def debug_statistics(self):
return {
"node":
lib.raft_get_nodeid(self.raft),
"state":
state2str(lib.raft_get_state(self.raft)),
"current_idx":
lib.raft_get_current_idx(self.raft),
"last_log_term":
lib.raft_get_last_log_term(self.raft),
"current_term":
lib.raft_get_current_term(self.raft),
"commit_idx":
lib.raft_get_commit_idx(self.raft),
"last_applied_idx":
lib.raft_get_last_applied_idx(self.raft),
"log_count":
lib.raft_get_log_count(self.raft),
"peers":
lib.raft_get_num_nodes(self.raft),
"voting_peers":
lib.raft_get_num_voting_nodes(self.raft),
"connection_status":
connectstatus2str(self.connection_status),
"voting_change_in_progress":
lib.raft_voting_change_is_in_progress(self.raft),
"removed":
getattr(self, 'removed', False),
}
def _check_election_safety(self):
"""
FIXME: this is O(n^2)
Election Safety
At most one leader can be elected in a given term.
"""
for i, sv1 in enumerate(net.active_servers):
if not lib.raft_is_leader(sv1.raft):
continue
for sv2 in net.active_servers[i + 1:]:
term1 = lib.raft_get_current_term(sv1.raft)
term2 = lib.raft_get_current_term(sv2.raft)
if lib.raft_is_leader(sv2.raft) and term1 == term2:
logging.error("election safety invalidated")
print(sv1, sv2, term1)
print('partitions:', self.partitions)
sys.exit(1)
def load_snapshot(self, snapshot, other):
# logging.warning('{} loading snapshot'.format(self))
e = lib.raft_begin_load_snapshot(
self.raft,
snapshot.last_term,
snapshot.last_idx,
)
if e == -1:
return 0
elif e == lib.RAFT_ERR_SNAPSHOT_ALREADY_LOADED:
return 0
elif e == 0:
pass
else:
assert False
# Send appendentries response for this snapshot
response = ffi.new('msg_appendentries_response_t*')
response.success = 1
response.current_idx = snapshot.last_idx
response.term = lib.raft_get_current_term(self.raft)
response.first_idx = response.current_idx
self.network.enqueue_msg(response, self, other)
node_id = lib.raft_get_nodeid(self.raft)
# set membership configuration according to snapshot
for member in snapshot.members:
if -1 == member.id:
continue
node = lib.raft_get_node(self.raft, member.id)
if not node:
udata = ffi.NULL
try:
node_sv = self.network.id2server(member.id)
udata = node_sv.udata
except ServerDoesNotExist:
pass
node = lib.raft_add_node(self.raft, udata, member.id, member.id == node_id)
lib.raft_node_set_active(node, 1)
if member.voting and not lib.raft_node_is_voting(node):
lib.raft_node_set_voting(node, 1)
elif not member.voting and lib.raft_node_is_voting(node):
lib.raft_node_set_voting(node, 0)
if node_id != member.id:
assert node
# TODO: this is quite ugly
# we should have a function that removes all nodes by ourself
# if (!raft_get_my_node(self->raft)) */
# raft_add_non_voting_node(self->raft, NULL, node_id, 1); */
e = lib.raft_end_load_snapshot(self.raft)
assert(0 == e)
assert(lib.raft_get_log_count(self.raft) == 0)
self.do_membership_snapshot()
self.snapshot.image = dict(snapshot.image)
self.snapshot.last_term = snapshot.last_term
self.snapshot.last_idx = snapshot.last_idx
assert(lib.raft_get_my_node(self.raft))
# assert(sv->snapshot_fsm);
self.fsm_dict = dict(snapshot.image)
logging.warning('{} loaded snapshot t:{} idx:{}'.format(
self, snapshot.last_term, snapshot.last_idx))