/* we need a random factor here to prevent simultaneous candidates */
/* TODO: this should probably be lower */
me->timeout_elapsed = rand() % me->election_timeout;
for (i = 0; i < me->num_nodes; i++)
if (me->node != me->nodes[i] && raft_node_is_voting(me->nodes[i]))
raft_send_requestvote(me_, me->nodes[i]);
}
void TestRaft_follower_recv_appendentries_increases_log(CuTest * tc)
{
msg_appendentries_t ae;
msg_entry_t ety;
msg_appendentries_response_t aer;
char *str = "aaa";
void *r = raft_new();
raft_add_node(r, (void*)1, 1);
raft_add_node(r, (void*)2, 0);
raft_set_state(r, RAFT_STATE_FOLLOWER);
/* log size s */
CuAssertTrue(tc, 0 == raft_get_log_count(r));
/* receive an appendentry with commit */
memset(&ae, 0, sizeof(msg_appendentries_t));
ae.term = 3;
ae.prev_log_term = 1;
/* first appendentries msg */
ae.prev_log_idx = 0;
ae.leader_commit = 5;
/* include one entry */
memset(&ety, 0, sizeof(msg_entry_t));
ety.data.buf = str;
ety.data.len = 3;
ety.id = 1;
/* check that old terms are passed onto the log */
ety.term = 2;
ae.entries = &ety;
ae.n_entries = 1;
raft_recv_appendentries(r, 1, &ae, &aer);
CuAssertTrue(tc, 1 == aer.success);
CuAssertTrue(tc, 1 == raft_get_log_count(r));
raft_entry_t* log = raft_get_entry_from_idx(r, 1);
CuAssertTrue(tc, 2 == log->term);
}
void raft_become_follower(raft_server_t* me_)
{
__log(me_, NULL, "becoming follower");
raft_set_state(me_, RAFT_STATE_FOLLOWER);
}
void TestRaft_set_state(CuTest * tc)
{
void *r = raft_new();
raft_set_state(r, RAFT_STATE_LEADER);
CuAssertTrue(tc, RAFT_STATE_LEADER == raft_get_state(r));
}