Revert "Launch multiple threads for worker processes"

This reverts commit b872dac.

rules/private/phases/phase_zinc_compile.bzl

@@ -88,7 +88,7 @@ def phase_zinc_compile(ctx, g):
         outputs = outputs,
         executable = worker.files_to_run.executable,
         input_manifests = input_manifests,
-        execution_requirements = _resolve_execution_reqs(ctx, {"no-sandbox": "1", "supports-multiplex-workers": "1"}),
+        execution_requirements = _resolve_execution_reqs(ctx, {"no-sandbox": "1", "supports-workers": "1"}),
         arguments = [args],
     )
 

rules/scala_proto/private/ScalaProtoWorker.scala

@@ -2,7 +2,7 @@ package annex.scala.proto
 
 import higherkindness.rules_scala.common.args.implicits._
 import higherkindness.rules_scala.common.worker.WorkerMain
-import java.io.{File, PrintStream}
+import java.io.File
 import java.nio.file.{Files, Paths}
 import java.util.Collections
 import net.sourceforge.argparse4j.ArgumentParsers
@@ -33,7 +33,7 @@ object ScalaProtoWorker extends WorkerMain[Unit] {
 
   override def init(args: Option[Array[String]]): Unit = ()
 
-  protected[this] def work(ctx: Unit, args: Array[String], out: PrintStream): Unit = {
+  protected[this] def work(ctx: Unit, args: Array[String]): Unit = {
     val namespace = argParser.parseArgs(args)
     val sources = namespace.getList[File]("sources").asScala.toList
 

rules/scalafmt/private/test.bzl

@@ -52,7 +52,7 @@ def build_format(ctx):
                 input_manifests = runner_manifests,
                 inputs = [ctx.file.config, src],
                 tools = runner_inputs,
-                execution_requirements = _resolve_execution_reqs(ctx, {"supports-multiplex-workers": "1"}),
+                execution_requirements = _resolve_execution_reqs(ctx, {"supports-workers": "1"}),
                 mnemonic = "ScalaFmt",
             )
             manifest_content.append("{} {}".format(src.short_path, file.short_path))

rules/scalafmt/scalafmt/ScalafmtRunner.scala

@@ -2,7 +2,7 @@ package annex.scalafmt
 
 import higherkindness.rules_scala.common.worker.WorkerMain
 import higherkindness.rules_scala.workers.common.Color
-import java.io.{File, PrintStream}
+import java.io.File
 import java.nio.file.Files
 import net.sourceforge.argparse4j.ArgumentParsers
 import net.sourceforge.argparse4j.impl.Arguments
@@ -16,7 +16,7 @@ object ScalafmtRunner extends WorkerMain[Unit] {
 
   protected[this] def init(args: Option[Array[String]]): Unit = {}
 
-  protected[this] def work(worker: Unit, args: Array[String], out: PrintStream): Unit = {
+  protected[this] def work(worker: Unit, args: Array[String]): Unit = {
 
     val parser = ArgumentParsers.newFor("scalafmt").addHelp(true).defaultFormatWidth(80).fromFilePrefix("@").build
     parser.addArgument("--config").required(true).`type`(Arguments.fileType)

src/main/scala/higherkindness/rules_scala/common/worker/WorkerMain.scala

@@ -8,21 +8,16 @@ import java.io.InputStream
 import java.io.PrintStream
 import java.lang.SecurityManager
 import java.security.Permission
-import java.util.concurrent.Executors
 import scala.annotation.tailrec
-import scala.concurrent.ExecutionContext.Implicits.global
-import scala.concurrent.Future
 import scala.util.control.NonFatal
-import scala.util.Success
-import scala.util.Failure
 
 trait WorkerMain[S] {
 
   private[this] final case class ExitTrapped(code: Int) extends Throwable
 
   protected[this] def init(args: Option[Array[String]]): S
 
-  protected[this] def work(ctx: S, args: Array[String], out: PrintStream): Unit
+  protected[this] def work(ctx: S, args: Array[String]): Unit
 
   final def main(args: Array[String]): Unit = {
     args.toList match {
@@ -41,62 +36,39 @@ trait WorkerMain[S] {
           }
         })
 
-        val garbageOut = new PrintStream(new ByteArrayOutputStream)
+        val outStream = new ByteArrayOutputStream
+        val out = new PrintStream(outStream)
 
         System.setIn(new ByteArrayInputStream(Array.emptyByteArray))
-        System.setOut(garbageOut)
-        System.setErr(garbageOut)
+        System.setOut(out)
+        System.setErr(out)
 
         try {
           @tailrec
           def process(ctx: S): S = {
             val request = WorkerProtocol.WorkRequest.parseDelimitedFrom(stdin)
             val args = request.getArgumentsList.toArray(Array.empty[String])
 
