Merge pull request #1577 from chaosma/cx_rpc

add rpc call to resend missing cross shard receipt

core/blockchain.go

@@ -2238,3 +2238,10 @@ func (bc *BlockChain) UpdateCXReceiptsCheckpointsByBlock(block *types.Block) {
 		bc.updateCXReceiptsCheckpoints(k, v)
 	}
 }
+
+// ReadTxLookupEntry returns where the given transaction resides in the chain,
+// as a (block hash, block number, index in transaction list) triple.
+// returns 0, 0 if not found
+func (bc *BlockChain) ReadTxLookupEntry(txID common.Hash) (common.Hash, uint64, uint64) {
+	return rawdb.ReadTxLookupEntry(bc.db, txID)
+}

core/cx_pool.go

@@ -0,0 +1,58 @@
+package core
+
+import (
+	mapset "github.com/deckarep/golang-set"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+const (
+	// CxPoolSize is the maximum size of the pool
+	CxPoolSize = 50
+)
+
+// CxEntry represents the egress receipt's blockHash and ToShardID
+type CxEntry struct {
+	BlockHash common.Hash
+	ToShardID uint32
+}
+
+// CxPool is to hold a pool of block outgoing receipts to be resend in next round broadcast
+// When a user/client doesn't find the destination shard get the money from cross shard tx
+// it can send RPC call along with txID to allow the any validator to
+// add the corresponding block's receipts to be resent
+type CxPool struct {
+	pool    mapset.Set
+	maxSize int
+}
+
+// NewCxPool creates a new CxPool
+func NewCxPool(limit int) *CxPool {
+	pool := mapset.NewSet()
+	cxPool := CxPool{pool: pool, maxSize: limit}
+	return &cxPool
+}
+
+// Pool returns the pool of blockHashes of missing receipts
+func (cxPool *CxPool) Pool() mapset.Set {
+	return cxPool.pool
+}
+
+// Size return size of the pool
+func (cxPool *CxPool) Size() int {
+	return cxPool.pool.Cardinality()
+}
+
+// Add add element into the pool if not exceed limit
+func (cxPool *CxPool) Add(entry CxEntry) bool {
+	if cxPool.Size() > cxPool.maxSize {
+		return false
+	}
+	cxPool.pool.Add(entry)
+	return true
+}
+
+// Clear empty the pool
+func (cxPool *CxPool) Clear() {
+	cxPool.pool.Clear()
+}

hmy/api_backend.go

@@ -232,3 +232,24 @@ func (b *APIBackend) RPCGasCap() *big.Int {
 func (b *APIBackend) GetShardID() uint32 {
 	return b.hmy.shardID
 }
+
+// ResendCx retrieve blockHash from txID and add blockHash to CxPool for resending
+func (b *APIBackend) ResendCx(ctx context.Context, txID common.Hash) (uint64, bool) {
+	blockHash, blockNum, index := b.hmy.BlockChain().ReadTxLookupEntry(txID)
+	blk := b.hmy.BlockChain().GetBlockByHash(blockHash)
+	if blk == nil {
+		return 0, false
+	}
+	txs := blk.Transactions()
+	// a valid index is from 0 to len-1
+	if int(index) > len(txs)-1 {
+		return 0, false
+	}
+	tx := txs[int(index)]
+	if tx.ShardID() == tx.ToShardID() || blk.Header().ShardID() != tx.ShardID() {
+		return 0, false
+	}
+	entry := core.CxEntry{blockHash, tx.ToShardID()}
+	success := b.hmy.CxPool().Add(entry)
+	return blockNum, success
+}

hmy/backend.go

@@ -21,6 +21,7 @@ type Harmony struct {
 
 	blockchain     *core.BlockChain
 	txPool         *core.TxPool
+	cxPool         *core.CxPool
 	accountManager *accounts.Manager
 	eventMux       *event.TypeMux
 	// DB interfaces
@@ -51,13 +52,14 @@ type NodeAPI interface {
 
