void TestRaft_server_entry_is_retrieveable_using_idx(CuTest* tc)
{
raft_entry_t e1;
raft_entry_t e2;
raft_entry_t *ety_appended;
char *str = "aaa";
char *str2 = "bbb";
void *r = raft_new();
e1.term = 1;
e1.id = 1;
e1.data.buf = str;
e1.data.len = 3;
raft_append_entry(r, &e1);
/* different ID so we can be successful */
e2.term = 1;
e2.id = 2;
e2.data.buf = str2;
e2.data.len = 3;
raft_append_entry(r, &e2);
CuAssertTrue(tc, NULL != (ety_appended = raft_get_entry_from_idx(r, 2)));
CuAssertTrue(tc, !strncmp(ety_appended->data.buf, str2, 3));
}
/* Candidate 5.2 */
void TestRaft_follower_dont_grant_vote_if_candidate_has_a_less_complete_log(
CuTest * tc)
{
msg_requestvote_t rv;
msg_requestvote_response_t rvr;
void *r = raft_new();
raft_add_node(r, (void*)1, 1);
raft_add_node(r, (void*)2, 0);
/* request vote */
/* vote indicates candidate's log is not complete compared to follower */
memset(&rv, 0, sizeof(msg_requestvote_t));
rv.term = 1;
rv.candidate_id = 1;
rv.last_log_idx = 1;
rv.last_log_term = 1;
/* server's term and idx are more up-to-date */
raft_set_current_term(r, 1);
raft_entry_t ety;
ety.term = 1;
ety.id = 100;
ety.data.len = 4;
ety.data.buf = (unsigned char*)"aaa";
raft_append_entry(r, &ety);
ety.id = 101;
raft_append_entry(r, &ety);
/* vote not granted */
raft_recv_requestvote(r, 1, &rv, &rvr);
CuAssertTrue(tc, 0 == rvr.vote_granted);
}
/* 5.3 */
void
TestRaft_follower_recv_appendentries_delete_entries_if_conflict_with_new_entries(
CuTest * tc)
{
msg_appendentries_t ae;
msg_appendentries_response_t aer;
raft_entry_t *ety_appended;
void *r = raft_new();
raft_add_node(r, (void*)1, 1);
raft_add_node(r, (void*)2, 0);
raft_set_current_term(r, 1);
raft_entry_t ety;
/* increase log size */
char *str1 = "111";
ety.data.buf = str1;
ety.data.len = 3;
ety.id = 1;
ety.term = 1;
raft_append_entry(r, &ety);
CuAssertTrue(tc, 1 == raft_get_log_count(r));
/* this log will be overwritten by the appendentries below */
char *str2 = "222";
ety.data.buf = str2;
ety.data.len = 3;
ety.id = 2;
ety.term = 1;
raft_append_entry(r, &ety);
CuAssertTrue(tc, 2 == raft_get_log_count(r));
CuAssertTrue(tc, NULL != (ety_appended = raft_get_entry_from_idx(r, 2)));
CuAssertTrue(tc, !strncmp(ety_appended->data.buf, str2, 3));
/* pass a appendentry that is newer */
msg_entry_t mety;
memset(&ae, 0, sizeof(msg_appendentries_t));
ae.term = 2;
ae.prev_log_idx = 1;
ae.prev_log_term = 1;
/* include one entry */
memset(&mety, 0, sizeof(msg_entry_t));
char *str3 = "333";
mety.data.buf = str3;
mety.data.len = 3;
mety.id = 3;
ae.entries = &mety;
ae.n_entries = 1;
raft_recv_appendentries(r, 1, &ae, &aer);
CuAssertTrue(tc, 1 == aer.success);
CuAssertTrue(tc, 2 == raft_get_log_count(r));
CuAssertTrue(tc, NULL != (ety_appended = raft_get_entry_from_idx(r, 1)));
CuAssertTrue(tc, !strncmp(ety_appended->data.buf, str1, 3));
}
/* 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 TestRaft_server_idx_starts_at_1(CuTest * tc)
{
void *r = raft_new();
CuAssertTrue(tc, 0 == raft_get_current_idx(r));
raft_entry_t ety;
ety.data.buf = "aaa";
ety.data.len = 3;
ety.id = 1;
ety.term = 1;
raft_append_entry(r, &ety);
CuAssertTrue(tc, 1 == raft_get_current_idx(r));
}
int raft_recv_entry(raft_server_t* me_,
msg_entry_t* e,
msg_entry_response_t *r)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
int i;
/* Only one voting cfg change at a time */
if (raft_entry_is_voting_cfg_change(e))
if (-1 != me->voting_cfg_change_log_idx)
return -1;
if (!raft_is_leader(me_))
return -1;
__log(me_, NULL, "received entry t:%d id: %d idx: %d",
me->current_term, e->id, raft_get_current_idx(me_) + 1);
raft_entry_t ety;
ety.term = me->current_term;
ety.id = e->id;
ety.type = e->type;
memcpy(&ety.data, &e->data, sizeof(raft_entry_data_t));
raft_append_entry(me_, &ety);
for (i = 0; i < me->num_nodes; i++)
{
if (me->node == me->nodes[i] || !me->nodes[i] ||
!raft_node_is_voting(me->nodes[i]))
continue;
/* Only send new entries.