-            val outStream = new ByteArrayOutputStream
-            val out = new PrintStream(outStream)
-            val requestId = request.getRequestId()
-
-            val f: Future[Int] = Future {
+            val code =
               try {
-                work(ctx, args, out)
+                work(ctx, args)
                 0
               } catch {
                 case ExitTrapped(code) => code
                 case NonFatal(e) =>
-                  e.printStackTrace(out)
+                  e.printStackTrace()
                   1
               }
-            }
 
-            f.onComplete {
-              case Success(code) =>
-                synchronized {
-
-                  WorkerProtocol.WorkResponse.newBuilder
-                    .setRequestId(requestId)
-                    .setOutput(outStream.toString)
-                    .setExitCode(code)
-                    .build
-                    .writeDelimitedTo(stdout)
-
-                  out.flush()
-                  outStream.reset()
-                }
-              case Failure(e) => {
-                e.printStackTrace(out)
-
-                WorkerProtocol.WorkResponse.newBuilder
-                  .setRequestId(requestId)
-                  .setOutput(outStream.toString)
-                  .setExitCode(-1)
-                  .build
-                  .writeDelimitedTo(stdout)
-
-                out.flush()
-                outStream.reset()
-              }
-            }
+            WorkerProtocol.WorkResponse.newBuilder
+              .setOutput(outStream.toString)
+              .setExitCode(code)
+              .build
+              .writeDelimitedTo(stdout)
+
+            out.flush()
+            outStream.reset()
+
             process(ctx)
           }
           process(init(Some(args.toArray)))
@@ -106,11 +78,8 @@ trait WorkerMain[S] {
           System.setErr(stderr)
         }
 
-      case args => {
-        val outStream = new ByteArrayOutputStream
-        val out = new PrintStream(outStream)
-        work(init(None), args.toArray, out)
-      }
+      case args => work(init(None), args.toArray)
     }
   }
+
 }

src/main/scala/higherkindness/rules_scala/workers/bloop/compile/BloopRunner.scala

@@ -4,9 +4,8 @@ package workers.bloop.compile
 import common.worker.WorkerMain
 
 import bloop.Bloop
-import java.io.PrintStream
 
 object BloopRunner extends WorkerMain[Unit] {
   override def init(args: Option[Array[String]]): Unit = ()
-  override def work(ctx: Unit, args: Array[String], out: PrintStream): Unit = Bloop
+  override def work(ctx: Unit, args: Array[String]): Unit = Bloop
 }

src/main/scala/higherkindness/rules_scala/workers/common/AnnexLogger.scala

@@ -3,43 +3,44 @@ package workers.common
 
 import xsbti.Logger
 
-import java.io.{PrintStream, PrintWriter, StringWriter}
+import java.io.PrintWriter
+import java.io.StringWriter
 import java.nio.file.Paths
 import java.util.function.Supplier
 
 import CommonArguments.LogLevel
 
-final class AnnexLogger(level: String, out: PrintStream = System.err) extends Logger {
+final class AnnexLogger(level: String) extends Logger {
 
   private[this] val root = s"${Paths.get("").toAbsolutePath}/"
 
   private[this] def format(value: String): String = value.replace(root, "")
 
   def debug(msg: Supplier[String]): Unit = level match {
-    case LogLevel.Debug => out.println(format(msg.get))
+    case LogLevel.Debug => System.err.println(format(msg.get))
     case _              =>
   }
 
   def error(msg: Supplier[String]): Unit = level match {
-    case LogLevel.Debug | LogLevel.Error | LogLevel.Info | LogLevel.Warn => out.println(format(msg.get))
+    case LogLevel.Debug | LogLevel.Error | LogLevel.Info | LogLevel.Warn => System.err.println(format(msg.get))
     case _                                                               =>
   }
 
   def info(msg: Supplier[String]): Unit = level match {
-    case LogLevel.Debug | LogLevel.Info => out.println(format(msg.get))
+    case LogLevel.Debug | LogLevel.Info => System.err.println(format(msg.get))
     case _                              =>
   }
 
   def trace(err: Supplier[Throwable]): Unit = level match {
     case LogLevel.Debug | LogLevel.Error | LogLevel.Info | LogLevel.Warn =>
       val trace = new StringWriter();
       err.get.printStackTrace(new PrintWriter(trace));
-      out.println(format(trace.toString))
+      println(format(trace.toString))
     case _ =>
   }
 
   def warn(msg: Supplier[String]): Unit = level match {
-    case LogLevel.Debug | LogLevel.Info | LogLevel.Warn => out.println(format(msg.get))
+    case LogLevel.Debug | LogLevel.Info | LogLevel.Warn => System.err.println(format(msg.get))
     case _                                              =>
   }
 

src/main/scala/higherkindness/rules_scala/workers/deps/DepsRunner.scala

@@ -4,7 +4,7 @@ package workers.deps
 import common.args.implicits._
 import common.worker.WorkerMain
 
