diff options
| -rw-r--r-- | src/rexi.erl | 38 | ||||
| -rw-r--r-- | src/rexi_server.erl | 8 |
2 files changed, 43 insertions, 3 deletions
diff --git a/src/rexi.erl b/src/rexi.erl new file mode 100644 index 00000000..745afedb --- /dev/null +++ b/src/rexi.erl @@ -0,0 +1,38 @@ +-module(rexi). +-export([start/0, stop/0, restart/0]). +-export([cast/2, cast/3]). +-export([reply/1]). + +-define(SERVER, rexi_server). + +start() -> + application:start(rexi). + +stop() -> + application:stop(rexi). + +restart() -> + stop(), start(). + +-spec cast(node(), mfa()) -> {ok, reference()}. +cast(Node, MFA) -> + cast(Node, self(), MFA). + +%% @doc Executes apply(M, F, A) on Node. +%% You might want to use this instead of rpc:cast/4 for two reasons. First, +%% the Caller pid and the returned reference are inserted into the remote +%% process' dictionary as 'rexi_from', so it has a way to communicate with you. +%% Second, the remote process is monitored. If it dies, Caller will receive a +%% message of the form `{rexi_EXIT, Ref, Reason}' where Ref is the returned +%% reference and Reason is the exit reason. +-spec cast(node(), pid(), mfa()) -> {ok, reference()}. +cast(Node, Caller, MFA) -> + Ref = make_ref(), + ok = gen_server:cast({?SERVER, Node}, {doit, {Caller,Ref}, MFA}), + {ok, Ref}. + +%% @doc convenience function to reply to the original rexi Caller. +-spec reply(any()) -> any(). +reply(Reply) -> + {Caller, Ref} = get(rexi_from), + erlang:send(Caller, {Ref,Reply}). diff --git a/src/rexi_server.erl b/src/rexi_server.erl index 65110535..e06fd86d 100644 --- a/src/rexi_server.erl +++ b/src/rexi_server.erl @@ -30,7 +30,7 @@ handle_info({'DOWN', Ref, process, _, normal}, #st{workers=Workers} = St) -> handle_info({'DOWN', Ref, process, Pid, Reason}, #st{workers=Workers} = St) -> case find_worker(Ref, Workers) of {Pid, Ref, From} -> - notify_caller(From, Pid, Reason); + notify_caller(From, Reason); false -> ok end, {noreply, St#st{workers = remove_worker(Ref, Workers)}}; @@ -44,6 +44,8 @@ terminate(_Reason, St) -> code_change(_OldVsn, St, _Extra) -> {ok, St}. +%% @doc initializes a process started by rexi_server. +-spec init_p({pid(),reference()}, mfa()) -> any(). init_p(From, {M,F,A}) -> put(rexi_from, From), try apply(M, F, A) catch _:Reason -> exit(Reason) end. @@ -59,5 +61,5 @@ remove_worker(Ref, List) -> find_worker(Ref, List) -> lists:keyfind(Ref, 2, List). -notify_caller({Caller, CallerRef}, Pid, Reason) -> - Caller ! {worker_died, CallerRef, Pid, Reason}. +notify_caller({Caller, Ref}, Reason) -> + erlang:send(Caller, {rexi_EXIT, Ref, Reason}). |