From 3f6796fba413cca7f2ea9a7e03d7965e7eda7378 Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Tue, 6 Aug 2024 09:36:14 +0000
Subject: [PATCH] fix(baseapp): return events from preblocker in
 FinalizeBlockResponse (backport #21159) (#21162)

Co-authored-by: Facundo Medica <14063057+facundomedica@users.noreply.github.com>
Co-authored-by: marbar3778 <marbar3778@yahoo.com>
Co-authored-by: Facundo <facundomedica@gmail.com>
---
 CHANGELOG.md         |  1 +
 baseapp/abci.go      |  5 ++++-
 baseapp/abci_test.go | 12 +++++++-----
 baseapp/baseapp.go   |  8 +++++---
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e48783a88e8b..054d327fe8a9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -40,6 +40,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## Bug Fixes
 
+* (baseapp) [#21159](https://github.com/cosmos/cosmos-sdk/pull/21159) Return PreBlocker events in FinalizeBlockResponse.
 * [#20939](https://github.com/cosmos/cosmos-sdk/pull/20939) Fix collection reverse iterator to include `pagination.key` in the result.
 * (client/grpc) [#20969](https://github.com/cosmos/cosmos-sdk/pull/20969) Fix `node.NewQueryServer` method not setting `cfg`.
 * (testutil/integration) [#21006](https://github.com/cosmos/cosmos-sdk/pull/21006) Fix `NewIntegrationApp` method not writing default genesis to state
diff --git a/baseapp/abci.go b/baseapp/abci.go
index 2bef4642ba41..edfab76ef0c3 100644
--- a/baseapp/abci.go
+++ b/baseapp/abci.go
@@ -753,10 +753,13 @@ func (app *BaseApp) internalFinalizeBlock(ctx context.Context, req *abci.Request
 			WithHeaderHash(req.Hash))
 	}
 
-	if err := app.preBlock(req); err != nil {
+	preblockEvents, err := app.preBlock(req)
+	if err != nil {
 		return nil, err
 	}
 
+	events = append(events, preblockEvents...)
+
 	beginBlock, err := app.beginBlock(req)
 	if err != nil {
 		return nil, err
diff --git a/baseapp/abci_test.go b/baseapp/abci_test.go
index 2c250b03ddf9..3c67385dfa67 100644
--- a/baseapp/abci_test.go
+++ b/baseapp/abci_test.go
@@ -2029,22 +2029,24 @@ func TestBaseApp_PreBlocker(t *testing.T) {
 	wasHookCalled := false
 	app.SetPreBlocker(func(ctx sdk.Context, req *abci.RequestFinalizeBlock) (*sdk.ResponsePreBlock, error) {
 		wasHookCalled = true
-		return &sdk.ResponsePreBlock{
-			ConsensusParamsChanged: true,
-		}, nil
+
+		ctx.EventManager().EmitEvent(sdk.NewEvent("preblockertest", sdk.NewAttribute("height", fmt.Sprintf("%d", req.Height))))
+		return &sdk.ResponsePreBlock{ConsensusParamsChanged: false}, nil
 	})
 	app.Seal()
 
-	_, err = app.FinalizeBlock(&abci.RequestFinalizeBlock{Height: 1})
+	res, err := app.FinalizeBlock(&abci.RequestFinalizeBlock{Height: 1})
 	require.NoError(t, err)
 	require.Equal(t, true, wasHookCalled)
+	require.Len(t, res.Events, 1)
+	require.Equal(t, "preblockertest", res.Events[0].Type)
 
 	// Now try erroring
 	app = baseapp.NewBaseApp(name, logger, db, nil)
 	_, err = app.InitChain(&abci.RequestInitChain{})
 	require.NoError(t, err)
 
-	app.SetPreBlocker(func(ctx sdk.Context, req *abci.RequestFinalizeBlock) (*sdk.ResponsePreBlock, error) {
+	app.SetPreBlocker(func(_ sdk.Context, req *abci.RequestFinalizeBlock) (*sdk.ResponsePreBlock, error) {
 		return nil, errors.New("some error")
 	})
 	app.Seal()
diff --git a/baseapp/baseapp.go b/baseapp/baseapp.go
index a89b48bcbafc..a89620485087 100644
--- a/baseapp/baseapp.go
+++ b/baseapp/baseapp.go
@@ -704,12 +704,13 @@ func (app *BaseApp) cacheTxContext(ctx sdk.Context, txBytes []byte) (sdk.Context
 	return ctx.WithMultiStore(msCache), msCache
 }
 
-func (app *BaseApp) preBlock(req *abci.RequestFinalizeBlock) error {
+func (app *BaseApp) preBlock(req *abci.RequestFinalizeBlock) ([]abci.Event, error) {
+	var events []abci.Event
 	if app.preBlocker != nil {
 		ctx := app.finalizeBlockState.Context()
 		rsp, err := app.preBlocker(ctx, req)
 		if err != nil {
-			return err
+			return nil, err
 		}
 		// rsp.ConsensusParamsChanged is true from preBlocker means ConsensusParams in store get changed
 		// write the consensus parameters in store to context
@@ -720,8 +721,9 @@ func (app *BaseApp) preBlock(req *abci.RequestFinalizeBlock) error {
 			ctx = ctx.WithBlockGasMeter(gasMeter)
 			app.finalizeBlockState.SetContext(ctx)
 		}
+		events = ctx.EventManager().ABCIEvents()
 	}
-	return nil
+	return events, nil
 }
 
 func (app *BaseApp) beginBlock(_ *abci.RequestFinalizeBlock) (sdk.BeginBlock, error) {