Fix displaying error dialog and logging errors (#1848)

elixirkit/demo/rel/appkit/Sources/Demo/Demo.swift

@@ -12,27 +12,37 @@ public struct Demo {
 }
 
 class AppDelegate: NSObject, NSApplicationDelegate {
-    private var window : NSWindow!
+    private var window: NSWindow!
+    private var button: NSButton!
 
     func applicationDidFinishLaunching(_ aNotification: Notification) {
+        button = NSButton(title: "Press me!", target: self, action: #selector(pressMe))
+        button.isEnabled = false
+
         ElixirKit.API.start(
             name: "demo",
+            readyHandler: {
+                // GUI updates need to happen on the main thread.
+                DispatchQueue.main.sync {
+                    self.button.isEnabled = true
+                }
+
+                ElixirKit.API.publish("log", "Hello from AppKit!")
+
+                ElixirKit.API.addObserver(queue: .main) { (name, data) in
+                    switch name {
+                    case "log":
+                        print("[client] " + data)
+                    default:
+                        fatalError("unknown event \(name)")
+                    }
+                }
+            },
             terminationHandler: { _ in
                 NSApp.terminate(nil)
             }
         )
 
-        ElixirKit.API.publish("log", "Hello from AppKit!")
-
-        ElixirKit.API.addObserver(queue: .main) { (name, data) in
-            switch name {
-            case "log":
-                print("[client] " + data)
-            default:
-                fatalError("unknown event \(name)")
-            }
-        }
-
         let menuItemOne = NSMenuItem()
         menuItemOne.submenu = NSMenu(title: "Demo")
         menuItemOne.submenu?.items = [
@@ -48,8 +58,6 @@ class AppDelegate: NSObject, NSApplicationDelegate {
                           defer: true)
         window.orderFrontRegardless()
         window.title = "Demo"
-
-        let button = NSButton(title: "Press me!", target: self, action: #selector(pressMe))
         window.contentView!.subviews.append(button)
 
         NSApp.setActivationPolicy(.regular)

elixirkit/demo/rel/dotnet/Demo.cs

@@ -2,22 +2,27 @@ class Demo
 {
     public static void Main()
     {
-        ElixirKit.API.Start(name: "demo");
+        ElixirKit.API.Start(
-        ElixirKit.API.Publish("log", "Hello from C#!");
+            name: "demo",
-
+            ready: () =>
-        ElixirKit.API.Subscribe((name, data) =>
-        {
-            switch (name)
             {
-                case "log":
+                ElixirKit.API.Publish("log", "Hello from C#!");
-                    Console.WriteLine($"[client] {data}");
-                    break;
 
-                default:
+                ElixirKit.API.Subscribe((name, data) =>
-                    throw new Exception($"unknown event {name}");
+                {
+                    switch (name)
+                    {
+                        case "log":
+                            Console.WriteLine($"[client] {data}");
+                            break;
+
+                        default:
+                            throw new Exception($"unknown event {name}");
+                    }
+                });
             }
-        });
+        );
 
-        ElixirKit.API.WaitForExit();
+        System.Console.WriteLine($"{ElixirKit.API.WaitForExit()}");
     }
 }

elixirkit/demo/rel/swift/Sources/Demo/Demo.swift

@@ -10,17 +10,21 @@ struct Demo {
             exit(signal)
         }
 
-        ElixirKit.API.start(name: "demo")
+        ElixirKit.API.start(
-        ElixirKit.API.publish("log", "Hello from Swift!")
+            name: "demo",
+            readyHandler: {
+                ElixirKit.API.publish("log", "Hello from Swift!")
 
-        ElixirKit.API.addObserver(queue: .main) { (name, data) in
+                ElixirKit.API.addObserver(queue: .main) { (name, data) in
-            switch name {
+                    switch name {
-            case "log":
+                    case "log":
-                print("[client] " + data)
+                        print("[client] " + data)
-            default:
+                    default:
-                fatalError("unknown event \(name)")
+                        fatalError("unknown event \(name)")
+                    }
+                }
             }
-        }
+        )
 
