nikosl / pyraft

Raft experiment

pyraft

Partial implementation of the Raft consensus algorithm¹.

Not Implemented

persistence, snapshot

Run

make start_cluster

Stop

make stop_cluster

Scenarios

An up to date node should always be available. You can find the leader from the kv_client.py output. You can use docker-compose stop $peer_name to kill a leader and force a switch over with docker-compose start $peer_name you can start the peer again and let it join the cluster.

Usage

Add the pyraft package to your PYTHONPATH and execute the command from the project directory.

To read a key

env PYTHONPATH=./pyraft:$PYTHONPATH python ./pyraft/client/kv_client.py -nodes 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003 -get your_key

To add a key

env PYTHONPATH=./pyraft:$PYTHONPATH python ./pyraft/client/kv_client.py -nodes 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003 -put your_key value

To remove a key

env PYTHONPATH=./pyraft:$PYTHONPATH python ./pyraft/client/kv_client.py -nodes 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003 -del your_key 

Example

# start the cluster, you can find the leader from the output
make start_cluster

# add a new key, from a different terminal, you can find the leader id from the command output
env PYTHONPATH=./pyraft:$PYTHONPATH python ./pyraft/client/kv_client.py -nodes 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003 -put foo bar
# read the new added key
env PYTHONPATH=./pyraft:$PYTHONPATH python ./pyraft/client/kv_client.py -nodes 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003 -get foo
# kill the leader node
docker-compose stop $peer_name
# add a couple of keys and start the node again, verify your keys
docker-compose stop $peer_name

Footnotes

1. https://raft.github.io/ ↩