gistfile1.hrl

-module(session_deref).
-compile(export_all).

run() ->
    {ok, FP} = file:open("/tmp/session_mapping.txt", [write]),
    {ok, R} = riak_ring_manager:get_my_ring(),
    VNodes = riak_ring:my_indices(R),
    fold_vnodes(VNodes, FP).

fold_vnodes([], FP) ->
    file:close(FP);
fold_vnodes([VNode|T], FP) ->
    gen_server2:call(riak_vnode_master, 
                     {fold, {VNode, fun folder/3, {FP, 0}}},
                     infinity),
    fold_vnodes(T, FP).

folder({<<"session">>,K}, V, {FP, Count}) ->
    Obj = binary_to_term(V),
    Data = hd(riak_object:get_values(Obj)),
    {struct, JSON} = mochijson2:decode(Data),
    UserName = proplists:get_value(<<"username">>, JSON),
    file:write(FP, [UserName, "\n"]),
    {FP, Count};
folder({_,_K}, _V, {FP, Count}) ->
    {FP, Count}.