         ElixirKit.API.waitUntilExit()
     }

elixirkit/demo/rel/winforms/Demo.cs

@@ -7,31 +7,36 @@ static class DemoMain
     {
         if (ElixirKit.API.IsMainInstance("com.example.Demo"))
         {
-            ElixirKit.API.Start(name: "demo", exited: (exitCode) =>
+            ElixirKit.API.Start(
-            {
+                name: "demo",
-                Application.Exit();
+                ready: () =>
-            });
+                {
+                    ElixirKit.API.Publish("log", "Hello from Windows Forms!");
+
+                    ElixirKit.API.Subscribe((name, data) =>
+                    {
+                        switch (name)
+                        {
+                            case "log":
+                                Console.WriteLine($"[client] {data}");
+                                break;
+
+                            default:
+                                throw new Exception($"unknown event {name}");
+                        }
+                    });
+                },
+                exited: (exitCode) =>
+                {
+                    Application.Exit();
+                }
+            );
 
             Application.ApplicationExit += (sender, args) =>
             {
                 ElixirKit.API.Stop();
             };
 
-            ElixirKit.API.Publish("log", "Hello from Windows Forms!");
-
-            ElixirKit.API.Subscribe((name, data) =>
-            {
-                switch (name)
-                {
-                    case "log":
-                        Console.WriteLine($"[client] {data}");
-                        break;
-
-                    default:
-                        throw new Exception($"unknown event {name}");
-                }
-            });
-
             ApplicationConfiguration.Initialize();
             Application.Run(new DemoForm());
         }

elixirkit/elixirkit_dotnet/ElixirKit.cs

@@ -10,6 +10,8 @@ using System.Net.Sockets;
 
 namespace ElixirKit;
 
+public delegate void ReadyHandler();
+
 public delegate void ExitHandler(int ExitCode);
 
 public delegate void EventHandler(string Name, string Data);
@@ -43,11 +45,11 @@ public static class API
         }
     }
 
-    public static void Start(string name, ExitHandler? exited = null, string? logPath = null)
+    public static void Start(string name, ReadyHandler ready, ExitHandler? exited = null, string? logPath = null)
     {
         ensureMainInstance();
 
-        release = new Release(name, exited, logPath);
+        release = new Release(name, ready, exited, logPath);
 
         if (mutex != null)
         {
@@ -136,7 +138,7 @@ internal class Release
         }
     }
 
-    public Release(string name, ExitHandler? exited = null, string? logPath = null)
+    public Release(string name, ReadyHandler ready, ExitHandler? exited = null, string? logPath = null)
     {
         logger = new Logger(logPath);
         listener = new Listener();
@@ -187,8 +189,11 @@ internal class Release
         process.BeginOutputReadLine();
         process.BeginErrorReadLine();
 
-        var tcpClient = listener.TcpListener.AcceptTcpClient();
+        Task.Run(() => {
-        client = new Client(tcpClient);
+            var tcpClient = listener.TcpListener.AcceptTcpClient();
+            client = new Client(tcpClient);
+            ready();
+        });
     }
 
     public void Send(string message)

elixirkit/elixirkit_swift/Sources/ElixirKit/ElixirKit.swift

@@ -13,20 +13,25 @@ public class API {
         }
     }
 
-    public static func start(name: String, logPath: String? = nil, terminationHandler: ((Process) -> Void)? = nil) {
+    public static func start(
-        release = Release(name: name, logPath: logPath, terminationHandler: terminationHandler)
+        name: String,
+        logPath: String? = nil,
+        readyHandler: @escaping () -> Void,
+        terminationHandler: ((Process) -> Void)? = nil) {
+
+        release = Release(name: name, logPath: logPath, readyHandler: readyHandler, terminationHandler: terminationHandler)
     }
 
     public static func publish(_ name: String, _ data: String) {
-        release?.publish(name, data)
+        release!.publish(name, data)
     }
 
     public static func stop() {
-        release?.stop();
+        release!.stop();
     }
 
     public static func waitUntilExit() {
-        release?.waitUntilExit();
+        release!.waitUntilExit();
     }
 
     public static func addObserver(queue: OperationQueue?, using: @escaping (((String, String)) -> Void)) {
@@ -42,6 +47,7 @@ private class Release {
     let logger: Logger
     let listener: NWListener
     var connection: Connection?
+    let readyHandler: () -> Void
     let semaphore = DispatchSemaphore(value: 0)
 
     var isRunning: Bool {
@@ -50,7 +56,13 @@ private class Release {
         }
     }
 
-    init(name: String, logPath: String? = nil, terminationHandler: ((Process) -> Void)? = nil) {
+    init(
+        name: String,
+        logPath: String? = nil,
+        readyHandler: @escaping () -> Void,
+        terminationHandler: ((Process) -> Void)? = nil) {
+
+        self.readyHandler = readyHandler
         logger = Logger(logPath: logPath)
         listener = try! NWListener(using: .tcp, on: .any)
 
