Fix ff_transfer_machine actions (#18)

apps/ff_transfer/src/ff_deposit.erl

@@ -126,9 +126,9 @@ events(ID, Range) ->
 %% ff_transfer_machine behaviour
 
 -spec process_transfer(deposit()) ->
-    {ok, [ff_transfer_machine:event(ff_transfer:event())]} |
+    {ok, {ff_transfer_machine:action(), [ff_transfer_machine:event(ff_transfer:event())]}} |
     {error, _Reason}.
 process_transfer(#{status := pending, p_transfer := #{status := prepared}}) ->
-    {ok, [{status_changed, succeeded}]};
+    {ok, {continue, [{status_changed, succeeded}]}};
 process_transfer(Transfer) ->
     ff_transfer:process_transfer(Transfer).

apps/ff_transfer/src/ff_transfer.erl

@@ -118,7 +118,7 @@ construct_p_transfer_id(ID) ->
 %% ff_transfer_machine behaviour
 
 -spec process_transfer(transfer(_)) ->
-    {ok, [ff_transfer_machine:event(event())] | poll} |
+    {ok, {ff_transfer_machine:action(), [ff_transfer_machine:event(event())]}} |
     {error, _Reason}.
 
 process_transfer(Transfer) ->
@@ -142,13 +142,19 @@ deduce_activity(_) ->
     undefined.
 
 process_activity(prepare_transfer, Transfer) ->
-    with(p_transfer, Transfer, fun ff_postings_transfer:prepare/1);
+    do(fun () ->
+        {continue, unwrap(with(p_transfer, Transfer, fun ff_postings_transfer:prepare/1))}
+    end);
 
 process_activity(commit_transfer, Transfer) ->
-    with(p_transfer, Transfer, fun ff_postings_transfer:commit/1);
+    do(fun () ->
+        {undefined, unwrap(with(p_transfer, Transfer, fun ff_postings_transfer:commit/1))}
+    end);
 
 process_activity(cancel_transfer, Transfer) ->
-    with(p_transfer, Transfer, fun ff_postings_transfer:cancel/1).
+    do(fun () ->
+        {undefined, unwrap(with(p_transfer, Transfer, fun ff_postings_transfer:cancel/1))}
+    end).
 
 %%
 

apps/ff_transfer/src/ff_transfer_machine.erl

@@ -17,19 +17,21 @@
 %% Behaviour definition
 
 -type st(T)    :: ff_machine:st(transfer(T)).
+-type action() :: poll | continue | undefined.
 
 -export_type([id/0]).
 -export_type([ns/0]).
+-export_type([action/0]).
 -export_type([st/1]).
 -export_type([event/1]).
 -export_type([events/1]).
 
 -callback process_transfer(transfer(_)) ->
-    {ok, [event(_)] | poll} |
+    {ok, {action(), [event(_)]}} |
     {error, _Reason}.
 
 -callback process_call(_CallArgs, transfer(_)) ->
-    {ok, [event(_)] | poll} |
+    {ok, {action(), [event(_)]}} |
     {error, _Reason}.
 
 -optional_callbacks([process_call/2]).
@@ -142,21 +144,26 @@ process_call(CallArgs, Machine, _, _Opts) ->
     Transfer = transfer(St),
     {ok, process_result((ff_transfer:handler(Transfer)):process_call(CallArgs, Transfer), St)}.
 
-process_result({ok, poll}, St) ->
-    #{
-        action => set_poll_timer(St)
-    };
-process_result({ok, Events}, _St) ->
-    #{
-        events => ff_machine:emit_events(Events),
-        action => continue
-    };
+process_result({ok, {Action, Events}}, St) ->
+    genlib_map:compact(#{
+        events => set_events(Events),
+        action => set_action(Action, St)
+    });
 process_result({error, Reason}, _St) ->
     #{
         events => emit_failure(Reason)
     }.
 
-set_poll_timer(St) ->
+set_events([]) ->
+    undefined;
+set_events(Events) ->
+    ff_machine:emit_events(Events).
+
+set_action(continue, _St) ->
+    continue;
+set_action(undefined, _St) ->
+    undefined;
+set_action(poll, St) ->
     Now = machinery_time:now(),
     Timeout = erlang:max(1, machinery_time:interval(Now, ff_machine:updated(St)) div 1000),
     {set_timer, {timeout, Timeout}}.

apps/ff_transfer/src/ff_withdrawal.erl

@@ -130,7 +130,7 @@ events(ID, Range) ->
 %% ff_transfer_machine behaviour
 
 -spec process_transfer(withdrawal()) ->
-    {ok, [ff_transfer_machine:event(ff_transfer:event())]} |
+    {ok, {ff_transfer_machine:action(), [ff_transfer_machine:event(ff_transfer:event())]}} |
     {error, _Reason}.
 
 process_transfer(Transfer = #{status := pending, session := _}) ->
@@ -152,7 +152,7 @@ create_session(Withdrawal) ->
     },
     do(fun () ->
         ok = unwrap(ff_withdrawal_session_machine:create(ID, TransferData, #{destination => destination(Withdrawal)})),
-        [{session_started, ID}]
+        {continue, [{session_started, ID}]}
     end).
 
 construct_session_id(ID) ->
@@ -163,16 +163,16 @@ poll_session_completion(#{session := SID}) ->
     do(fun () ->
         case ff_withdrawal_session_machine:status(Session) of
             active ->
-                poll;
+                {poll, []};
             {finished, {success, _}} ->
-                [
+                {continue, [
                     {session_finished, SID},
                     {status_changed, succeeded}
-                ];
+                ]};
             {finished, {failed, Failure}} ->
-                [
+                {continue, [
                     {session_finished, SID},
                     {status_changed, {failed, Failure}}
-                ]
+                ]}
         end
     end).