Orestes

Simple implementation of a distributed key-value server, aimed to learn basic concepts of functional programming through Haskell. For the distribution it uses cloud-haskell libraries, based on asynchronous message protocol like Erlang distribution actor model. It works on both a cluster of machines or on a single one according to a master-slave topology. It currently support just the common operations PUT, GET and DEL and it lacks a suitable communication protocol, on the other side it is perfectly usable by using a generic TCP client like Telnet or Netcat issuing commands as strings.

Quickstart

$ stack build

Run

$ stack run <args>

It can be started either on a single node or distributed in a cluster of machines

Single machine

$ stack run <port>

<port> argument is optional and it fallback to 6373 if omitted.

Cluster

Orestes is designed as Master-slave topology, in order to start a cluster, it is first needed to start all slave nodes

$ stack run slave <ip-address> <backend-port>

and finally the master node, which will discover all his slaves

$ stack run master <ip-address> <backend-port> <port>

Backend port is needed to communicate between nodes, again port fallback to 6373 if not set.

It currently can be tested using a generic TCP client like Telnet or Netcat, just connect and issue commands.

$ nc 127.0.0.1 6373
put key value
OK
get key
value

License

See the LICENSE file for license rights and limitations (MIT).