Add recommended_feerates optional message

eclair-core/src/main/scala/fr/acinq/eclair/Eclair.scala

@@ -381,9 +381,9 @@ class EclairImpl(appKit: Kit) extends Eclair with Logging {
   override def sendOnChain(address: String, amount: Satoshi, confirmationTargetOrFeerate: Either[Long, FeeratePerByte]): Future[TxId] = {
     val feeRate = confirmationTargetOrFeerate match {
       case Left(blocks) =>
-        if (blocks < 3) appKit.nodeParams.currentFeerates.fast
-        else if (blocks > 6) appKit.nodeParams.currentFeerates.slow
-        else appKit.nodeParams.currentFeerates.medium
+        if (blocks < 3) appKit.nodeParams.currentBitcoinCoreFeerates.fast
+        else if (blocks > 6) appKit.nodeParams.currentBitcoinCoreFeerates.slow
+        else appKit.nodeParams.currentBitcoinCoreFeerates.medium
       case Right(feeratePerByte) => FeeratePerKw(feeratePerByte)
     }
     appKit.wallet match {

eclair-core/src/main/scala/fr/acinq/eclair/NodeParams.scala

@@ -21,9 +21,9 @@ import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
 import fr.acinq.bitcoin.scalacompat.{Block, BlockHash, Crypto, Satoshi, SatoshiLong}
 import fr.acinq.eclair.Setup.Seeds
 import fr.acinq.eclair.blockchain.fee._
-import fr.acinq.eclair.channel.ChannelFlags
 import fr.acinq.eclair.channel.fsm.Channel
 import fr.acinq.eclair.channel.fsm.Channel.{BalanceThreshold, ChannelConf, UnhandledExceptionStrategy}
+import fr.acinq.eclair.channel.{ChannelFlags, ChannelTypes}
 import fr.acinq.eclair.crypto.Noise.KeyPair
 import fr.acinq.eclair.crypto.keymanager.{ChannelKeyManager, NodeKeyManager, OnChainKeyManager}
 import fr.acinq.eclair.db._
@@ -36,6 +36,7 @@ import fr.acinq.eclair.router.Graph.{HeuristicsConstants, WeightRatios}
 import fr.acinq.eclair.router.Router._
 import fr.acinq.eclair.router.{Graph, PathFindingExperimentConf}
 import fr.acinq.eclair.tor.Socks5ProxyParams
+import fr.acinq.eclair.transactions.Transactions
 import fr.acinq.eclair.wire.protocol._
 import grizzled.slf4j.Logging
 import scodec.bits.ByteVector
@@ -57,7 +58,7 @@ case class NodeParams(nodeKeyManager: NodeKeyManager,
                       onChainKeyManager_opt: Option[OnChainKeyManager],
                       instanceId: UUID, // a unique instance ID regenerated after each restart
                       private val blockHeight: AtomicLong,
-                      private val feerates: AtomicReference[FeeratesPerKw],
+                      private val bitcoinCoreFeerates: AtomicReference[FeeratesPerKw],
                       alias: String,
                       color: Color,
                       publicAddresses: List[NodeAddress],
@@ -102,13 +103,34 @@ case class NodeParams(nodeKeyManager: NodeKeyManager,
 
   def currentBlockHeight: BlockHeight = BlockHeight(blockHeight.get)
 
-  def currentFeerates: FeeratesPerKw = feerates.get()
+  def currentBitcoinCoreFeerates: FeeratesPerKw = bitcoinCoreFeerates.get()
 
   /** Only to be used in tests. */
-  def setFeerates(value: FeeratesPerKw): Unit = feerates.set(value)
+  def setBitcoinCoreFeerates(value: FeeratesPerKw): Unit = bitcoinCoreFeerates.set(value)
 
