From 0f0032e652a41a811325648dd60108f753656d2a Mon Sep 17 00:00:00 2001
From: Jaynti Kanani <jdkanani@gmail.com>
Date: Thu, 29 Oct 2020 18:59:18 +0530
Subject: [PATCH] fix: websocket subscribe for state sync logs

---
 core/blockchain.go        | 21 ++++++++++++++++++++-
 core/types/bor_receipt.go | 17 +++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/core/blockchain.go b/core/blockchain.go
index b77978042b..8b048d26a8 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1457,16 +1457,23 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 	//
 	// block logs = receipt logs + state sync logs = `state.Logs()`
 	blockLogs := state.Logs()
+	var stateSyncLogs []*types.Log
 	if len(blockLogs) > 0 {
 		sort.SliceStable(blockLogs, func(i, j int) bool {
 			return blockLogs[i].Index < blockLogs[j].Index
 		})
 
 		if len(blockLogs) > len(logs) {
+			stateSyncLogs = blockLogs[len(logs):] // get state-sync logs from `state.Logs()`
+
+			// State sync logs don't have tx index, tx hash and other necessary fields
+			// DeriveFieldsForBorLogs will fill those fields for websocket subscriptions
+			types.DeriveFieldsForBorLogs(stateSyncLogs, block.Hash(), block.NumberU64(), uint(len(receipts)), uint(len(logs)))
+
 			// Write bor receipt
 			rawdb.WriteBorReceipt(blockBatch, block.Hash(), block.NumberU64(), &types.ReceiptForStorage{
 				Status: types.ReceiptStatusSuccessful, // make receipt status successful
-				Logs:   blockLogs[len(logs):],         // get state-sync logs from `state.Logs()`
+				Logs:   stateSyncLogs,
 			})
 
 			// Write bor tx reverse lookup
@@ -1577,6 +1584,12 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 		if len(logs) > 0 {
 			bc.logsFeed.Send(logs)
 		}
+
+		// send state sync logs into logs feed
+		if len(stateSyncLogs) > 0 {
+			bc.logsFeed.Send(stateSyncLogs)
+		}
+
 		// In theory we should fire a ChainHeadEvent when we inject
 		// a canonical block, but sometimes we can insert a batch of
 		// canonicial blocks. Avoid firing too much ChainHeadEvents,
@@ -2091,6 +2104,12 @@ func (bc *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 			}
 			receipts := rawdb.ReadReceipts(bc.db, hash, *number, bc.chainConfig)
 
+			// Append bor receipt
+			borReceipt := rawdb.ReadBorReceipt(bc.db, hash, *number)
+			if borReceipt != nil {
+				receipts = append(receipts, borReceipt)
+			}
+
 			var logs []*types.Log
 			for _, receipt := range receipts {
 				for _, log := range receipt.Logs {
diff --git a/core/types/bor_receipt.go b/core/types/bor_receipt.go
index e00739f094..821bfbe268 100644
--- a/core/types/bor_receipt.go
+++ b/core/types/bor_receipt.go
@@ -63,6 +63,23 @@ func DeriveFieldsForBorReceipt(receipt *Receipt, hash common.Hash, number uint64
 	return nil
 }
 
+// DeriveFieldsForBorLogs fills the receipts with their computed fields based on consensus
+// data and contextual infos like containing block and transactions.
+func DeriveFieldsForBorLogs(logs []*Log, hash common.Hash, number uint64, txIndex uint, logIndex uint) {
+	// get derived tx hash
+	txHash := GetDerivedBorTxHash(BorReceiptKey(number, hash))
+
+	// the derived log fields can simply be set from the block and transaction
+	for j := 0; j < len(logs); j++ {
+		logs[j].BlockNumber = number
+		logs[j].BlockHash = hash
+		logs[j].TxHash = txHash
+		logs[j].TxIndex = txIndex
+		logs[j].Index = logIndex
+		logIndex++
+	}
+}
+
 // MergeBorLogs merges receipt logs and block receipt logs
 func MergeBorLogs(logs []*Log, borLogs []*Log) []*Log {
 	result := append(logs, borLogs...)