README.md

An Erlang implementation of kademlia

To run all tests and download all dependecies:

$ rebar3 eunit --module=peer,kbucket,it

Warning: some tests may fail since there are some sleep() to wait until some procedures end. This is a known issue and will be addressed in future developments, try to run several times all tests.

Setting up a little network

$ rebar3 as test shell

1> K = 20. % Kademlia K parameter
20
2> Alpha = 3. % Kademlia Alpha parameter
3
3> A = peer:start(123, K, Alpha).
{<0.193.0>,123}
4> B = peer:start(100, K, Alpha).
{<0.199.0>,100}
5> C = peer:start(50, K, Alpha).
{<0.204.0>,50}
6>
6> peer:join(A, B).
....
7> peer:join(B, C).
....
8> peer:iterative_store(A, {mykey, "a value string"}).
....
ok.
9> Value = peer:iterative_find_value(C, mykey).
....
10> Value.
"a value string".
11> peer:iterative_store(B, {mylist, [1, 2, 3]}).
....
ok.
12> List = peer:iterative_find_value(A, mylist).
....
11> List.
[1, 2, 3]

For each message will be created a log. By default the logs are displayed on the console, to modify this behaviour check out sys.config file and comment out what you do not want:

[
  {'kademlia', []},
  {lager, [
    {handlers, [
        {lager_logstash_backend, [
               {level, info},
               {output, {tcp, "localhost", 9125}},
               {format, json},
               {json_encoder, jsx}
        ]},
        {lager_console_backend, error},
        {lager_console_backend, info}
%%        {lager_file_backend, [{file, "log/error.log"}, {level, error}]},
%%        {lager_file_backend, [{file, "log/consoles.log"}, {level, info}]}
    ]}
   ]}
].

All the logs are sent to the local port 9125, waiting to be consumed by a logstash daemon. The project provides vagrant-elk-box, an already configured vagrant-box to display the logs through an ELK stack.