Add clightning sendcustommsg (#3883)

app-commons/src/main/scala/org/bitcoins/commons/jsonmodels/clightning/CLightningJsonModels.scala

@@ -345,4 +345,8 @@ object CLightningJsonModels {
   case class ListTransactionsResults(
       transactions: Vector[CLightningTransaction]
   ) extends CLightningJsonModel
+
+  case class SendCustomMessageResult(
+      status: String
+  ) extends CLightningJsonModel
 }

app-commons/src/main/scala/org/bitcoins/commons/serializers/JsonSerializers.scala

@@ -705,6 +705,9 @@ object JsonSerializers {
     ListTransactionsResults] =
     Json.reads[ListTransactionsResults]
 
+  implicit val SendCustomMessageResultReads: Reads[SendCustomMessageResult] =
+    Json.reads[SendCustomMessageResult]
+
   implicit val byteVectorWrites: Writes[ByteVector] =
     Writes[ByteVector](bytes => JsString(bytes.toHex))
 

clightning-rpc-test/src/test/scala/com/bitcoins/clightning/rpc/CLightningClientPairTest.scala

@@ -2,6 +2,7 @@ package com.bitcoins.clightning.rpc
 
 import org.bitcoins.core.currency._
 import org.bitcoins.core.number._
+import org.bitcoins.core.protocol.BigSizeUInt
 import org.bitcoins.core.protocol.script.EmptyScriptSignature
 import org.bitcoins.core.protocol.transaction._
 import org.bitcoins.core.psbt.PSBT
@@ -9,6 +10,7 @@ import org.bitcoins.core.wallet.fee.SatoshisPerKW
 import org.bitcoins.testkit.async.TestAsyncUtil
 import org.bitcoins.testkit.clightning.CLightningRpcTestUtil
 import org.bitcoins.testkit.fixtures.DualCLightningFixture
+import scodec.bits._
 
 import scala.concurrent.Future
 import scala.concurrent.duration.DurationInt
@@ -160,4 +162,18 @@ class CLightningClientPairTest extends DualCLightningFixture {
       assert(newBalA === oldBalA - sendAmt - feeRate.calc(tx) +- Satoshis(200))
     }
   }
+
+  it must "send a custom message to another peer" in { params =>
+    val (_, clightningA, clightningB) = params
+
+    for {
+      nodeId <- clightningB.nodeId
+      result <- clightningA.sendCustomMessage(
+        nodeId,
+        BigSizeUInt(48001),
+        hex"000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f")
+    } yield {
+      assert(result.status.nonEmpty)
+    }
+  }
 }

clightning-rpc/src/main/scala/com/bitcoins/clightning/rpc/CLightningRpcClient.scala

@@ -8,16 +8,18 @@ import org.bitcoins.commons.serializers.JsonSerializers._
 import org.bitcoins.commons.util.NativeProcessFactory
 import org.bitcoins.core.currency.{CurrencyUnit, Satoshis}
 import org.bitcoins.core.hd.AddressType
-import org.bitcoins.core.protocol.BitcoinAddress
+import org.bitcoins.core.protocol._
 import org.bitcoins.core.protocol.ln.LnInvoice
 import org.bitcoins.core.protocol.ln.channel.{FundedChannelId, ShortChannelId}
 import org.bitcoins.core.protocol.ln.currency.MilliSatoshis
 import org.bitcoins.core.protocol.ln.node.{NodeId, NodeUri}
+import org.bitcoins.core.protocol.tlv._
 import org.bitcoins.core.psbt.PSBT
 import org.bitcoins.core.util.StartStopAsync
 import org.bitcoins.core.wallet.fee._
 import org.bitcoins.crypto.Sha256Digest
 import play.api.libs.json._
+import scodec.bits._
 
 import java.io.File
 import java.net.InetSocketAddress
@@ -326,6 +328,33 @@ class CLightningRpcClient(val instance: CLightningInstanceLocal, binary: File)(
     clightningCall[FundChannelCancelResult]("fundchannel_cancel", params)
   }
 
+  def sendCustomMessage(
+      peer: NodeId,
+      tpe: BigSizeUInt,
+      data: ByteVector): Future[SendCustomMessageResult] = {
+    val tlv = TLV.fromTypeAndValue(tpe, data)
+    sendCustomMessage(peer, tlv)
+  }
+
+  def sendCustomMessage(
+      peer: NodeId,
+      tlv: TLV): Future[SendCustomMessageResult] = {
+    val lnMessage = LnMessage[TLV](tlv)
+    sendCustomMessage(peer, lnMessage)
+  }
+
+  def sendCustomMessage(
+      peer: NodeId,
+      lnMessage: LnMessage[TLV]): Future[SendCustomMessageResult] = {
+    val params = JsObject(
+      Vector(
+        "node_id" -> JsString(peer.toString),
+        "msg" -> JsString(lnMessage.hex)
+      ))
+
+    clightningCall[SendCustomMessageResult]("sendcustommsg", params)
+  }
+
   override val cmd: String = {
     val logFileConf = instance.logFileOpt
       .map(f => s"--log-file=${f.getAbsolutePath}")