* Don't send the entry to peers who are behind, to prevent them from
* becoming congested. */
int next_idx = raft_node_get_next_idx(me->nodes[i]);
if (next_idx == raft_get_current_idx(me_))
raft_send_appendentries(me_, me->nodes[i]);
}
/* if we're the only node, we can consider the entry committed */
if (1 == me->num_nodes)
me->commit_idx = raft_get_current_idx(me_);
r->id = e->id;
r->idx = raft_get_current_idx(me_);
r->term = me->current_term;
if (raft_entry_is_voting_cfg_change(e))
me->voting_cfg_change_log_idx = raft_get_current_idx(me_);
return 0;
}
void TestRaft_server_entry_append_cant_append_if_id_is_zero(CuTest* tc)
{
raft_entry_t ety;
char *str = "aaa";
ety.data.buf = str;
ety.data.len = 3;
ety.id = 0;
ety.term = 1;
void *r = raft_new();
CuAssertTrue(tc, 0 == raft_get_current_idx(r));
raft_append_entry(r, &ety);
CuAssertTrue(tc, 0 == raft_get_current_idx(r));
}
/* TODO: no support for duplicate detection yet */
void
T_estRaft_server_append_entry_not_sucessful_if_entry_with_id_already_appended(
CuTest* tc)
{
void *r;
raft_entry_t ety;
char *str = "aaa";
ety.data.buf = str;
ety.data.len = 3;
ety.id = 1;
ety.term = 1;
r = raft_new();
CuAssertTrue(tc, 1 == raft_get_current_idx(r));
raft_append_entry(r, &ety);
raft_append_entry(r, &ety);
CuAssertTrue(tc, 2 == raft_get_current_idx(r));
/* different ID so we can be successful */
ety.id = 2;
raft_append_entry(r, &ety);
CuAssertTrue(tc, 3 == raft_get_current_idx(r));
}
void TestRaft_server_append_entry_means_entry_gets_current_term(CuTest* tc)
{
raft_entry_t ety;
char *str = "aaa";
ety.data.buf = str;
ety.data.len = 3;
ety.id = 1;
ety.term = 1;
void *r = raft_new();
CuAssertTrue(tc, 0 == raft_get_current_idx(r));
raft_append_entry(r, &ety);
CuAssertTrue(tc, 1 == raft_get_current_idx(r));
}
void TestRaft_server_apply_entry_increments_last_applied_idx(CuTest* tc)
{
raft_entry_t ety;
char *str = "aaa";
ety.term = 1;
void *r = raft_new();
raft_set_commit_idx(r, 1);
raft_set_last_applied_idx(r, 0);
ety.id = 1;
ety.data.buf = str;
ety.data.len = 3;
raft_append_entry(r, &ety);
raft_apply_entry(r);
CuAssertTrue(tc, 1 == raft_get_last_applied_idx(r));
}
int raft_recv_entry(raft_server_t* me_, int node, msg_entry_t* e)
{
raft_server_private_t* me = (void*)me_;
raft_entry_t ety;
int res, i;
__log(me_, NULL, "received entry from: %d", node);
ety.term = me->current_term;
ety.id = e->id;
ety.data = e->data;
ety.len = e->len;
res = raft_append_entry(me_, &ety);
raft_send_entry_response(me_, node, e->id, res);
for (i=0; i<me->num_nodes; i++)
{
if (me->nodeid == i) continue;
raft_send_appendentries(me_,i);
}
return 0;
}
int raft_recv_entry(raft_server_t* me_, int node, msg_entry_t* e,
