feat(dotnet,java): kernel process inherits host's STDERR

packages/@jsii/dotnet-runtime/src/Amazon.JSII.Runtime.UnitTests/Client/RuntimeTests.cs

@@ -11,17 +11,15 @@ public sealed class RuntimeTests
         private const string Prefix = "Runtime.";
 
         private INodeProcess _nodeProcessMock;
-        
+
         private IRuntime _sut;
 
         public RuntimeTests()
         {
             _nodeProcessMock = Substitute.For<INodeProcess>();
             var standardOutputMock = Substitute.For<TextReader>();
-            var standardErrorMock = Substitute.For<TextReader>();
 
             _nodeProcessMock.StandardOutput.Returns(standardOutputMock);
-            _nodeProcessMock.StandardError.Returns(standardErrorMock);
 
             _sut = new Services.Runtime(_nodeProcessMock);
         }
@@ -30,10 +28,9 @@ public RuntimeTests()
         public void ThrowsJsiiExceptionWhenResponseNotReceived()
         {
             _nodeProcessMock.StandardOutput.ReadLine().ReturnsNull();
-            _nodeProcessMock.StandardError.ReadToEnd().Returns("This is a test.");
 
             var ex = Assert.Throws<JsiiException>(() => _sut.ReadResponse());
-            Assert.Equal("Child process exited unexpectedly: This is a test.", ex.Message);
+            Assert.Equal("Child process exited unexpectedly!", ex.Message);
         }
     }
-}
+}

packages/@jsii/dotnet-runtime/src/Amazon.JSII.Runtime/Services/INodeProcess.cs

@@ -8,7 +8,5 @@ internal interface INodeProcess : IDisposable
         TextWriter StandardInput { get; }
 
         TextReader StandardOutput { get; }
-
-        TextReader StandardError { get; }
     }
 }

packages/@jsii/dotnet-runtime/src/Amazon.JSII.Runtime/Services/NodeProcess.cs

@@ -38,8 +38,7 @@ public NodeProcess(IJsiiRuntimeProvider jsiiRuntimeProvider, ILoggerFactory logg
                     StandardInputEncoding = utf8,
                     RedirectStandardOutput = true,
                     StandardOutputEncoding = utf8,
-                    RedirectStandardError = true,
-                    StandardErrorEncoding = utf8
+                    UseShellExecute = false,
                 }
             };
 
@@ -58,18 +57,23 @@ public NodeProcess(IJsiiRuntimeProvider jsiiRuntimeProvider, ILoggerFactory logg
             _process.Start();
         }
 
+        ~NodeProcess() {
+            ((IDisposable)this).Dispose();
+        }
+
         public TextWriter StandardInput => _process.StandardInput;
 
         public TextReader StandardOutput => _process.StandardOutput;
 
-        public TextReader StandardError => _process.StandardError;
-
         void IDisposable.Dispose()
         {
-            StandardInput.Dispose();
-            StandardOutput.Dispose();
-            StandardError.Dispose();
+            StandardInput.Close();
+            _process.WaitForExit(5_000);
             _process.Dispose();
+
+            // If Dispose() is called manually, there is no need to run the finalizer anymore, since
+            // this only calls Dispose(). So we inform the GC about this.
+            GC.SuppressFinalize(this);
         }
 
         /// <summary>

packages/@jsii/dotnet-runtime/src/Amazon.JSII.Runtime/Services/Runtime.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Threading.Tasks;
 
 namespace Amazon.JSII.Runtime.Services
 {
@@ -10,19 +9,14 @@ internal sealed class Runtime : IRuntime
         public Runtime(INodeProcess nodeProcess)
         {
             _nodeProcess = nodeProcess ?? throw new ArgumentNullException(nameof(nodeProcess));
-            if (Environment.GetEnvironmentVariable("JSII_DEBUG") != null)
-            {
-                Task.Run(() => RedirectStandardError());
-            }
         }
 
         public string ReadResponse()
         {
             var response = _nodeProcess.StandardOutput.ReadLine();
             if (string.IsNullOrEmpty(response))
             {
-                var errorMessage = _nodeProcess.StandardError.ReadToEnd();
-                throw new JsiiException("Child process exited unexpectedly: " + errorMessage);
+                throw new JsiiException("Child process exited unexpectedly!");
             }
 
             return response;
@@ -43,13 +37,5 @@ public void WriteRequest(string request)
             _nodeProcess.StandardInput.WriteLine(request);
             _nodeProcess.StandardInput.Flush();
         }
-
-        private void RedirectStandardError()
-        {
-            while (true)
-            {
-                Console.Error.WriteLine(_nodeProcess.StandardError.ReadLine());
-            }
-        }
     }
 }

packages/@jsii/java-runtime/project/src/main/java/software/amazon/jsii/JsiiRuntime.java

@@ -14,6 +14,7 @@
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
 import static software.amazon.jsii.JsiiVersion.JSII_RUNTIME_VERSION;
@@ -29,11 +30,6 @@ public final class JsiiRuntime {
      */
     private static final String VERSION_BUILD_PART_REGEX = "\\+[a-z0-9]+$";
 
