def test_peer_rejects_append_entries_on_term_mismatch_setup():
event_queues = common.create_event_queues()
peers = None
startup_state = "follower"
initial_term = 3
election_timeout = range(1000, 3000)
commit_index = 0
log = MemoryLog()
log.append(LogEntry(log_index=1, term=2, command=None, data=None))
log.append(LogEntry(log_index=2, term=2, command=None, data=None))
log.append(LogEntry(log_index=3, term=2, command=None, data=None))
log.append(LogEntry(log_index=4, term=2, command=None, data=None))
key_store = None
initialize_next_index = False
event_queues.state_machine.put_nowait(
AppendEntries(
event_id=str(uuid.uuid4()),
source_server="leader_server",
destination_server="peer_server",
term=4,
leader_id="leader_server",
prev_log_index=4,
prev_log_term=4,
entries=[LogEntry(log_index=5, term=4, command=None, data=None)],
leader_commit=1,
))
proc = mp.Process(
target=common.start_state_machine,
args=(
event_queues,
startup_state,
peers,
initial_term,
election_timeout,
commit_index,
log,
key_store,
initialize_next_index,
"peer_server",
),
)
proc.start()
time.sleep(0.1)
yield event_queues
proc.kill()
def test_peer_grants_vote_setup():
event_queues = common.create_event_queues()
peers = None
startup_state = "follower"
initial_term = 3
election_timeout = range(1000, 3000)
commit_index = 0
log = MemoryLog()
log.append(LogEntry(log_index=1, term=3, command=None, data=None))
log.append(LogEntry(log_index=2, term=3, command=None, data=None))
key_store = None
initialize_next_index = False
event_queues.state_machine.put_nowait(
RequestVote(
event_id=str(uuid.uuid4()),
source_server="candidate_server",
destination_server="peer_server",
term=4,
candidate_id="candidate_server",
last_log_index=6,
last_log_term=3,
))
event_queues.state_machine.put_nowait(
LocalStateSnapshotRequestForTesting())
proc = mp.Process(
target=common.start_state_machine,
args=(
event_queues,
startup_state,
peers,
initial_term,
election_timeout,
commit_index,
log,
key_store,
initialize_next_index,
"peer_server",
),
)
proc.start()
time.sleep(0.1)
yield event_queues
proc.kill()
def test_peer_deletes_conflicting_log_entries_and_appends_new(
conflicting_entries):
event_queues = conflicting_entries
event = event_queues.dispatcher.get_nowait()
state = event_queues.testing.get_nowait()
assert event.success == True
assert event.term == 4
assert event.last_log_index == 5
assert state.state["log"] == [
LogEntry(log_index=1,
term=2,
command="_set",
data={
"key": "a",
"value": "foo"
}),
LogEntry(log_index=2,
term=2,
command="_set",
data={
"key": "a",
"value": "foo"
}),
LogEntry(log_index=3,
term=2,
command="_set",
data={
"key": "a",
"value": "foo"
}),
LogEntry(log_index=4,
term=2,
command="_set",
data={
"key": "a",
"value": "foo"
}),
LogEntry(log_index=5,
term=4,
command="_set",
data={
"key": "a",
"value": 1
}),
]
def _handle_client_request(self, event):
log_entry = LogEntry(log_index=self._log.next_index(),
term=self._term,
command=event.command,
data=event.data)
self._log.append(log_entry)
self._event_queues.log_writer.put_nowait(log_entry)
self._pending_client_requests.append(
PendingClientRequest(
request_id=event.event_id,
request_commit_index=log_entry.log_index,
request_receive_time=time.monotonic(),
))
def test_peer_commits_entries_and_advances_commit_index_setup():
event_queues = common.create_event_queues()
peers = None
startup_state = "follower"
initial_term = 2
election_timeout = range(1000, 3000)
commit_index = 0
log = MemoryLog()
log.append(
LogEntry(log_index=1,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=2,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=3,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=4,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=5,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=6,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
log.append(
LogEntry(log_index=7,
term=2,
command="_set",
data={
"key": "a",
"value": 1
}))
key_store = None
initialize_next_index = False
event_queues.state_machine.put_nowait(
AppendEntries(
event_id=str(uuid.uuid4()),
source_server="leader_server",
destination_server="peer_server",
term=3,
leader_id="leader_server",
prev_log_index=7,
prev_log_term=2,
entries=[
LogEntry(log_index=8,
term=2,
command="_set",
data={
"key": "b",
"value": 2
})
],
leader_commit=8,
))
event_queues.state_machine.put_nowait(
LocalStateSnapshotRequestForTesting())
proc = mp.Process(
target=common.start_state_machine,
args=(
event_queues,
startup_state,
peers,
initial_term,
election_timeout,
commit_index,
log,
key_store,
initialize_next_index,
"peer_server",
),
)
proc.start()
time.sleep(0.1)
yield event_queues
proc.kill()
def test_peer_appends_new_entries(new_entries):
event_queues = new_entries
event = event_queues.dispatcher.get_nowait()
state = event_queues.testing.get_nowait()
assert event.success == True
assert event.term == 3
assert event.last_log_index == 8
assert state.state["log"] == [
LogEntry(log_index=1,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=2,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=3,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=4,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=5,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=6,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=7,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
LogEntry(log_index=8,
term=2,
command="_set",
data={
"key": "a",
"value": 11
}),
]
from raft.structures.log_entry import LogEntry
_DEFAULT_LOG_INDEX = 0
_DEFAULT_LOG_TERM = 0
_DEFAULT_LOG_ENTRY = LogEntry(
log_index=_DEFAULT_LOG_INDEX,
term=_DEFAULT_LOG_TERM,
command=None,
data=None,
)
class MemoryLog:
def __init__(self):
self._log = []
def append(self, entry):
self._log.append(entry)
def at(self, index):
try:
return self._log[index] if index < 0 else self._log[index - 1]
except IndexError:
return None
def last_index(self):
if self._log:
return self._log[-1].log_index
else:
return _DEFAULT_LOG_INDEX