@@ -77,7 +89,7 @@ private class Release {
         listener.newConnectionHandler = didAccept(conn:)
         listener.start(queue: .global())
 
-        let seconds = 15
+        let seconds = 5
         let timeout = DispatchTime.now() + DispatchTimeInterval.seconds(seconds)
 
         if semaphore.wait(timeout: timeout) == .timedOut {
@@ -86,7 +98,7 @@ private class Release {
     }
 
     public func stop() {
-        connection!.cancel()
+        connection?.cancel()
         listener.cancel()
         waitUntilExit()
     }
@@ -117,11 +129,12 @@ private class Release {
         env["ELIXIRKIT_PORT"] = port
         process.environment = env
         try! process.run()
+        semaphore.signal()
     }
 
     private func didAccept(conn: NWConnection) {
         self.connection = Connection(conn: conn, logger: logger)
-        semaphore.signal()
+        readyHandler()
     }
 }
 

rel/app/macos/Sources/Livebook/Livebook.swift

@@ -21,35 +21,40 @@ class AppDelegate: NSObject, NSApplicationDelegate {
     func applicationDidFinishLaunching(_ aNotification: Notification) {
         logPath = "\(NSHomeDirectory())/Library/Logs/Livebook.log"
 
-        ElixirKit.API.start(name: "app", logPath: logPath) { process in
+        ElixirKit.API.start(
-            if process.terminationStatus != 0 {
+            name: "app",
-                DispatchQueue.main.sync {
+            logPath: logPath,
-                    let alert = NSAlert()
+            readyHandler: {
-                    alert.alertStyle = .critical
+                if (self.initialURLs == []) {
-                    alert.messageText = "Livebook exited with error status \(process.terminationStatus)"
+                    ElixirKit.API.publish("open", "")
-                    alert.addButton(withTitle: "Dismiss")
+                }
-                    alert.addButton(withTitle: "View Logs")
+                else {
-
+                    for url in self.initialURLs {
-                    switch alert.runModal() {
+                        ElixirKit.API.publish("open", url.absoluteString)
-                    case .alertSecondButtonReturn:
-                        self.viewLogs()
-                    default:
-                        ()
                     }
                 }
-            }
+            },
+            terminationHandler: { process in
+                if process.terminationStatus != 0 {
+                    DispatchQueue.main.sync {
+                        let alert = NSAlert()
+                        alert.alertStyle = .critical
+                        alert.messageText = "Livebook exited with error status \(process.terminationStatus)"
+                        alert.addButton(withTitle: "Dismiss")
+                        alert.addButton(withTitle: "View Logs")
 
-            NSApp.terminate(nil)
+                        switch alert.runModal() {
-        }
+                        case .alertSecondButtonReturn:
+                            self.viewLogs()
+                        default:
+                            ()
+                        }
+                    }
+                }
 
-        if (self.initialURLs == []) {
+                NSApp.terminate(nil)
-            ElixirKit.API.publish("open", "")
-        }
-        else {
-            for url in self.initialURLs {
-                ElixirKit.API.publish("open", url.absoluteString)
             }
-        }
+        )
 
         statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.variableLength)
         let button = statusItem.button!
@@ -81,7 +86,6 @@ class AppDelegate: NSObject, NSApplicationDelegate {
                 fatalError("unknown event \(name)")
             }
         }
-
     }
 
     func applicationWillTerminate(_ aNotification: Notification) {

rel/app/windows/Livebook.cs

@@ -88,27 +88,28 @@ class LivebookApp : ApplicationContext
         ElixirKit.API.Start(
             name: "app",
             logPath: logPath,
+            ready: () => {
+                ElixirKit.API.Subscribe((name, data) =>
+                {
+                    switch (name)
+                    {
+                        case "url":
+                            copyURLButton.Enabled = true;
+                            this.url = data;
+                            break;
+
+                        default:
+                            throw new Exception($"unknown event {name}");
+                    }
+                });
+
+                ElixirKit.API.Publish("open", url);
+            },
             exited: (exitCode) =>
             {
                 Application.Exit();
             }
         );
-
-        ElixirKit.API.Subscribe((name, data) =>
-        {
-            switch (name)
-            {
-                case "url":
-                    copyURLButton.Enabled = true;
-                    this.url = data;
-                    break;
-
-                default:
-                    throw new Exception($"unknown event {name}");
-            }
-        });
-
-        ElixirKit.API.Publish("open", url);
     }
 
     private void threadExit(object? sender, EventArgs e)