-    /**
-     * True to print server traces to STDERR.
-     */
-    private static boolean traceEnabled = false;
-
     /**
      *
      */
@@ -49,11 +45,6 @@ public final class JsiiRuntime {
      */
     private Process childProcess;
 
-    /**
-     * Child's standard error.
-     */
-    private BufferedReader stderr;
-
     /**
      * Child's standard output.
      */
@@ -179,26 +170,23 @@ protected void finalize() throws Throwable {
     }
 
     public void terminate() throws InterruptedException, IOException {
-        if (stderr != null) {
-            stderr.close();
-            stderr = null;
-        }
-
-        if (stdout != null) {
-            stdout.close();
-            stdout = null;
-        }
-
-        if (stdin != null) {
+         if (stdin != null) {
             stdin.close();
             stdin = null;
         }
 
         if (childProcess != null) {
             // Wait for the child process to complete
-            childProcess.waitFor();
+            if (!childProcess.waitFor(5, TimeUnit.SECONDS)) {
+                childProcess.destroy();
+            }
             childProcess = null;
         }
+
+        if (stdout != null) {
+            stdout.close();
+            stdout = null;
+        }
     }
 
     /**
@@ -211,12 +199,10 @@ private void startRuntimeIfNeeded() {
 
         // If JSII_DEBUG is set, enable traces.
         String jsiiDebug = System.getenv("JSII_DEBUG");
-        if (jsiiDebug != null
+        boolean traceEnabled = jsiiDebug != null
                 && !jsiiDebug.isEmpty()
                 && !jsiiDebug.equalsIgnoreCase("false")
-                && !jsiiDebug.equalsIgnoreCase("0")) {
-            traceEnabled = true;
-        }
+                && !jsiiDebug.equalsIgnoreCase("0");
 
         // If JSII_RUNTIME is set, use it to find the jsii-server executable
         // otherwise, we default to "jsii-runtime" from PATH.
@@ -229,7 +215,10 @@ private void startRuntimeIfNeeded() {
             System.err.println("jsii-runtime: " + jsiiRuntimeExecutable);
         }
 
-        ProcessBuilder pb = new ProcessBuilder("node", jsiiRuntimeExecutable);
+        ProcessBuilder pb = new ProcessBuilder("node", jsiiRuntimeExecutable)
+            .redirectInput(ProcessBuilder.Redirect.PIPE)
+            .redirectOutput(ProcessBuilder.Redirect.PIPE)
+            .redirectError(ProcessBuilder.Redirect.INHERIT);
 
         if (traceEnabled) {
             pb.environment().put("JSII_DEBUG", "1");
@@ -245,21 +234,13 @@ private void startRuntimeIfNeeded() {
 
         OutputStreamWriter stdinStream = new OutputStreamWriter(this.childProcess.getOutputStream(), StandardCharsets.UTF_8);
         InputStreamReader stdoutStream = new InputStreamReader(this.childProcess.getInputStream(), StandardCharsets.UTF_8);
-        InputStreamReader stderrStream = new InputStreamReader(this.childProcess.getErrorStream(), StandardCharsets.UTF_8);
 
-        this.stderr = new BufferedReader(stderrStream);
         this.stdout = new BufferedReader(stdoutStream);
         this.stdin = new BufferedWriter(stdinStream);
 
         handshake();
 
         this.client = new JsiiClient(this);
-
-        // if trace is enabled, start a thread that continuously reads from the child process's
-        // STDERR and prints to my STDERR.
-        if (traceEnabled) {
-            startPipeErrorStreamThread();
-        }
     }
 
     /**
@@ -286,8 +267,7 @@ JsonNode readNextResponse() {
         try {
             String responseLine = this.stdout.readLine();
             if (responseLine == null) {
-                String error = this.stderr.lines().collect(Collectors.joining("\n\t"));
-                throw new JsiiException("Child process exited unexpectedly: " + error);
+                throw new JsiiException("Child process exited unexpectedly!");
             }
             final JsonNode response = JsiiObjectMapper.INSTANCE.readTree(responseLine);
             JsiiRuntime.notifyInspector(response, MessageInspector.MessageType.Response);
@@ -297,28 +277,6 @@ JsonNode readNextResponse() {
         }
     }
 
-    /**
-     * Starts a thread that pipes STDERR from the child process to our STDERR.
-     */
-    private void startPipeErrorStreamThread() {
-        Thread daemon = new Thread(() -> {
-            while (true) {
-                try {
-                    String line = stderr.readLine();
-                    System.err.println(line);
-                    if (line == null) {
-                        break;
-                    }
-                } catch (IOException e) {
-                    e.printStackTrace();
-                }
-            }
-        });
-
-        daemon.setDaemon(true);
-        daemon.start();
-    }
-
     /**
      * This will return the server process in case it is not already started.
      * @return A {@link JsiiClient} connected to the server process.
@@ -331,13 +289,6 @@ public JsiiClient getClient() {
         return this.client;
     }
 
-    /**
-     * Prints jsii-server traces to STDERR.
-     */
-    public static void enableTrace() {
-        traceEnabled = true;
-    }
-
     /**
      * Asserts that a peer runtimeVersion is compatible with this Java runtime version, which means
      * they share the same version components, with the possible exception of the build number.