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#include "../lib/cluster.h"
#include "../lib/runner.h"
/******************************************************************************
*
* Fixture
*
*****************************************************************************/
struct fixture
{
FIXTURE_CLUSTER;
};
static void *setUp(const MunitParameter params[], MUNIT_UNUSED void *user_data)
{
struct fixture *f = munit_malloc(sizeof *f);
SETUP_CLUSTER();
return f;
}
static void tearDown(void *data)
{
struct fixture *f = data;
TEAR_DOWN_CLUSTER();
free(f);
}
SUITE(tick)
/* If the election timeout expires, the follower is a voting server, and it
* hasn't voted yet in this term, then become candidate and start a new
* election. */
TEST(tick, ConvertToCandidate, setUp, tearDown, 0, NULL)
{
struct fixture *f = data;
struct raft *raft;
unsigned id;
/* Bootstrap and start a cluster with 2 voters. */
for (id = 1; id <= 2; id++) {
CLUSTER_SET_TERM(id, 1 /* term */);
CLUSTER_ADD_ENTRY(id, RAFT_CHANGE, 2 /* servers */, 2 /* voters */);
CLUSTER_START(id);
}
/* Server 1 becomes leader */
CLUSTER_TRACE(
"[ 0] 1 > term 1, 1 entry (1^1)\n"
"[ 0] 2 > term 1, 1 entry (1^1)\n"
"[ 100] 1 > timeout as follower\n"
" convert to candidate, start election for term 2\n"
"[ 110] 2 > recv request vote from server 1\n"
" remote term is higher (2 vs 1) -> bump term\n"
" remote log is equal (1^1) -> grant vote\n"
"[ 120] 1 > recv request vote result from server 2\n"
" quorum reached with 2 votes out of 2 -> convert to leader\n"
" probe server 2 sending a heartbeat (no entries)\n");
/* Stop server 1, eventually server 2 converts to candidate. */
CLUSTER_STOP(1);
CLUSTER_TRACE(
"[ 240] 2 > timeout as follower\n"
" convert to candidate, start election for term 3\n");
/* The term has been incremeted. */
raft = CLUSTER_RAFT(2);
munit_assert_ullong(raft_current_term(raft), ==, 3);
/* We have voted for ouselves. */
munit_assert_ullong(raft_voted_for(raft), ==, 2);
/* We are candidate */
munit_assert_int(raft_state(raft), ==, RAFT_CANDIDATE);
/* The vote results array is initialized */
munit_assert_ptr_not_null(raft->candidate_state.votes);
munit_assert_false(raft->candidate_state.votes[0].grant);
munit_assert_true(raft->candidate_state.votes[1].grant);
return MUNIT_OK;
}
static char *elapse_non_voter_n_voting[] = {"1", NULL};
static MunitParameterEnum elapse_non_voter_params[] = {
{"n_voting", elapse_non_voter_n_voting},
{NULL, NULL},
};
/* If the election timeout has elapsed, but we're not part of the current
* configuration, stay follower. */
TEST(tick, NotInCurrentConfiguration, setUp, tearDown, 0, NULL)
{
struct fixture *f = data;
CLUSTER_SET_TERM(2, 1 /* term */);
CLUSTER_ADD_ENTRY(2, RAFT_CHANGE, 1 /* servers */, 1 /* voters */);
CLUSTER_START(2);
CLUSTER_TRACE(
"[ 0] 2 > term 1, 1 entry (1^1)\n"
"[ 130] 2 > timeout as follower\n"
" server not in current configuration -> stay follower\n");
munit_assert_int(raft_state(CLUSTER_RAFT(2)), ==, RAFT_FOLLOWER);
return MUNIT_OK;
}
/* If the election timeout has elapsed, but we're not voters, stay follower. */
TEST(tick, NotVoter, setUp, tearDown, 0, elapse_non_voter_params)
{
struct fixture *f = data;
CLUSTER_SET_TERM(2, 1 /* term */);
CLUSTER_ADD_ENTRY(2, RAFT_CHANGE, 2 /* servers */, 1 /* voters */);
CLUSTER_START(2);
CLUSTER_TRACE(
"[ 0] 2 > term 1, 1 entry (1^1)\n"
"[ 130] 2 > timeout as follower\n"
" spare server -> stay follower\n");
munit_assert_int(raft_state(CLUSTER_RAFT(2)), ==, RAFT_FOLLOWER);
return MUNIT_OK;
}
/* If we're leader and an election timeout elapses without hearing from a
* majority of the cluster, step down. */
TEST(tick, StepDownIfNoContact, setUp, tearDown, 0, NULL)
{
struct fixture *f = data;
unsigned id;
/* Bootstrap and start a cluster with 2 voters. */
for (id = 1; id <= 2; id++) {
CLUSTER_SET_TERM(id, 1 /* term */);
CLUSTER_ADD_ENTRY(id, RAFT_CHANGE, 2 /* servers */, 2 /* voters */);
CLUSTER_START(id);
}
/* Server 1 becomes leader */
CLUSTER_TRACE(
"[ 0] 1 > term 1, 1 entry (1^1)\n"
"[ 0] 2 > term 1, 1 entry (1^1)\n"
"[ 100] 1 > timeout as follower\n"
" convert to candidate, start election for term 2\n"
"[ 110] 2 > recv request vote from server 1\n"
" remote term is higher (2 vs 1) -> bump term\n"
" remote log is equal (1^1) -> grant vote\n"
"[ 120] 1 > recv request vote result from server 2\n"
" quorum reached with 2 votes out of 2 -> convert to leader\n"
" probe server 2 sending a heartbeat (no entries)\n");
/* Stop server 2, eventually server 1 steps down. */
CLUSTER_STOP(2);
CLUSTER_TRACE(
"[ 170] 1 > timeout as leader\n"
" probe server 2 sending a heartbeat (no entries)\n"
"[ 220] 1 > timeout as leader\n"
" unable to contact majority of cluster -> step down\n");
return MUNIT_OK;
}
/* If we're candidate and the election timeout has elapsed, start a new
* election. */
TEST(tick, NewElection, setUp, tearDown, 0, NULL)
{
struct fixture *f = data;
CLUSTER_SET_TERM(1, 1 /* term */);
CLUSTER_ADD_ENTRY(1, RAFT_CHANGE, 2 /* servers */, 2 /* voters */);
CLUSTER_START(1);
/* Server 1 becomes candidate. */
CLUSTER_TRACE(
"[ 0] 1 > term 1, 1 entry (1^1)\n"
"[ 100] 1 > timeout as follower\n"
" convert to candidate, start election for term 2\n");
CLUSTER_TRACE(
"[ 200] 1 > timeout as candidate\n"
" stay candidate, start election for term 3\n");
return MUNIT_OK;
}
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