   /** Returns the features that should be used in our init message with the given peer. */
   def initFeaturesFor(nodeId: PublicKey): Features[InitFeature] = overrideInitFeatures.getOrElse(nodeId, features).initFeatures()
+
+  /** Returns the feerates we'd like our peer to use when funding channels. */
+  def recommendedFeerates(remoteNodeId: PublicKey, localFeatures: Features[InitFeature], remoteFeatures: Features[InitFeature]): RecommendedFeerates = {
+    val feerateTolerance = onChainFeeConf.feerateToleranceFor(remoteNodeId)
+    val fundingFeerate = onChainFeeConf.getFundingFeerate(currentBitcoinCoreFeerates)
+    val fundingRange = RecommendedFeeratesTlv.FundingFeerateRange(
+      min = fundingFeerate * feerateTolerance.ratioLow,
+      max = fundingFeerate * feerateTolerance.ratioHigh,
+    )
+    // We use the most likely commitment format, even though there is no guarantee that this is the one that will be used.
+    val commitmentFormat = ChannelTypes.defaultFromFeatures(localFeatures, remoteFeatures, announceChannel = false).commitmentFormat
+    val commitmentFeerate = onChainFeeConf.getCommitmentFeerate(currentBitcoinCoreFeerates, remoteNodeId, commitmentFormat, channelConf.minFundingPrivateSatoshis)
+    val commitmentRange = RecommendedFeeratesTlv.CommitmentFeerateRange(
+      min = commitmentFeerate * feerateTolerance.ratioLow,
+      max = commitmentFormat match {
+        case Transactions.DefaultCommitmentFormat => commitmentFeerate * feerateTolerance.ratioHigh
+        case _: Transactions.AnchorOutputsCommitmentFormat => (commitmentFeerate * feerateTolerance.ratioHigh).max(feerateTolerance.anchorOutputMaxCommitFeerate)
+      },
+    )
+    RecommendedFeerates(chainHash, fundingFeerate, commitmentFeerate, TlvStream(fundingRange, commitmentRange))
+  }
 }
 
 case class PaymentFinalExpiryConf(min: CltvExpiryDelta, max: CltvExpiryDelta) {
@@ -219,7 +241,7 @@ object NodeParams extends Logging {
 
   def makeNodeParams(config: Config, instanceId: UUID,
                      nodeKeyManager: NodeKeyManager, channelKeyManager: ChannelKeyManager, onChainKeyManager_opt: Option[OnChainKeyManager],
-                     torAddress_opt: Option[NodeAddress], database: Databases, blockHeight: AtomicLong, feerates: AtomicReference[FeeratesPerKw],
+                     torAddress_opt: Option[NodeAddress], database: Databases, blockHeight: AtomicLong, bitcoinCoreFeerates: AtomicReference[FeeratesPerKw],
                      pluginParams: Seq[PluginParams] = Nil): NodeParams = {
     // check configuration for keys that have been renamed
     val deprecatedKeyPaths = Map(
@@ -513,7 +535,7 @@ object NodeParams extends Logging {
       onChainKeyManager_opt = onChainKeyManager_opt,
       instanceId = instanceId,
       blockHeight = blockHeight,
-      feerates = feerates,
+      bitcoinCoreFeerates = bitcoinCoreFeerates,
       alias = nodeAlias,
       color = Color(color(0), color(1), color(2)),
       publicAddresses = addresses,

