From f8051da0bd0e2dae25c34c1dd76d2501d0349c7a Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <evgeniy@nspcc.ru>
Date: Mon, 22 Jun 2020 10:49:48 +0300
Subject: [PATCH] core: extend Blockchainer interface with StateHeight()

Allow to query current verified state root height.
---
 pkg/core/blockchain.go        | 6 ++++++
 pkg/core/blockchainer.go      | 1 +
 pkg/network/helper_test.go    | 4 +++-
 pkg/rpc/server/server.go      | 5 ++---
 pkg/rpc/server/server_test.go | 5 ++---
 5 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/pkg/core/blockchain.go b/pkg/core/blockchain.go
index e311db644..528002435 100644
--- a/pkg/core/blockchain.go
+++ b/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)
diff --git a/pkg/core/blockchainer.go b/pkg/core/blockchainer.go
index db2d11abe..d32a3eb5e 100644
--- a/pkg/core/blockchainer.go
+++ b/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)
diff --git a/pkg/network/helper_test.go b/pkg/network/helper_test.go
index 2e2b697ad..0bc0b6637 100644
--- a/pkg/network/helper_test.go
+++ b/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")
 }
diff --git a/pkg/rpc/server/server.go b/pkg/rpc/server/server.go
index 6912c4e24..675efc9b7 100644
--- a/pkg/rpc/server/server.go
+++ b/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,
-		StateHeight: height,
+		BlockHeight: s.chain.BlockHeight(),
+		StateHeight: s.chain.StateHeight(),
 	}, nil
 }
 
diff --git a/pkg/rpc/server/server_test.go b/pkg/rpc/server/server_test.go
index e53687baf..509867121 100644
--- a/pkg/rpc/server/server_test.go
+++ b/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, h, sh.BlockHeight)
-				require.Equal(t, h, sh.StateHeight)
+				require.Equal(t, e.chain.BlockHeight(), sh.BlockHeight)
+				require.Equal(t, e.chain.StateHeight(), sh.StateHeight)
 			},
 		},
 	},