Implement simplified Raft consensus for agent coordination:
Raft Basics:
- Leader election for coordination
- Log replication for consistency
- Safety: committed entries are durable
States:
- Follower: Passive, responds to requests
- Candidate: Seeking votes for election
- Leader: Handles all client requests
Methods:
request_vote(term, candidate_id, ...): Vote for candidate- Grant vote if term >= current and log is up-to-date
append_entries(...): Replicate log/heartbeatstart_election(): Become candidate, request votesbecome_leader(): Transition to leaderreplicate_log(entry): Send to followersis_consensus_reached(responses): Majority?
Log Entry:
{'term': ..., 'index': ..., 'command': ...}
Majority:
len(acceptances) > len(all_nodes) / 2
Examples
Example 1:
Input:
cp = ConsensusProtocol('node1', ['node1', 'node2', 'node3']); cp.stateOutput:
'follower'Explanation: Initial state is follower
Starter Code
class ConsensusProtocol:
"""
Raft-inspired consensus protocol for distributed agent coordination.
"""
def __init__(self, node_id, peers):
self.node_id = node_id
self.peers = peers
self.state = 'follower' # follower, candidate, leader
self.current_term = 0
self.voted_for = None
self.log = []
self.commit_index = 0
self.last_applied = 0
def request_vote(self, term, candidate_id, last_log_index, last_log_term):
"""Handle vote request from candidate"""
# Your implementation here
pass
def append_entries(self, term, leader_id, prev_log_index, prev_log_term, entries, leader_commit):
"""Handle heartbeat/log replication from leader"""
# Your implementation here
pass
def start_election(self):
"""Transition to candidate and start election"""
# Your implementation here
pass
def become_leader(self):
"""Transition to leader state"""
# Your implementation here
pass
def replicate_log(self, entry):
"""Leader replicates entry to followers"""
# Your implementation here
pass
def is_consensus_reached(self, responses):
"""Check if majority accepted"""
# Your implementation here
passPython3
ReadyLines: 1Characters: 0
Ready