fix: state listener could observe discarded writes (#13459)

* fix: state listener could observe uncommitted writes Closes: #13457 don't pass listeners to nested cached store, only the most inner layer's cache writes should be observed. * Update CHANGELOG.md * add unit test * rename Co-authored-by: Marko <[email protected]>
cosmos · Oct 6, 2022 · bb54c59 · bb54c59
1 parent 90bd316
commit bb54c59
Show file tree

Hide file tree

Showing 3 changed files with 55 additions and 1 deletion.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -166,6 +166,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/gov) [#13051](https://github.com/cosmos/cosmos-sdk/pull/13051) In SubmitPropsal, when a legacy msg fails it's handler call, wrap the error as ErrInvalidProposalContent (instead of ErrNoProposalHandlerExists).
 * (x/gov) [#13045](https://github.com/cosmos/cosmos-sdk/pull/13045) Fix gov migrations for v3(0.46).
 * (snapshot) [#13400](https://github.com/cosmos/cosmos-sdk/pull/13400) Fix snapshot checksum issue in golang 1.19.
+* (store) [#13459](https://github.com/cosmos/cosmos-sdk/pull/13459) Don't let state listener observe the uncommitted writes.
 
 ### Deprecated
 

diff --git a/store/cachemulti/store.go b/store/cachemulti/store.go
@@ -45,6 +45,9 @@ func NewFromKVStore(
 	keys map[string]types.StoreKey, traceWriter io.Writer, traceContext types.TraceContext,
 	listeners map[types.StoreKey][]types.WriteListener,
 ) Store {
+	if listeners == nil {
+		listeners = make(map[types.StoreKey][]types.WriteListener)
+	}
 	cms := Store{
 		db:           cachekv.NewStore(store),
 		stores:       make(map[types.StoreKey]types.CacheWrap, len(stores)),
@@ -86,7 +89,8 @@ func newCacheMultiStoreFromCMS(cms Store) Store {
 		stores[k] = v
 	}
 
-	return NewFromKVStore(cms.db, stores, nil, cms.traceWriter, cms.traceContext, cms.listeners)
+	// don't pass listeners to nested cache store.
+	return NewFromKVStore(cms.db, stores, nil, cms.traceWriter, cms.traceContext, nil)
 }
 
 // SetTracer sets the tracer for the MultiStore that the underlying

diff --git a/store/rootmulti/store_test.go b/store/rootmulti/store_test.go
@@ -912,3 +912,52 @@ func hashStores(stores map[types.StoreKey]types.CommitKVStore) []byte {
 	}
 	return sdkmaps.HashFromMap(m)
 }
+
+type MockListener struct {
+	stateCache []types.StoreKVPair
+}
+
+func (tl *MockListener) OnWrite(storeKey types.StoreKey, key []byte, value []byte, delete bool) error {
+	tl.stateCache = append(tl.stateCache, types.StoreKVPair{
+		StoreKey: storeKey.Name(),
+		Key:      key,
+		Value:    value,
+		Delete:   delete,
+	})
+	return nil
+}
+
+func TestStateListeners(t *testing.T) {
+	var db dbm.DB = dbm.NewMemDB()
+	ms := newMultiStoreWithMounts(db, pruningtypes.NewPruningOptions(pruningtypes.PruningNothing))
+
+	listener := &MockListener{}
+	ms.AddListeners(testStoreKey1, []types.WriteListener{listener})
+
+	require.NoError(t, ms.LoadLatestVersion())
+	cacheMulti := ms.CacheMultiStore()
+
+	store1 := cacheMulti.GetKVStore(testStoreKey1)
+	store1.Set([]byte{1}, []byte{1})
+	require.Empty(t, listener.stateCache)
+
+	// writes are observed when cache store commit.
+	cacheMulti.Write()
+	require.Equal(t, 1, len(listener.stateCache))
+
+	// test nested cache store
+	listener.stateCache = []types.StoreKVPair{}
+	nested := cacheMulti.CacheMultiStore()
+
+	store1 = nested.GetKVStore(testStoreKey1)
+	store1.Set([]byte{1}, []byte{1})
+	require.Empty(t, listener.stateCache)
+
+	// writes are not observed when nested cache store commit
+	nested.Write()
+	require.Empty(t, listener.stateCache)
+
+	// writes are observed when inner cache store commit
+	cacheMulti.Write()
+	require.Equal(t, 1, len(listener.stateCache))
+}