Exit BspServerApp cleanly (#13)

* Resolved issue where bsp-server wasn't shutting down cleanly.

build.sbt

@@ -7,8 +7,8 @@ lazy val root = project
   .in(file("."))
   .settings(
     name := "bazel-bsp",
-    organization := "org.afenton",
-    version := "0.1.0-SNAPSHOT",
+    organization := "afenton",
+    version := "0.0.15",
     scalaVersion := scala3Version,
     libraryDependencies += "org.typelevel" %% "cats-effect" % "3.4.4",
     libraryDependencies += "co.fs2" %% "fs2-core" % "3.3.0",

examples/simple-no-errors/.bsp/bazel-bsp.json

@@ -7,6 +7,7 @@
         "scala"
     ],
     "argv": [
-        "bazel-bsp"
+        "../../target/universal/stage/bin/bazel-bsp",
+        "--verbose"
     ]
 }

examples/simple-with-errors/.bsp/bazel-bsp.json

@@ -7,6 +7,7 @@
         "scala"
     ],
     "argv": [
-        "bazel-bsp"
+        "../../target/universal/stage/bin/bazel-bsp",
+        "--verbose"
     ]
 }

src/main/scala/afenton/bazel/bsp/BazelBspApp.scala

@@ -24,6 +24,7 @@ import fs2.text
 import io.bazel.rules_scala.diagnostics.diagnostics.FileDiagnostics
 import io.circe.Json
 import io.circe.syntax.*
+import cats.effect.std.Console
 
 import java.net.ServerSocket
 import java.nio.file.Path
@@ -32,6 +33,7 @@ import cats.data.Nested
 import java.nio.file.StandardOpenOption
 import scala.concurrent.duration.FiniteDuration
 import java.util.concurrent.TimeUnit
+import cats.effect.kernel.Deferred
 
 object BazelBspApp
     extends CommandIOApp(
@@ -50,14 +52,14 @@ object BazelBspApp
           fs2.text.utf8.encode.andThen(fs2.io.stdout),
           fs2.text.utf8.encode.andThen(fs2.io.stderr)
         )
-        .handleErrorWith { e =>
-          IO.blocking {
-            System.err.println(
-              s"ERROR: 💣 💣 💣 \n${e.toString} \n${e.getStackTrace.mkString("\n")}"
-            )
-            ExitCode.Error
+          .handleErrorWith { e =>
+            IO.blocking {
+              System.err.println(
+                s"ERROR: 💣 💣 💣 \n${e.toString} \n${e.getStackTrace.mkString("\n")}"
+              )
+              ExitCode.Error
+            }
           }
-        }
       }
 
   val verifySetupOpt =
@@ -87,11 +89,11 @@ object BazelBspApp
   def printVerifyResult(
       result: List[(String, Either[String, Unit])]
   ): IO[Unit] =
-      result
-        .traverse_ {
-          case (n, Right(_))  => IO.println(s"✅ $n")
-          case (n, Left(err)) => IO.println(s"❌ $n\n   $err\n")
-        }
+    result
+      .traverse_ {
+        case (n, Right(_))  => IO.println(s"✅ $n")
+        case (n, Left(err)) => IO.println(s"❌ $n\n   $err\n")
+      }
 
   def main: Opts[IO[ExitCode]] =
     verboseOpt
@@ -140,14 +142,13 @@ object BazelBspApp
       logger: Logger
   ): Stream[IO, Unit] =
     inStream
-      // .evalTap(s => logger.trace(s))
       .through(jRpcParser(logger))
       .evalTap(request => logger.trace(s"request: ${request}"))
       .through(messageDispatcher(BspServer.jsonRpcRouter(bspServer)))
       .evalTap(response => logger.trace(s"response: ${response}"))
       .evalMap {
         case resp: Response => outQ.offer(resp)
-        case u: Unit => IO.unit
+        case u: Unit        => IO.unit
       }
 
   private def processOutStream(
@@ -158,7 +159,6 @@ object BazelBspApp
     Stream
       .fromQueueUnterminated(outQ, 100)
       .map(msg => JRpcConsoleCodec.encode(msg, false))
-      // .evalTap(msg => logger.trace(msg))
       .through(outPipe)
 
