From e9a1d3bca8353ee206d262ab1fad2d7e3e0b24a5 Mon Sep 17 00:00:00 2001
From: Jimmy Hu <jimmy.hu@dexon.org>
Date: Mon, 15 Apr 2019 12:12:22 +0800
Subject: core: start next BA only when previous block delivered (#571)

---
 core/agreement-mgr.go   | 12 +++++++-----
 core/blockchain.go      |  7 +++++++
 core/blockchain_test.go |  1 +
 core/consensus.go       |  4 ++++
 4 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/core/agreement-mgr.go b/core/agreement-mgr.go
index 4597fe9..f65903d 100644
--- a/core/agreement-mgr.go
+++ b/core/agreement-mgr.go
@@ -564,11 +564,13 @@ func (mgr *agreementMgr) baRoutineForOneRound(
 			default:
 			}
 			nextHeight, nextTime = mgr.bcModule.nextBlock()
-			if isStop(restartPos) {
-				break
-			}
-			if nextHeight > restartPos.Height {
-				break
+			if nextHeight != notReadyHeight {
+				if isStop(restartPos) {
+					break
+				}
+				if nextHeight > restartPos.Height {
+					break
+				}
 			}
 			mgr.logger.Debug("BlockChain not ready!!!",
 				"old", oldPos, "restart", restartPos, "next", nextHeight)
diff --git a/core/blockchain.go b/core/blockchain.go
index 1efd867..4fae221 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"math"
 	"sort"
 	"sync"
 	"time"
@@ -49,6 +50,8 @@ var (
 	ErrMissingRandomness = errors.New("missing block randomness")
 )
 
+const notReadyHeight uint64 = math.MaxUint64
+
 type pendingBlockRecord struct {
 	position types.Position
 	block    *types.Block
@@ -384,6 +387,10 @@ func (bc *blockChain) nextBlock() (uint64, time.Time) {
 	if tip == nil {
 		return types.GenesisHeight, bc.dMoment
 	}
+	if tip != bc.lastDelivered {
+		// If tip is not delivered, we should not proceed to next block.
+		return notReadyHeight, time.Time{}
+	}
 	return tip.Position.Height + 1, tip.Timestamp.Add(config.minBlockInterval)
 }
 
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index ea604a2..c3d2cb7 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -415,6 +415,7 @@ func (s *BlockChainTestSuite) TestNextBlockAndTipRound() {
 	s.Require().Equal(nextT, s.dMoment)
 	// Add one block.
 	s.Require().NoError(bc.addBlock(blocks[0]))
+	s.Require().Len(bc.extractBlocks(), 1)
 	nextH, nextT = bc.nextBlock()
 	s.Require().Equal(nextH, uint64(2))
 	s.Require().Equal(
diff --git a/core/consensus.go b/core/consensus.go
index 7c44bdf..ba7d8fd 100644
--- a/core/consensus.go
+++ b/core/consensus.go
@@ -1148,6 +1148,10 @@ func (con *Consensus) generateBlockRandomness(blocks []*types.Block) {
 					"block", block,
 					"result", result)
 				con.network.BroadcastAgreementResult(result)
+				if err := con.deliverFinalizedBlocks(); err != nil {
+					con.logger.Error("Failed to deliver finalized block",
+						"error", err)
+				}
 			}
 		}(block)
 	}
-- 
cgit v1.2.3