Add a fix for the database

Author: Aurélien Richez

src/main/scala/io/iohk/ethereum/nodebuilder/StdNode.scala

@@ -1,13 +1,13 @@
 package io.iohk.ethereum.nodebuilder
 
 import akka.actor.typed.ActorSystem
+import akka.util.ByteString
 
 import scala.concurrent.Await
 import scala.concurrent.ExecutionContext.Implicits.global
 import scala.util.Failure
 import scala.util.Success
 import scala.util.Try
-
 import io.iohk.ethereum.blockchain.sync.SyncProtocol
 import io.iohk.ethereum.consensus.mining.StdMiningBuilder
 import io.iohk.ethereum.metrics.Metrics
@@ -17,7 +17,7 @@ import io.iohk.ethereum.network.ServerActor
 import io.iohk.ethereum.network.discovery.PeerDiscoveryManager
 import io.iohk.ethereum.nodebuilder.tooling.PeriodicConsistencyCheck
 import io.iohk.ethereum.nodebuilder.tooling.StorageConsistencyChecker
-import io.iohk.ethereum.utils.Config
+import io.iohk.ethereum.utils.{Config, Hex}
 
 /** A standard node is everything Ethereum prescribes except the mining algorithm,
   * which is plugged in dynamically.
@@ -32,6 +32,8 @@ abstract class BaseNode extends Node {
   def start(): Unit = {
     startMetricsClient()
 
+    fixDatabase()
+
     loadGenesisData()
 
     runDBConsistencyCheck()
@@ -132,6 +134,24 @@ abstract class BaseNode extends Node {
     tryAndLogFailure(() => Metrics.get().close())
     tryAndLogFailure(() => storagesInstance.dataSource.close())
   }
+
+  def fixDatabase(): Unit = {
+    // FIXME this is a temporary solution to avoid an incompatibility due to the introduction of the best block hash
+    // We can remove this fix when we release an incompatible version.
+    val bestBlockInfo = storagesInstance.storages.appStateStorage.getBestBlockInfo()
+    if (bestBlockInfo.hash == ByteString.empty && bestBlockInfo.number > 0) {
+      log.warn("Fixing best block hash into database for block {}", bestBlockInfo.number)
+      storagesInstance.storages.blockNumberMappingStorage.get(bestBlockInfo.number) match {
+        case Some(hash) =>
+          log.warn("Putting {} as the best block hash", Hex.toHexString(hash.toArray))
+          storagesInstance.storages.appStateStorage.putBestBlockInfo(bestBlockInfo.copy(hash = hash))
+        case None =>
+          log.error("No block found for number {} when trying to fix database", bestBlockInfo.number)
+      }
+
+    }
+
+  }
 }
 
 class StdNode extends BaseNode with StdMiningBuilder