 // New creates a new Harmony object (including the
 // initialisation of the common Harmony object)
-func New(nodeAPI NodeAPI, txPool *core.TxPool, eventMux *event.TypeMux, shardID uint32) (*Harmony, error) {
+func New(nodeAPI NodeAPI, txPool *core.TxPool, cxPool *core.CxPool, eventMux *event.TypeMux, shardID uint32) (*Harmony, error) {
 	chainDb := nodeAPI.Blockchain().ChainDB()
 	hmy := &Harmony{
 		shutdownChan:   make(chan bool),
 		bloomRequests:  make(chan chan *bloombits.Retrieval),
 		blockchain:     nodeAPI.Blockchain(),
 		txPool:         txPool,
+		cxPool:         cxPool,
 		accountManager: nodeAPI.AccountManager(),
 		eventMux:       eventMux,
 		chainDb:        chainDb,
@@ -75,6 +77,9 @@ func New(nodeAPI NodeAPI, txPool *core.TxPool, eventMux *event.TypeMux, shardID
 // TxPool ...
 func (s *Harmony) TxPool() *core.TxPool { return s.txPool }
 
+// CxPool is used to store the blockHashes, where the corresponding block contains the cross shard receipts to be sent
+func (s *Harmony) CxPool() *core.CxPool { return s.cxPool }
+
 // BlockChain ...
 func (s *Harmony) BlockChain() *core.BlockChain { return s.blockchain }
 

internal/hmyapi/backend.go

@@ -64,6 +64,9 @@ type Backend interface {
 	// Get balance
 	GetBalance(address common.Address) (*hexutil.Big, error)
 	GetShardID() uint32
+
+	// retrieve the blockHash using txID and add blockHash to CxPool for resending
+	ResendCx(ctx context.Context, txID common.Hash) (uint64, bool)
 }
 
 // GetAPIs returns all the APIs.

internal/hmyapi/blockchain.go

@@ -112,6 +112,16 @@ func (s *PublicBlockChainAPI) BlockNumber() hexutil.Uint64 {
 	return hexutil.Uint64(header.Number().Uint64())
 }
 
+// ResendCx requests that the egress receipt for the given cross-shard
+// transaction be sent to the destination shard for credit.  This is used for
+// unblocking a half-complete cross-shard transaction whose fund has been
+// withdrawn already from the source shard but not credited yet in the
+// destination account due to transient failures.
+func (s *PublicBlockChainAPI) ResendCx(ctx context.Context, txID common.Hash) (bool, error) {
+	_, success := s.b.ResendCx(ctx, txID)
+	return success, nil
+}
+
 // Call executes the given transaction on the state for the given block number.
 // It doesn't make and changes in the state/blockchain and is useful to execute and retrieve values.
 func (s *PublicBlockChainAPI) Call(ctx context.Context, args CallArgs, blockNr rpc.BlockNumber) (hexutil.Bytes, error) {

node/node.go

@@ -120,6 +120,8 @@ type Node struct {
 
 	TxPool *core.TxPool // TODO migrate to TxPool from pendingTransactions list below
 
+	CxPool *core.CxPool // pool for missing cross shard receipts resend
+
 	pendingTransactions types.Transactions // All the transactions received but not yet processed for Consensus
 	pendingTxMutex      sync.Mutex
 	recentTxsStats      types.RecentTxsStats
@@ -391,6 +393,7 @@ func New(host p2p.Host, consensusObj *consensus.Consensus, chainDBFactory shardc
 		node.BeaconBlockChannel = make(chan *types.Block)
 		node.recentTxsStats = make(types.RecentTxsStats)
 		node.TxPool = core.NewTxPool(core.DefaultTxPoolConfig, node.Blockchain().Config(), blockchain)
+		node.CxPool = core.NewCxPool(core.CxPoolSize)
 		node.Worker = worker.New(node.Blockchain().Config(), blockchain, chain.Engine, node.Consensus.ShardID)
 		if node.Blockchain().ShardID() != 0 {
 			node.BeaconWorker = worker.New(node.Beaconchain().Config(), beaconChain, chain.Engine, node.Consensus.ShardID)

