From 99a29191b1b3127039f9a456cd00126096f6b9b5 Mon Sep 17 00:00:00 2001
From: Elizabeth Engelman <emengelman@gmail.com>
Date: Wed, 2 Jan 2019 17:23:03 -0600
Subject: [PATCH] Clean up error logging

---
 statediff/builder/builder.go | 16 +++++++---------
 statediff/service/service.go | 24 ++++++++++++++++++------
 2 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/statediff/builder/builder.go b/statediff/builder/builder.go
index 131c3626f..22178b98f 100644
--- a/statediff/builder/builder.go
+++ b/statediff/builder/builder.go
@@ -50,12 +50,12 @@ func (sdb *builder) BuildStateDiff(oldStateRoot, newStateRoot common.Hash, block
 	// Generate tries for old and new states
 	oldTrie, err := trie.New(oldStateRoot, sdb.trieDB)
 	if err != nil {
-		log.Debug("error creating oldTrie", err)
+		log.Error("Error creating trie for oldStateRoot", "error", err)
 		return nil, err
 	}
 	newTrie, err := trie.New(newStateRoot, sdb.trieDB)
 	if err != nil {
-		log.Debug("error creating newTrie", err)
+		log.Error("Error creating trie for newStateRoot", "error", err)
 		return nil, err
 	}
 
@@ -64,7 +64,7 @@ func (sdb *builder) BuildStateDiff(oldStateRoot, newStateRoot common.Hash, block
 	newIt := newTrie.NodeIterator([]byte{})
 	creations, err := sdb.collectDiffNodes(oldIt, newIt)
 	if err != nil {
-		log.Debug("error collecting creation diff nodes", err)
+		log.Error("Error collecting creation diff nodes", "error", err)
 		return nil, err
 	}
 
@@ -73,7 +73,7 @@ func (sdb *builder) BuildStateDiff(oldStateRoot, newStateRoot common.Hash, block
 	newIt = newTrie.NodeIterator(make([]byte, 0))
 	deletions, err := sdb.collectDiffNodes(newIt, oldIt)
 	if err != nil {
-		log.Debug("error collecting deletion diff nodes", err)
+		log.Error("Error collecting deletion diff nodes", "error", err)
 		return nil, err
 	}
 
@@ -85,17 +85,17 @@ func (sdb *builder) BuildStateDiff(oldStateRoot, newStateRoot common.Hash, block
 	// Build and return the statediff
 	updatedAccounts, err := sdb.buildDiffIncremental(creations, deletions, updatedKeys)
 	if err != nil {
-		log.Debug("error building diff incremental for updated", err)
+		log.Error("Error building diff for updated accounts", "error", err)
 		return nil, err
 	}
 	createdAccounts, err := sdb.buildDiffEventual(creations, true)
 	if err != nil {
-		log.Debug("error building diff incremental for created", err)
+		log.Error("Error building diff for created accounts", "error", err)
 		return nil, err
 	}
 	deletedAccounts, err := sdb.buildDiffEventual(deletions, false)
 	if err != nil {
-		log.Debug("error building diff incremental for deleted", err)
+		log.Error("Error building diff for deleted accounts", "error", err)
 		return nil, err
 	}
 
@@ -260,9 +260,7 @@ func (sdb *builder) buildStorageDiffsIncremental(oldSR common.Hash, newSR common
 }
 
 func (sdb *builder) addressByPath(path []byte) (*common.Address, error) {
-	// db := core.PreimageTable(sdb.chainDb)
 	log.Debug("Looking up address from path", "path", hexutil.Encode(append([]byte("secure-key-"), path...)))
-	// if addrBytes,err := db.Get(path); err != nil {
 	if addrBytes, err := sdb.chainDB.Get(append([]byte("secure-key-"), hexToKeybytes(path)...)); err != nil {
 		log.Error("Error looking up address via path", "path", hexutil.Encode(append([]byte("secure-key-"), path...)), "error", err)
 		return nil, err
diff --git a/statediff/service/service.go b/statediff/service/service.go
index 86b74219c..42711339e 100644
--- a/statediff/service/service.go
+++ b/statediff/service/service.go
@@ -13,6 +13,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/log"
 )
 
 type BlockChain interface {
@@ -51,19 +52,30 @@ func (StateDiffService) APIs() []rpc.API {
 func (sds *StateDiffService) Loop(events chan core.ChainEvent) {
 	for elem := range events {
 		currentBlock := elem.Block
-
 		parentHash := currentBlock.ParentHash()
 		parentBlock := sds.BlockChain.GetBlockByHash(parentHash)
 
-		sds.Extractor.ExtractStateDiff(*parentBlock, *currentBlock)
+		stateDiffLocation, err := sds.Extractor.ExtractStateDiff(*parentBlock, *currentBlock)
+		if err != nil {
+			log.Error("Error extracting statediff", "block number", currentBlock.Number(), "error", err)
+		} else {
+			log.Info("Statediff extracted", "block number", currentBlock.Number(), "location", stateDiffLocation)
+		}
 	}
 }
 
+var eventsChannel chan core.ChainEvent
 func (sds *StateDiffService) Start(server *p2p.Server) error {
-	events := make(chan core.ChainEvent, 10)
-	sds.BlockChain.SubscribeChainEvent(events)
-	go sds.Loop(events)
+	log.Info("Starting statediff service")
+	eventsChannel := make(chan core.ChainEvent, 10)
+	sds.BlockChain.SubscribeChainEvent(eventsChannel)
+	go sds.Loop(eventsChannel)
 	return nil
 }
 
-func (StateDiffService) Stop() error { return nil }
+func (StateDiffService) Stop() error {
+	log.Info("Stopping statediff service")
+	close(eventsChannel)
+
+	return nil
+}