From 4997ac36497070e00aeb48a83c197069c8f41dc2 Mon Sep 17 00:00:00 2001
From: Siraaj Khandkar <siraaj@khandkar.net>
Date: Wed, 19 Aug 2015 17:23:18 -0400
Subject: [PATCH] Add produce method to force production on-demand.

To help with testing.
---
 src/beam_stats_producer.erl | 31 +++++++++++++++++++++++++------
 1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/src/beam_stats_producer.erl b/src/beam_stats_producer.erl
index 5c47951..cd0933c 100644
--- a/src/beam_stats_producer.erl
+++ b/src/beam_stats_producer.erl
@@ -9,6 +9,9 @@
     [ start_link/0
     ,   subscribe/1
     , unsubscribe/1
+
+    % Force production and distribution. Blocks. Mainly for testing.
+    , force_production/0
     ]).
 
 %% gen_server callbacks
@@ -26,11 +29,15 @@
 %% ============================================================================
 
 -define(SIGNAL_PRODUCTION , beam_stats_production_signal).
+-define(FORCE_PRODUCTION  , beam_stats_force_production).
 
 -record(state,
     { consumers = ordsets:new() :: ordsets:ordset(pid())
     }).
 
+-type state() ::
+    #state{}.
+
 %% ============================================================================
 %%  API
 %% ============================================================================
@@ -48,13 +55,15 @@ subscribe(PID) ->
 unsubscribe(PID) ->
     gen_server:cast(?MODULE, {unsubscribe, PID}).
 
+-spec force_production() ->
+    {}.
+force_production() ->
+    gen_server:call(?MODULE, ?FORCE_PRODUCTION).
+
 %% ============================================================================
 %%  gen_server callbacks (unused)
 %% ============================================================================
 
-handle_call(_Request, _From, State) ->
-    ?METHOD_SHOULD_NOT_BE_USED(handle_call, State).
-
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
@@ -78,9 +87,12 @@ handle_cast({unsubscribe, PID}, #state{consumers=Consumers1}=State) ->
     Consumers2 = ordsets:del_element(PID, Consumers1),
     {noreply, State#state{consumers=Consumers2}}.
 
-handle_info(?SIGNAL_PRODUCTION, #state{consumers=ConsumersSet}=State) ->
-    ConsumersList = ordsets:to_list(ConsumersSet),
-    ok = collect_and_push_to_consumers(ConsumersList),
+handle_call(?FORCE_PRODUCTION, _From, State) ->
+    {} = produce(State),
+    {reply, {}, State}.
+
+handle_info(?SIGNAL_PRODUCTION, #state{}=State) ->
+    {} = produce(State),
     ok = schedule_next_production(),
     {noreply, State}.
 
@@ -88,6 +100,13 @@ handle_info(?SIGNAL_PRODUCTION, #state{consumers=ConsumersSet}=State) ->
 %%  Private
 %% ============================================================================
 
+-spec produce(state()) ->
+    {}.
+produce(#state{consumers=ConsumersSet}) ->
+    ConsumersList = ordsets:to_list(ConsumersSet),
+    ok = collect_and_push_to_consumers(ConsumersList),
+    {}.
+
 -spec schedule_first_production() ->
     ok.
 schedule_first_production() ->
-- 
2.20.1