enats

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-module(nats_service).

-export([serve/2, reply/2, reply/3]).
-ignore_xref([serve/2, reply/2, reply/3]).

%%%===================================================================
%%% API
%%%===================================================================

serve(Conn, #{name := _, version := _,
              module := Module, state := State, endpoints := Endpoints} = Svc) ->
    Exports = try
                  sets:from_list(Module:module_info(exports), [{version, 2}])
              catch _:_ -> erlang:error(badarg, [Svc]) end,
    SvcEndpoints =
        lists:map(
          fun(#{name := _, function := Function} = EndP) ->
                  case sets:is_element({Function, 6}, Exports) of
                      true -> ok;
                      false -> erlang:error(badarg, [EndP])
                  end,
                  nats:endpoint(
                    maps:with([name, group_name, queue_group, metadata], EndP), Function);
             (EndP) ->
                  erlang:error(badarg, [EndP])
          end, Endpoints),
    Service =
        nats:service(
          maps:with([name, version, description, metadata], Svc), SvcEndpoints, Module, State),
    nats:serve(Conn, Service).

reply(Key, Payload) ->
    nats:service_reply(Key, Payload).

reply(Key, Header, Payload) ->
    nats:service_reply(Key, Header, Payload).