src/lwes_emitter.erl

   1 -module(lwes_emitter).
   2
   3 % create any resources and return a fixed structure which will be sent in
   4 % subsequent calls, configuration is expected to be a list of some sort,
   5 % most of the time this will be something like [{key, value}].
   6 -callback new(Config :: list()) -> State :: term().
   7
   8 % return an id to be used for stats gathering.  In most cases this should
   9 % be an atom so that it will show up under the label column for lwes:stats()
  10 % calls
  11 -callback id(State :: term()) ->
  12     {Ip :: tuple(), Port :: integer() }
  13   | {Label :: atom(), {Ip :: tuple(), Port :: integer() }}
  14   | atom().
  15
  16 % prepare the event, in most cases this will use one of the to_* methods
  17 % in lwes_event (like to_binary, to_iolist, to_json, etc), but also allows
  18 % one to implement any serialization format as a plugin
  19 -callback prep(Event :: term()) -> term().
  20
  21 % emit the event, this will get the State from new/1 as well as the event
  22 % from prep/1
  23 -callback emit(State :: term(), Event :: term()) -> ok | {error, atom()}.
  24
  25 % close the emitter, called on shutdown or if configuration is updated
  26 % this could be called, then immediately new/1 called again.
  27 -callback close(State :: term()) -> ok.