eclair-core/src/main/scala/fr/acinq/eclair/Setup.scala

@@ -255,7 +255,7 @@ class Setup(val datadir: File,
           blockchain.Monitoring.Metrics.FeeratesPerByte.withTag(blockchain.Monitoring.Tags.Priority, blockchain.Monitoring.Tags.Priorities.Medium).update(feeratesPerKw.get.medium.toLong.toDouble)
           blockchain.Monitoring.Metrics.FeeratesPerByte.withTag(blockchain.Monitoring.Tags.Priority, blockchain.Monitoring.Tags.Priorities.Fast).update(feeratesPerKw.get.fast.toLong.toDouble)
           blockchain.Monitoring.Metrics.FeeratesPerByte.withTag(blockchain.Monitoring.Tags.Priority, blockchain.Monitoring.Tags.Priorities.Fastest).update(feeratesPerKw.get.fastest.toLong.toDouble)
-          system.eventStream.publish(CurrentFeerates(feeratesPerKw.get))
+          system.eventStream.publish(CurrentFeerates.BitcoinCore(feeratesPerKw.get))
           logger.info(s"current feeratesPerKB=$feeratesPerKB feeratesPerKw=${feeratesPerKw.get}")
           feeratesRetrieved.trySuccess(Done)
         case Failure(exception) =>

eclair-core/src/main/scala/fr/acinq/eclair/blockchain/BlockchainEvents.scala

@@ -32,4 +32,14 @@ case class NewTransaction(tx: Transaction) extends BlockchainEvent
 
 case class CurrentBlockHeight(blockHeight: BlockHeight) extends BlockchainEvent
 
-case class CurrentFeerates(feeratesPerKw: FeeratesPerKw) extends BlockchainEvent
+sealed trait CurrentFeerates extends BlockchainEvent {
+  val feeratesPerKw: FeeratesPerKw
+}
+
+object CurrentFeerates {
+  //@formatter:off
+  case class BitcoinCore(feeratesPerKw: FeeratesPerKw) extends CurrentFeerates
+  //@formatter:on
+}
+
+

eclair-core/src/main/scala/fr/acinq/eclair/channel/Helpers.scala

@@ -119,7 +119,7 @@ object Helpers {
     val channelFeatures = ChannelFeatures(channelType, localFeatures, remoteFeatures, open.channelFlags.announceChannel)
 
     // BOLT #2: The receiving node MUST fail the channel if: it considers feerate_per_kw too small for timely processing or unreasonably large.
-    val localFeeratePerKw = nodeParams.onChainFeeConf.getCommitmentFeerate(nodeParams.currentFeerates, remoteNodeId, channelFeatures.commitmentFormat, open.fundingSatoshis)
+    val localFeeratePerKw = nodeParams.onChainFeeConf.getCommitmentFeerate(nodeParams.currentBitcoinCoreFeerates, remoteNodeId, channelFeatures.commitmentFormat, open.fundingSatoshis)
     if (nodeParams.onChainFeeConf.feerateToleranceFor(remoteNodeId).isFeeDiffTooHigh(channelFeatures.commitmentFormat, localFeeratePerKw, open.feeratePerKw)) return Left(FeerateTooDifferent(open.temporaryChannelId, localFeeratePerKw, open.feeratePerKw))
 
     // we don't check that the funder's amount for the initial commitment transaction is sufficient for full fee payment
@@ -166,7 +166,7 @@ object Helpers {
     val channelFeatures = ChannelFeatures(channelType, localFeatures, remoteFeatures, open.channelFlags.announceChannel)
 
     // BOLT #2: The receiving node MUST fail the channel if: it considers feerate_per_kw too small for timely processing or unreasonably large.
-    val localFeeratePerKw = nodeParams.onChainFeeConf.getCommitmentFeerate(nodeParams.currentFeerates, remoteNodeId, channelFeatures.commitmentFormat, open.fundingAmount)
+    val localFeeratePerKw = nodeParams.onChainFeeConf.getCommitmentFeerate(nodeParams.currentBitcoinCoreFeerates, remoteNodeId, channelFeatures.commitmentFormat, open.fundingAmount)
     if (nodeParams.onChainFeeConf.feerateToleranceFor(remoteNodeId).isFeeDiffTooHigh(channelFeatures.commitmentFormat, localFeeratePerKw, open.commitmentFeerate)) return Left(FeerateTooDifferent(open.temporaryChannelId, localFeeratePerKw, open.commitmentFeerate))
 
     for {