node/node_cross_shard.go

@@ -47,20 +47,56 @@ func (node *Node) BroadcastCXReceipts(newBlock *types.Block, lastCommits []byte)
 		if i == int(myShardID) {
 			continue
 		}
-		cxReceipts, err := node.Blockchain().ReadCXReceipts(uint32(i), newBlock.NumberU64(), newBlock.Hash(), false)
-		if err != nil || len(cxReceipts) == 0 {
-			utils.Logger().Warn().Err(err).Uint32("ToShardID", uint32(i)).Int("numCXReceipts", len(cxReceipts)).Msg("[BroadcastCXReceipts] No ReadCXReceipts found")
+		go node.BroadcastCXReceiptsWithShardID(newBlock, commitSig, commitBitmap, uint32(i))
+	}
+}
+
+// BroadcastCXReceiptsWithShardID broadcasts cross shard receipts to given ToShardID
+func (node *Node) BroadcastCXReceiptsWithShardID(block *types.Block, commitSig []byte, commitBitmap []byte, toShardID uint32) {
+	myShardID := node.Consensus.ShardID
+	utils.Logger().Info().Uint32("toShardID", toShardID).Uint32("myShardID", myShardID).Uint64("blockNum", block.NumberU64()).Msg("[BroadcastCXReceiptsWithShardID]")
+
+	cxReceipts, err := node.Blockchain().ReadCXReceipts(toShardID, block.NumberU64(), block.Hash(), false)
+	if err != nil || len(cxReceipts) == 0 {
+		utils.Logger().Warn().Err(err).Uint32("ToShardID", toShardID).Int("numCXReceipts", len(cxReceipts)).Msg("[BroadcastCXReceiptsWithShardID] No ReadCXReceipts found")
+		return
+	}
+	merkleProof, err := node.Blockchain().CXMerkleProof(toShardID, block)
+	if err != nil {
+		utils.Logger().Warn().Uint32("ToShardID", toShardID).Msg("[BroadcastCXReceiptsWithShardID] Unable to get merkleProof")
+		return
+	}
+	utils.Logger().Info().Uint32("ToShardID", toShardID).Msg("[BroadcastCXReceiptsWithShardID] ReadCXReceipts and MerkleProof Found")
+
+	groupID := p2p.ShardID(toShardID)
+	go node.host.SendMessageToGroups([]p2p.GroupID{p2p.NewGroupIDByShardID(groupID)}, host.ConstructP2pMessage(byte(0), proto_node.ConstructCXReceiptsProof(cxReceipts, merkleProof, block.Header(), commitSig, commitBitmap)))
+}
+
+// BroadcastMissingCXReceipts broadcasts missing cross shard receipts per request
+func (node *Node) BroadcastMissingCXReceipts() {
+	sendNextTime := []core.CxEntry{}
+	it := node.CxPool.Pool().Iterator()
+	for entry := range it.C {
+		cxEntry := entry.(core.CxEntry)
+		toShardID := cxEntry.ToShardID
+		blk := node.Blockchain().GetBlockByHash(cxEntry.BlockHash)
+		if blk == nil {
 			continue
 		}
-		merkleProof, err := node.Blockchain().CXMerkleProof(uint32(i), newBlock)
-		if err != nil {
-			utils.Logger().Warn().Uint32("ToShardID", uint32(i)).Msg("[BroadcastCXReceipts] Unable to get merkleProof")
+		blockNum := blk.NumberU64()
+		nextHeader := node.Blockchain().GetHeaderByNumber(blockNum + 1)
+		if nextHeader == nil {
+			sendNextTime = append(sendNextTime, cxEntry)
 			continue
 		}
-		utils.Logger().Info().Uint32("ToShardID", uint32(i)).Msg("[BroadcastCXReceipts] ReadCXReceipts and MerkleProof Found")
-
-		groupID := p2p.ShardID(i)
-		go node.host.SendMessageToGroups([]p2p.GroupID{p2p.NewGroupIDByShardID(groupID)}, host.ConstructP2pMessage(byte(0), proto_node.ConstructCXReceiptsProof(cxReceipts, merkleProof, newBlock.Header(), commitSig, commitBitmap)))
+		sig := nextHeader.LastCommitSignature()
+		bitmap := nextHeader.LastCommitBitmap()
+		go node.BroadcastCXReceiptsWithShardID(blk, sig[:], bitmap, toShardID)
+	}
+	node.CxPool.Clear()
+	// this should not happen or maybe happen for impatient user
+	for _, entry := range sendNextTime {
+		node.CxPool.Add(entry)
 	}
 }
 

node/node_handler.go

@@ -392,6 +392,8 @@ func (node *Node) PostConsensusProcessing(newBlock *types.Block, commitSigAndBit
 		}
 	}
 
+	node.BroadcastMissingCXReceipts()
+
 	// TODO chao: uncomment this after beacon syncing is stable
 	// node.Blockchain().UpdateCXReceiptsCheckpointsByBlock(newBlock)
 

node/rpc.go

@@ -46,7 +46,7 @@ var (
 // StartRPC start RPC service
 func (node *Node) StartRPC(nodePort string) error {
 	// Gather all the possible APIs to surface
-	harmony, _ = hmy.New(node, node.TxPool, new(event.TypeMux), node.Consensus.ShardID)
+	harmony, _ = hmy.New(node, node.TxPool, node.CxPool, new(event.TypeMux), node.Consensus.ShardID)
 
 	apis := node.APIs()