msg_entry_response_t *r)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
raft_entry_t ety;
int res, i;
__log(me_, "received entry from: %d", node);
ety.term = me->current_term;
ety.id = e->id;
ety.data = e->data;
ety.len = e->len;
res = raft_append_entry(me_, &ety);
for (i = 0; i < me->num_nodes; i++)
if (me->nodeid != i)
raft_send_appendentries(me_, i);
r->id = e->id;
r->was_committed = (0 == res);
return 0;
}
void TestRaft_server_wont_apply_entry_if_we_dont_have_entry_to_apply(CuTest* tc)
{
raft_entry_t ety;
char *str = "aaa";
void *r = raft_new();
raft_set_commit_idx(r, 0);
raft_set_last_applied_idx(r, 0);
raft_apply_entry(r);
CuAssertTrue(tc, 0 == raft_get_last_applied_idx(r));
CuAssertTrue(tc, 0 == raft_get_commit_idx(r));
ety.term = 1;
ety.id = 1;
ety.data.buf = str;
ety.data.len = 3;
raft_append_entry(r, &ety);
raft_apply_entry(r);
CuAssertTrue(tc, 1 == raft_get_last_applied_idx(r));
CuAssertTrue(tc, 1 == raft_get_commit_idx(r));
}
int raft_recv_appendentries(
raft_server_t* me_,
const int node,
msg_appendentries_t* ae)
{
int i;
raft_server_private_t* me = (void*)me_;
msg_appendentries_response_t r;
me->timeout_elapsed = 0;
__log(me_, NULL, "received appendentries from: %d", node);
r.term = me->current_term;
/* we've found a leader who is legitimate */
if (raft_is_leader(me_) && me->current_term <= ae->term)
raft_become_follower(me_);
/* 1. Reply false if term < currentTerm (�1) */
if (ae->term < me->current_term)
{
__log(me_, NULL, "AE term is less than current term");
r.success = 0;
goto done;
}
#if 0
if (-1 != ae->prev_log_idx &&
ae->prev_log_idx < raft_get_current_idx(me_))
{
__log(me_, NULL, "AE prev_idx is less than current idx");
r.success = 0;
goto done;
}
#endif
/* not the first appendentries we've received */
if (0 != ae->prev_log_idx)
{
raft_entry_t* e;
if ((e = raft_get_entry_from_idx(me_, ae->prev_log_idx)))
{
/* 2. Reply false if log doesn抰 contain an entry at prevLogIndex
whose term matches prevLogTerm (�3) */
if (e->term != ae->prev_log_term)
{
__log(me_, NULL, "AE term doesn't match prev_idx");
r.success = 0;
goto done;
}
/* 3. If an existing entry conflicts with a new one (same index
but different terms), delete the existing entry and all that
follow it (�3) */
raft_entry_t* e2;
if ((e2 = raft_get_entry_from_idx(me_, ae->prev_log_idx+1)))
{
log_delete(me->log, ae->prev_log_idx+1);
}
}
else
{
__log(me_, NULL, "AE no log at prev_idx");
r.success = 0;
goto done;
//assert(0);
}
}
/* 5. If leaderCommit > commitIndex, set commitIndex =
min(leaderCommit, last log index) */
if (raft_get_commit_idx(me_) < ae->leader_commit)
{
raft_entry_t* e;
if ((e = log_peektail(me->log)))
{
raft_set_commit_idx(me_, e->id < ae->leader_commit ?
