hraft

hraft is a reference implementation of Hashicorp Raft implementation. The storage backend is Buntdb.

Reading and writing keys

The reference implementation is a very simple in-memory key-value store. You can set a key by sending a request to the HTTP bind address (which defaults to localhost:8080):

curl -XPOST localhost:8080/key -d '{"foo": "bar"}'

You can read the value for a key like so:

curl -XGET localhost:8080/key/foo

Running hraft

Starting and running a hraft cluster is easy. Download hraft like so:

git clone https://github.com/arriqaaq/hraft.git
cd hraft/
go build

Run your first hraft node like so:

./hraft -id node0 ~/node0

You can now set a key and read its value back:

curl -XPOST localhost:8080/key -d '{"user1": "aly"}'
curl -XGET localhost:8080/key/user1

Bring up a cluster

Bring up three terminals

Terminal 1

You should start the first node like so:

./hraft -id node1 -haddr 127.0.0.1:8080 -raddr 127.0.0.1:9000 ~/node1

This way the node is listening on an address reachable from the other nodes. This node will start up and become leader of a single-node cluster.

Terminal 2

Next, start the second node as follows:

./hraft -id node2 -haddr 127.0.0.1:8081 -raddr 127.0.0.1:9001 -join 127.0.0.1:8080 ~/node2

Terminal 3

Finally, start the third node as follows:

./hraft -id node2 -haddr 127.0.0.1:8082 -raddr 127.0.0.1:9002 -join 127.0.0.1:8080 ~/node3

This tells each new node to join the existing node. Once joined, each node now knows about the key:

curl -XGET localhost:8080/key/user1
curl -XGET localhost:8081/key/user1
curl -XGET localhost:8082/key/user1

Furthermore you can add a second key:

curl -XPOST localhost:8080/key -d '{"user2": "bloom"}'

Confirm that the new key has been set like so:

curl -XGET localhost:8080/key/user2
curl -XGET localhost:8081/key/user2
curl -XGET localhost:8082/key/user2