-import java.io.{File, PrintStream}
+import java.io.File
 import java.nio.file.{FileAlreadyExistsException, Files}
 import java.util.Collections
 import net.sourceforge.argparse4j.ArgumentParsers
@@ -48,7 +48,7 @@ object DepsRunner extends WorkerMain[Unit] {
 
   override def init(args: Option[Array[String]]): Unit = ()
 
-  override def work(ctx: Unit, args: Array[String], out: PrintStream): Unit = {
+  override def work(ctx: Unit, args: Array[String]): Unit = {
     val namespace = argParser.parseArgs(args)
 
     val label = namespace.getString("label").tail
@@ -64,9 +64,9 @@ object DepsRunner extends WorkerMain[Unit] {
       (directLabels -- usedWhitelist).filterNot(labelToPaths(_).exists(usedPaths))
     } else Nil
     remove.foreach { depLabel =>
-      out.println(s"Target '$depLabel' not used, please remove it from the deps.")
-      out.println(s"You can use the following buildozer command:")
-      out.println(s"buildozer 'remove deps $depLabel' $label")
+      println(s"Target '$depLabel' not used, please remove it from the deps.")
+      println(s"You can use the following buildozer command:")
+      println(s"buildozer 'remove deps $depLabel' $label")
     }
 
     val add = if (namespace.getBoolean("check_direct") == true) {
@@ -80,9 +80,9 @@ object DepsRunner extends WorkerMain[Unit] {
         )
     } else Nil
     add.foreach { depLabel =>
-      out.println(s"Target '$depLabel' is used but isn't explicitly declared, please add it to the deps.")
-      out.println(s"You can use the following buildozer command:")
-      out.println(s"buildozer 'add deps $depLabel' $label")
+      println(s"Target '$depLabel' is used but isn't explicitly declared, please add it to the deps.")
+      println(s"You can use the following buildozer command:")
+      println(s"buildozer 'add deps $depLabel' $label")
     }
 
     if (add.isEmpty && remove.isEmpty) {

src/main/scala/higherkindness/rules_scala/workers/zinc/compile/ZincRunner.scala

@@ -8,7 +8,7 @@ import workers.common.FileUtil
 import workers.common.LoggedReporter
 import common.worker.WorkerMain
 import com.google.devtools.build.buildjar.jarhelper.JarCreator
-import java.io.{File, PrintStream, PrintWriter}
+import java.io.{File, PrintWriter}
 import java.net.URLClassLoader
 import java.nio.file.{Files, NoSuchFileException, Path, Paths}
 import java.text.SimpleDateFormat
@@ -80,7 +80,7 @@ object ZincRunner extends WorkerMain[Namespace] {
     Paths.get(dir.replace("~", sys.props.getOrElse("user.home", "")))
   }
 
-  protected[this] def work(worker: Namespace, args: Array[String], out: PrintStream) = {
+  protected[this] def work(worker: Namespace, args: Array[String]) = {
     val usePersistence: Boolean = worker.getBoolean("use_persistence") match {
       case p: java.lang.Boolean => p
       case _                    => true
@@ -94,7 +94,7 @@ object ZincRunner extends WorkerMain[Namespace] {
 
     val depsCache = pathFrom(worker, "extracted_file_cache")
 
-    val logger = new AnnexLogger(namespace.getString("log_level"), out)
+    val logger = new AnnexLogger(namespace.getString("log_level"))
 
     val tmpDir = namespace.get[File]("tmp").toPath
 

src/main/scala/higherkindness/rules_scala/workers/zinc/doc/DocRunner.scala

@@ -8,7 +8,7 @@ import workers.common.AnnexScalaInstance
 import workers.common.CommonArguments.LogLevel
 import workers.common.FileUtil
 
-import java.io.{File, PrintStream}
+import java.io.File
 import java.net.URLClassLoader
 import java.nio.file.{Files, NoSuchFileException}
 import java.util.{Collections, Optional, Properties}
@@ -85,7 +85,7 @@ object DocRunner extends WorkerMain[Unit] {
 
   override def init(args: Option[Array[String]]): Unit = ()
 
-  override def work(ctx: Unit, args: Array[String], out: PrintStream): Unit = {
+  override def work(ctx: Unit, args: Array[String]): Unit = {
     val namespace = parser.parseArgsOrFail(args)
 
     val tmpDir = namespace.get[File]("tmp").toPath

third_party/bazel/src/main/protobuf/worker_protocol.proto

@@ -38,8 +38,6 @@ message WorkRequest {
   // The inputs that the worker is allowed to read during execution of this
   // request.
   repeated Input inputs = 2;
-
-  int32 request_id = 3;
 }
 
 // The worker sends this message to Blaze when it finished its work on the WorkRequest message.
@@ -50,6 +48,4 @@ message WorkResponse {
   // compiler warnings / errors etc. - thus we'll use a string type here, which gives us UTF-8
   // encoding.
   string output = 2;
-
-  int32 request_id = 3;
 }