e->id : ae->leader_commit);
while (1 == raft_apply_entry(me_));
}
}
if (raft_is_candidate(me_))
raft_become_follower(me_);
raft_set_current_term(me_, ae->term);
/* append all entries to log */
for (i=0; i<ae->n_entries; i++)
{
msg_entry_t* cmd;
raft_entry_t* c;
cmd = &ae->entries[i];
/* TODO: replace malloc with mempoll/arena */
c = malloc(sizeof(raft_entry_t));
c->term = me->current_term;
c->len = cmd->len;
c->id = cmd->id;
c->data = malloc(cmd->len);
memcpy(c->data, cmd->data, cmd->len);
if (0 == raft_append_entry(me_, c))
{
__log(me_, NULL, "AE failure; couldn't append entry");
r.success = 0;
goto done;
}
}
r.success = 1;
r.current_idx = raft_get_current_idx(me_);
r.first_idx = ae->prev_log_idx + 1;
done:
if (me->cb.send)
me->cb.send(me->cb_ctx, me, node, RAFT_MSG_APPENDENTRIES_RESPONSE,
(void*)&r, sizeof(msg_appendentries_response_t));
return 1;
}
int raft_recv_appendentries(
raft_server_t* me_,
const int node,
msg_appendentries_t* ae,
msg_appendentries_response_t *r
)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
me->timeout_elapsed = 0;
__log(me_, "received appendentries from: %d", node);
r->term = me->current_term;
/* we've found a leader who is legitimate */
if (raft_is_leader(me_) && me->current_term <= ae->term)
raft_become_follower(me_);
/* 1. Reply false if term < currentTerm (§5.1) */
if (ae->term < me->current_term)
{
__log(me_, "AE term is less than current term");
r->success = 0;
return 0;
}
#if 0
if (-1 != ae->prev_log_idx &&
ae->prev_log_idx < raft_get_current_idx(me_))
{
__log(me_, "AE prev_idx is less than current idx");
r->success = 0;
return 0;
}
#endif
/* not the first appendentries we've received */
if (0 != ae->prev_log_idx)
{
raft_entry_t* e = raft_get_entry_from_idx(me_, ae->prev_log_idx);
if (e)
{
/* 2. Reply false if log doesn't contain an entry at prevLogIndex
whose term matches prevLogTerm (§5.3) */
if (e->term != ae->prev_log_term)
{
__log(me_, "AE term doesn't match prev_idx");
r->success = 0;
return 0;
}
/* 3. If an existing entry conflicts with a new one (same index
but different terms), delete the existing entry and all that
follow it (§5.3) */
raft_entry_t* e2;
e2 = raft_get_entry_from_idx(me_, ae->prev_log_idx + 1);
if (e2)
log_delete(me->log, ae->prev_log_idx + 1);
}
else
{
__log(me_, "AE no log at prev_idx");
r->success = 0;
return 0;
}
}
/* 5. If leaderCommit > commitIndex, set commitIndex =
min(leaderCommit, last log index) */
if (raft_get_commit_idx(me_) < ae->leader_commit)
{
raft_entry_t* e = log_peektail(me->log);
if (e)
{
int id = e->id < ae->leader_commit ? e->id : ae->leader_commit;
raft_set_commit_idx(me_, id);
while (0 == raft_apply_entry(me_))
;
}
}
if (raft_is_candidate(me_))
raft_become_follower(me_);
raft_set_current_term(me_, ae->term);
int i;
/* append all entries to log */
for (i = 0; i < ae->n_entries; i++)
{
msg_entry_t* cmd = &ae->entries[i];
/* TODO: replace malloc with mempoll/arena */
raft_entry_t* c = (raft_entry_t*)malloc(sizeof(raft_entry_t));
c->term = me->current_term;
c->len = cmd->len;
c->id = cmd->id;
c->data = (unsigned char*)malloc(cmd->len);
memcpy(c->data, cmd->data, cmd->len);
if (-1 == raft_append_entry(me_, c))
{
__log(me_, "AE failure; couldn't append entry");
r->success = 0;
return -1;
}
}
r->success = 1;
r->current_idx = raft_get_current_idx(me_);
r->first_idx = ae->prev_log_idx + 1;
