feat(core): add dispatch/1 to aggregate to entirely hide gen_server

ccamel · ccamel · commit f3a39ccd6bbe · 2025-03-25T15:31:27.000+01:00
diff --git a/apps/event_sourcing_core/src/event_sourcing_core_gen_aggregate.erl b/apps/event_sourcing_core/src/event_sourcing_core_gen_aggregate.erl
@@ -3,9 +3,10 @@
 -behaviour(gen_server).
 
 -export([start_link/3, start_link/4, handle_info/2, init/1, handle_call/3, handle_cast/2,
-         code_change/3, terminate/2]).
+         code_change/3, terminate/2, dispatch/2]).
 
--export_type([command/0, aggregate_state/0, stream_id/0, state/0, sequence/0, timestamp/0]).
+-export_type([command/0, aggregate_state/0, stream_id/0, state/0, sequence/0,
+              timestamp/0]).
 
 -define(SEQUENCE_ZERO, 0).
 -define(INACTIVITY_TIMEOUT, 5000).
@@ -72,6 +73,14 @@ start_link(Aggregate, Store, Id, Opts) ->
 start_link(Aggregate, Store, Id) ->
     start_link(Aggregate, Store, Id, #{}).
 
+-spec dispatch(Pid, Command) -> {ok, Result} | {error, Reason}
+    when Pid :: pid(),
+         Command :: command(),
+         Result :: term(),
+         Reason :: term().
+dispatch(Pid, Command) ->
+    gen_server:call(Pid, Command).
+
 -record(state,
         {aggregate :: module(),
          store :: module(),
diff --git a/apps/event_sourcing_core/test/event_sourcing_core_gen_aggregate_tests.erl b/apps/event_sourcing_core/test/event_sourcing_core_gen_aggregate_tests.erl
@@ -38,20 +38,20 @@ aggregate_behaviour() ->
 
     ?assertState(Pid, Id, #{balance := 0}, 0),
 
-    ?assertEqual(ok, gen_server:call(Pid, {deposit, 100})),
+    ?assertEqual(ok, event_sourcing_core_gen_aggregate:dispatch(Pid, {deposit, 100})),
     ?assertState(Pid, Id, #{balance := 100}, 1),
 
-    ?assertEqual(ok, gen_server:call(Pid, {deposit, 100})),
+    ?assertEqual(ok, event_sourcing_core_gen_aggregate:dispatch(Pid, {deposit, 100})),
     ?assertState(Pid, Id, #{balance := 200}, 2),
 
-    ?assertEqual(ok, gen_server:call(Pid, {withdraw, 50})),
+    ?assertEqual(ok, event_sourcing_core_gen_aggregate:dispatch(Pid, {withdraw, 50})),
     ?assertState(Pid, Id, #{balance := 150}, 3).
 
 aggregate_passivation() ->
     {Id, Pid} = start_test_account(1000),
 
-    ?assertEqual(ok, gen_server:call(Pid, {deposit, 100})),
-    ?assertEqual(ok, gen_server:call(Pid, {withdraw, 25})),
+    ?assertEqual(ok, event_sourcing_core_gen_aggregate:dispatch(Pid, {deposit, 100})),
+    ?assertEqual(ok, event_sourcing_core_gen_aggregate:dispatch(Pid, {withdraw, 25})),
 
     ?assertState(Pid, Id, #{balance := 75}, 2),
 
@@ -68,8 +68,10 @@ aggregate_passivation() ->
 aggregate_invalid_command() ->
     {_, Pid} = start_test_account(5000),
 
-    ?assertEqual({error, invalid_command}, gen_server:call(Pid, invalid)),
-    ?assertEqual({error, insufficient_funds}, gen_server:call(Pid, {withdraw, 100})).
+    ?assertEqual({error, invalid_command},
+                 event_sourcing_core_gen_aggregate:dispatch(Pid, invalid)),
+    ?assertEqual({error, insufficient_funds},
+                 event_sourcing_core_gen_aggregate:dispatch(Pid, {withdraw, 100})).
 
 start_test_account(Timeout) ->
     Id = "bank-account-123",