   def server(verbose: Boolean)(
@@ -177,5 +177,8 @@ object BazelBspApp
         processOutStream(outPipe, outQ, logger),
         logStream
       ).parJoin(3)
+        // NB: Allow time for response to get through
+        .interruptWhen(server.exitSignal)
+        .onFinalize(Console[IO].errorln("👋 BSP Server Shutting Down"))
       _ <- all.compile.drain
-    yield ExitCode.Success
+    yield ExitCode.Success

src/main/scala/afenton/bazel/bsp/BazelBspServer.scala

@@ -19,13 +19,15 @@ import io.circe.syntax._
 import java.net.URI
 import java.nio.file.Path
 import java.nio.file.Paths
+import cats.effect.kernel.Deferred
 
 import IOLifts.{asIO, mapToIO}
 
 class BazelBspServer(
     client: BspClient,
     logger: Logger,
-    stateRef: Ref[IO, BazelBspServer.ServerState]
+    stateRef: Ref[IO, BazelBspServer.ServerState],
+    val exitSignal: Deferred[IO, Either[Throwable, Unit]]
 ) extends BspServer(client):
 
   def buildInitialize(
@@ -252,7 +254,7 @@ class BazelBspServer(
   def buildExit(params: Unit): IO[Unit] =
     for
       _ <- logger.info("build/exit")
-      _ <- IO.canceled
+      _ <- exitSignal.complete(Right(()))
     yield ()
 
   private def doBuildTargetSources(
@@ -330,10 +332,11 @@ object BazelBspServer:
     ServerState(BazelBspServer.TargetSourceMap.empty, Nil, None, None, Nil)
 
   def create(client: BspClient, logger: Logger): IO[BazelBspServer] =
-    Ref.of[IO, BazelBspServer.ServerState](defaultState)
-      .map { stateRef =>
-        BazelBspServer(client, logger, stateRef)
-      }
+    for 
+      exitSwitch <- Deferred[IO, Either[Throwable, Unit]]
+      stateRef <- Ref.of[IO, BazelBspServer.ServerState](defaultState)
+    yield
+      BazelBspServer(client, logger, stateRef, exitSwitch)
 
   protected case class TargetSourceMap(
       val _targetSources: Map[BuildTargetIdentifier, List[

src/main/scala/afenton/bazel/bsp/BuildMetaData.scala

@@ -1,6 +1,6 @@
 package afenton.bazel.bsp
 
 object BuildMetaData {
-  val Version = "0.0.13"
+  val Version = "0.0.15"
   val BspVersion = "2.0.0-M2"
 }

src/test/scala/afenton/bazel/bsp/End2EndTest.scala

@@ -23,7 +23,8 @@ import scala.concurrent.duration._
 
 class End2EndTest extends munit.CatsEffectSuite with BspHelpers:
 
-  override val munitTimeout = 6.minute
+  // Long, because Github actions can run slooooow at times 
+  override val munitTimeout = 10.minute
 
   val projectRoot = Paths.get("").toAbsolutePath
 

src/test/scala/afenton/bazel/bsp/LspTestProcess.scala

@@ -46,6 +46,12 @@ case class BspClient(
     bspInQ: Queue[IO, String],
     counter: Ref[IO, Int]
 ):
+  private def sendNotification[A: Encoder](
+      method: String,
+      params: A
+  ): IO[Unit] =
+    val notification = Notification("2.0", method, Some(Encoder[A].apply(params)))
+    bspInQ.offer(JRpcConsoleCodec.encode(notification, false))
 
   private def sendRequest[A: Encoder, B: Decoder](
       method: String,
@@ -92,9 +98,8 @@ case class BspClient(
   def buildShutdown(params: Unit): IO[DeferredSource[IO, Unit]] =
     sendRequest("build/shutdown", params)
 
-  // TODO: Need to turn this into a notification, not a request
-  // def buildExit(params: Unit): IO[Unit] =
-  //   sendRequest("build/exit", params)
+  def buildExit(params: Unit): IO[Unit] =
+    sendNotification("build/exit", params)
 
   // def workspaceBuildTargets(params: Unit): IO[WorkspaceBuildTargetsResult]
 
@@ -261,9 +266,7 @@ case class LspTestProcess(workspaceRoot: Path):
     for
       d1 <- client.buildShutdown(())
       _ <- d1.get
-      // TODO need to send exit, once that's supported
-      // d2 <- client.buildExit(())
-      // _ <- d2.get
+      _ <- client.buildExit(())
       _ <- exitSwitch.complete(Right(()))
     yield ()