return 0;
}
int raft_recv_appendentries(
raft_server_t* me_,
raft_node_t* node,
msg_appendentries_t* ae,
msg_appendentries_response_t *r
)
{
raft_server_private_t* me = (raft_server_private_t*)me_;
me->timeout_elapsed = 0;
if (0 < ae->n_entries)
__log(me_, node, "recvd appendentries from: %lx, t:%d ci:%d lc:%d pli:%d plt:%d #%d",
node,
ae->term,
raft_get_current_idx(me_),
ae->leader_commit,
ae->prev_log_idx,
ae->prev_log_term,
ae->n_entries);
r->term = me->current_term;
if (raft_is_candidate(me_) && me->current_term == ae->term)
{
me->voted_for = -1;
raft_become_follower(me_);
}
else if (me->current_term < ae->term)
{
raft_set_current_term(me_, ae->term);
r->term = ae->term;
raft_become_follower(me_);
}
else if (ae->term < me->current_term)
{
/* 1. Reply false if term < currentTerm (§5.1) */
__log(me_, node, "AE term %d is less than current term %d",
ae->term, me->current_term);
goto fail_with_current_idx;
}
/* Not the first appendentries we've received */
/* NOTE: the log starts at 1 */
if (0 < ae->prev_log_idx)
{
raft_entry_t* e = raft_get_entry_from_idx(me_, ae->prev_log_idx);
if (!e)
{
__log(me_, node, "AE no log at prev_idx %d", ae->prev_log_idx);
goto fail_with_current_idx;
}
/* 2. Reply false if log doesn't contain an entry at prevLogIndex
whose term matches prevLogTerm (§5.3) */
if (raft_get_current_idx(me_) < ae->prev_log_idx)
goto fail_with_current_idx;
if (e->term != ae->prev_log_term)
{
__log(me_, node, "AE term doesn't match prev_term (ie. %d vs %d) ci:%d pli:%d",
e->term, ae->prev_log_term, raft_get_current_idx(me_), ae->prev_log_idx);
assert(me->commit_idx < ae->prev_log_idx);
/* Delete all the following log entries because they don't match */
log_delete(me->log, ae->prev_log_idx);
r->current_idx = ae->prev_log_idx - 1;
goto fail;
}
}
/* 3. If an existing entry conflicts with a new one (same index
but different terms), delete the existing entry and all that
follow it (§5.3) */
if (ae->n_entries == 0 && 0 < ae->prev_log_idx && ae->prev_log_idx + 1 < raft_get_current_idx(me_))
{
assert(me->commit_idx < ae->prev_log_idx + 1);
log_delete(me->log, ae->prev_log_idx + 1);
}
r->current_idx = ae->prev_log_idx;
int i;
for (i = 0; i < ae->n_entries; i++)
{
msg_entry_t* ety = &ae->entries[i];
int ety_index = ae->prev_log_idx + 1 + i;
raft_entry_t* existing_ety = raft_get_entry_from_idx(me_, ety_index);
r->current_idx = ety_index;
if (existing_ety && existing_ety->term != ety->term)
{
assert(me->commit_idx < ety_index);
log_delete(me->log, ety_index);
break;
}
else if (!existing_ety)
break;
}
/* Pick up remainder in case of mismatch or missing entry */
for (; i < ae->n_entries; i++)
{
int e = raft_append_entry(me_, &ae->entries[i]);
if (-1 == e)
goto fail_with_current_idx;
r->current_idx = ae->prev_log_idx + 1 + i;
}
/* 4. If leaderCommit > commitIndex, set commitIndex =
min(leaderCommit, index of most recent entry) */
if (raft_get_commit_idx(me_) < ae->leader_commit)
{
int last_log_idx = max(raft_get_current_idx(me_), 1);
raft_set_commit_idx(me_, min(last_log_idx, ae->leader_commit));
}
/* update current leader because we accepted appendentries from it */
me->current_leader = node;
r->success = 1;
r->first_idx = ae->prev_log_idx + 1;
return 0;
fail_with_current_idx:
r->current_idx = raft_get_current_idx(me_);
fail:
r->success = 0;
r->first_idx = 0;
return -1;
}
