core: extend Blockchainer interface with StateHeight()

Allow to query current verified state root height.

pkg/core/blockchain.go

@@ -1776,6 +1776,12 @@ func (bc *Blockchain) isTxStillRelevant(t *transaction.Transaction) bool {
 
 }
 
+// StateHeight returns height of the verified state root.
+func (bc *Blockchain) StateHeight() uint32 {
+	h, _ := bc.dao.GetCurrentStateRootHeight()
+	return h
+}
+
 // AddStateRoot add new (possibly unverified) state root to the blockchain.
 func (bc *Blockchain) AddStateRoot(r *state.MPTRoot) error {
 	our, err := bc.GetStateRoot(r.Index)

pkg/core/blockchainer.go

@@ -49,6 +49,7 @@ type Blockchainer interface {
 	References(t *transaction.Transaction) ([]transaction.InOut, error)
 	mempool.Feer // fee interface
 	PoolTx(*transaction.Transaction) error
+	StateHeight() uint32
 	SubscribeForBlocks(ch chan<- *block.Block)
 	SubscribeForExecutions(ch chan<- *state.AppExecResult)
 	SubscribeForNotifications(ch chan<- *state.NotificationEvent)

pkg/network/helper_test.go

@@ -154,7 +154,9 @@ func (chain testChain) IsLowPriority(util.Fixed8) bool {
 func (chain testChain) PoolTx(*transaction.Transaction) error {
 	panic("TODO")
 }
-
+func (chain testChain) StateHeight() uint32 {
+	panic("TODO")
+}
 func (chain testChain) SubscribeForBlocks(ch chan<- *block.Block) {
 	panic("TODO")
 }

pkg/rpc/server/server.go

@@ -745,10 +745,9 @@ func (s *Server) verifyProof(ps request.Params) (interface{}, *response.Error) {
 }
 
 func (s *Server) getStateHeight(_ request.Params) (interface{}, *response.Error) {
-	height := s.chain.BlockHeight()
 	return &result.StateHeight{
-		BlockHeight: height,
+		BlockHeight: s.chain.BlockHeight(),
-		StateHeight: height,
+		StateHeight: s.chain.StateHeight(),
 	}, nil
 }
 

pkg/rpc/server/server_test.go

@@ -246,9 +246,8 @@ var rpcTestCases = map[string][]rpcTestCase{
 				sh, ok := res.(*result.StateHeight)
 				require.True(t, ok)
 
-				h := e.chain.BlockHeight()
+				require.Equal(t, e.chain.BlockHeight(), sh.BlockHeight)
-				require.Equal(t, h, sh.BlockHeight)
+				require.Equal(t, e.chain.StateHeight(), sh.StateHeight)
-				require.Equal(t, h, sh.StateHeight)
 			},
 		},
 	},