README.md

lbm_pg

Another approach to process groups. lbm_pg offers a process group implementation similar to pg2 without the use of global with integrated facilities to (reliably) send messages to group members with failover, timeouts, member caching and more.

Since group names can be arbitrary terms, lbm_pg can also act as a simple process registry. The distribution backend is similar to pg2 and thus has the same robustness, e.g. when it comes to netsplits. Every process implementing either the gen_server or gen_fsm behaviour can be joined into a group.

More Information

For more information look at the comprehensive inline EDoc documentation.

Dependencies

lbm_pg uses worker_pool to pool worker processes for asynchronous sends. Don't be afraid, the dependencies of the worker_pool project itself are test only. This means you don't have to include them in your release.

Example

Join a gen_server into the 1337 group:

init([]) ->
        lbm_pg:join_server(1337),
        {ok, #state{}}.

Handle group messages in the gen_server:

handle_call(the_group_message, _From, State) ->
        {reply, the_answer, State}.

Send a message to a group member from an arbitrary process:

TheAnswer = lbm_pg:sync_send(1337, the_group_message).

Send an asynchronous message to a group member with error feedback:

ok = lbm_pg:send(1337, the_group_message, 100, [error_feedback]),
%% NOTE: This is a bad example for error handling
receive
        ?LBM_PG_ERROR(1337, the_group_message, Reason) -> {error, Reason}
after 1000 ->
        ok
end.