Merge pull request #728 from filecoin-project/fix/events-double-trigger

fix events double trigger issue

chain/events/events.go

@@ -24,6 +24,7 @@ type RevertHandler func(ctx context.Context, ts *types.TipSet) error
 
 type heightHandler struct {
 	confidence int
+	called     bool
 
 	handle HeightHandler
 	revert RevertHandler

chain/events/events_called.go

@@ -183,6 +183,10 @@ func (e *calledEvents) applyWithConfidence(ts *types.TipSet) {
 		}
 
 		for _, event := range events {
+			if event.called {
+				continue
+			}
+
 			trigger := e.triggers[event.trigger]
 			if trigger.disabled {
 				continue

chain/events/events_height.go

@@ -40,6 +40,7 @@ func (e *heightEvents) headChangeAt(rev, app []*types.TipSet) error {
 				ctx, span := trace.StartSpan(ctx, "events.HeightRevert")
 
 				err := e.heightTriggers[tid].revert(ctx, ts)
+				e.heightTriggers[tid].called = false
 
 				span.End()
 
@@ -82,6 +83,11 @@ func (e *heightEvents) headChangeAt(rev, app []*types.TipSet) error {
 		apply := func(h uint64, ts *types.TipSet) error {
 			for _, tid := range e.htTriggerHeights[h] {
 				hnd := e.heightTriggers[tid]
+				if hnd.called {
+					return nil
+				}
+				hnd.called = true
+
 				triggerH := h - uint64(hnd.confidence)
 
 				incTs, err := e.tsc.getNonNull(triggerH)

chain/events/events_test.go

@@ -258,6 +258,48 @@ func TestAt(t *testing.T) {
 	require.Equal(t, false, reverted)
 }
 
+func TestAtDoubleTrigger(t *testing.T) {
+	fcs := &fakeCS{
+		t:   t,
+		h:   1,
+		tsc: newTSCache(2*build.ForkLengthThreshold, nil),
+	}
+	require.NoError(t, fcs.tsc.add(makeTs(t, 1, dummyCid)))
+
+	events := NewEvents(context.Background(), fcs)
+
+	var applied bool
+	var reverted bool
+
+	err := events.ChainAt(func(_ context.Context, ts *types.TipSet, curH uint64) error {
+		require.Equal(t, 5, int(ts.Height()))
+		require.Equal(t, 8, int(curH))
+		applied = true
+		return nil
+	}, func(_ context.Context, ts *types.TipSet) error {
+		reverted = true
+		return nil
+	}, 3, 5)
+	require.NoError(t, err)
+
+	fcs.advance(0, 6, nil)
+	require.False(t, applied)
+	require.False(t, reverted)
+
+	fcs.advance(0, 1, nil)
+	require.True(t, applied)
+	require.False(t, reverted)
+	applied = false
+
+	fcs.advance(2, 2, nil)
+	require.False(t, applied)
+	require.False(t, reverted)
+
+	fcs.advance(4, 4, nil)
+	require.True(t, applied)
+	require.True(t, reverted)
+}
+
 func TestAtNullTrigger(t *testing.T) {
 	fcs := &fakeCS{
 		t:   t,
@@ -562,6 +604,12 @@ func TestCalled(t *testing.T) {
 	require.Equal(t, false, reverted)
 	applied = false
 
+	// dip below confidence
+	fcs.advance(2, 2, nil) // H=10 (confidence=3, apply)
+
+	require.Equal(t, false, applied)
+	require.Equal(t, false, reverted)
+
 	require.Equal(t, uint64(7), appliedTs.Height())
 	require.Equal(t, "bafkqaaa", appliedTs.Blocks()[0].Messages.String())
 	require.Equal(t, uint64(10), appliedH)