Allow lnd remote to work with certificate string (#3840)

lnd-rpc/src/main/scala/org/bitcoins/lnd/rpc/LndRpcClient.scala

@@ -43,7 +43,7 @@ import walletrpc.{
   _
 }
 
-import java.io.{File, FileInputStream}
+import java.io._
 import java.net.InetSocketAddress
 import java.util.concurrent.Executor
 import java.util.concurrent.atomic.AtomicInteger
@@ -76,8 +76,19 @@ class LndRpcClient(val instance: LndInstance, binaryOpt: Option[File] = None)(
 
   // These need to be lazy so we don't try and fetch
   // the tls certificate before it is generated
-
-  private[this] lazy val certStream = new FileInputStream(instance.certFile)
+  private[this] lazy val certStreamOpt: Option[InputStream] = {
+    instance.certFileOpt match {
+      case Some(file) => Some(new FileInputStream(file))
+      case None =>
+        instance.certificateOpt match {
+          case Some(cert) =>
+            Some(
+              new ByteArrayInputStream(
+                cert.getBytes(java.nio.charset.StandardCharsets.UTF_8.name)))
+          case None => None
+        }
+    }
+  }
 
   private lazy val callCredentials = new CallCredentials {
 
@@ -99,12 +110,22 @@ class LndRpcClient(val instance: LndInstance, binaryOpt: Option[File] = None)(
   }
 
   // Configure the client
-  private lazy val clientSettings: GrpcClientSettings =
-    GrpcClientSettings
+  private lazy val clientSettings: GrpcClientSettings = {
+    val trustManagerOpt = certStreamOpt match {
+      case Some(stream) => Some(SSLContextUtils.trustManagerFromStream(stream))
+      case None         => None
+    }
+
+    val client = GrpcClientSettings
       .connectToServiceAt(instance.rpcUri.getHost, instance.rpcUri.getPort)
-      .withTrustManager(SSLContextUtils.trustManagerFromStream(certStream))
       .withCallCredentials(callCredentials)
 
+    trustManagerOpt match {
+      case Some(trustManager) => client.withTrustManager(trustManager)
+      case None               => client
+    }
+  }
+
   // Create a client-side stub for the services
   lazy val lnd: LightningClient = LightningClient(clientSettings)
   lazy val wallet: WalletKitClient = WalletKitClient(clientSettings)

lnd-rpc/src/main/scala/org/bitcoins/lnd/rpc/config/LndInstance.scala

@@ -15,7 +15,8 @@ import scala.util.Properties
 sealed trait LndInstance {
   def rpcUri: URI
   def macaroon: String
-  def certFile: File
+  def certFileOpt: Option[File]
+  def certificateOpt: Option[String]
 }
 
 case class LndInstanceLocal(
@@ -30,6 +31,9 @@ case class LndInstanceLocal(
     debugLevel: LogLevel)
     extends LndInstance {
 
+  override val certificateOpt: Option[String] = None
+  override val certFileOpt: Option[File] = Some(certFile)
+
   private var macaroonOpt: Option[String] = None
 
   override def macaroon: String = {
@@ -98,5 +102,26 @@ object LndInstanceLocal
   }
 }
 
-case class LndInstanceRemote(rpcUri: URI, macaroon: String, certFile: File)
+case class LndInstanceRemote(
+    rpcUri: URI,
+    macaroon: String,
+    certFileOpt: Option[File],
+    certificateOpt: Option[String])
     extends LndInstance
+
+object LndInstanceRemote {
+
+  def apply(
+      rpcUri: URI,
+      macaroon: String,
+      certFile: File): LndInstanceRemote = {
+    LndInstanceRemote(rpcUri, macaroon, Some(certFile), None)
+  }
+
+  def apply(
+      rpcUri: URI,
+      macaroon: String,
+      certificate: String): LndInstanceRemote = {
+    LndInstanceRemote(rpcUri, macaroon, None, Some(certificate))
+  }
+}

testkit/src/main/scala/org/bitcoins/testkit/fixtures/LndFixture.scala

@@ -7,6 +7,8 @@ import org.bitcoins.testkit.lnd._
 import org.bitcoins.testkit.rpc._
 import org.scalatest.FutureOutcome
 
+import scala.io.Source
+
 /** A trait that is useful if you need Lnd fixtures for your test suite */
 trait LndFixture extends BitcoinSFixture with CachedBitcoindV21 {
 
@@ -82,10 +84,20 @@ trait RemoteLndFixture extends BitcoinSFixture with CachedBitcoindV21 {
           client = LndRpcTestClient.fromSbtDownload(Some(bitcoind))
           lnd <- client.start()
 
+          // get certificate as a string
+          cert = {
+            val file = lnd.instance.certFileOpt.get
+            val source = Source.fromFile(file)
+            val str = source.getLines().toVector.mkString("\n")
+            source.close()
+
+            str
+          }
+
           // create a remote instance and client
           remoteInstance = LndInstanceRemote(lnd.instance.rpcUri,
                                              lnd.instance.macaroon,
-                                             lnd.instance.certFile)
+                                             cert)
           remoteLnd = LndRpcClient(remoteInstance)
         } yield remoteLnd
       },