Add connection selftest

src/main/java/mpo/dayon/assistant/gui/Assistant.java

@@ -51,6 +51,7 @@
 import static java.lang.String.valueOf;
 import static javax.swing.SwingConstants.HORIZONTAL;
 import static mpo.dayon.common.babylon.Babylon.translate;
+import static mpo.dayon.common.configuration.Configuration.DEFAULT_TOKEN_SERVER_URL;
 import static mpo.dayon.common.gui.common.ImageUtilities.getOrCreateIcon;
 import static mpo.dayon.common.utils.SystemUtilities.*;
 
@@ -250,17 +251,6 @@ public void actionPerformed(ActionEvent ev) {
                 final Point toolbarLocation = frame.getToolBar().getLocationOnScreen();
                 choices.setLocation(frameLocation.x + 20, toolbarLocation.y + frame.getToolBar().getHeight());
             }
-
-            private void resolvePublicIp() throws IOException, InterruptedException {
-                // HttpClient doesn't implement AutoCloseable nor close before Java 21!
-                @java.lang.SuppressWarnings("squid:S2095")
-                HttpClient client = HttpClient.newHttpClient();
-                HttpRequest request = HttpRequest.newBuilder()
-                        .uri(URI.create(WHATSMYIP_SERVER_URL))
-                        .timeout(Duration.ofSeconds(5))
-                        .build();
-                publicIp = client.send(request, HttpResponse.BodyHandlers.ofString()).body().trim();
-            }
         };
         ip.putValue("DISPLAY_NAME", publicIp); // always a selection
         // ...
@@ -269,6 +259,17 @@ private void resolvePublicIp() throws IOException, InterruptedException {
         return ip;
     }
 
+    private void resolvePublicIp() throws IOException, InterruptedException {
+        // HttpClient doesn't implement AutoCloseable nor close before Java 21!
+        @java.lang.SuppressWarnings("squid:S2095")
+        HttpClient client = HttpClient.newHttpClient();
+        HttpRequest request = HttpRequest.newBuilder()
+                .uri(URI.create(WHATSMYIP_SERVER_URL))
+                .timeout(Duration.ofSeconds(5))
+                .build();
+        publicIp = client.send(request, HttpResponse.BodyHandlers.ofString()).body().trim();
+    }
+
     private JMenuItem getJMenuItemCopyIpAndPort(JButton button) {
         final JMenuItem menuItem = new JMenuItem(translate("copy.msg"));
         menuItem.addActionListener(ev12 -> {
@@ -563,6 +564,7 @@ public void actionPerformed(ActionEvent ev) {
                         return token;
                     }).thenAcceptAsync(tokenString -> {
                         if (tokenString  != null) {
+                            token = tokenString;
                             button.setText(format(" %s", tokenString));
                             button.setToolTipText(translate("token.copy.msg"));
                         }
@@ -684,6 +686,19 @@ protected String doInBackground() {
 
         private void startNetwork() {
             frame.onGettingReady();
+            if (publicIp == null) {
+                try {
+                    resolvePublicIp();
+                } catch (IOException | InterruptedException ex) {
+                    Log.error("Could not determine public IP", ex);
+                    if (ex instanceof InterruptedException) {
+                        Thread.currentThread().interrupt();
+                    }
+                }
+            }
+            if (!networkEngine.selfTest(publicIp)) {
+                JOptionPane.showMessageDialog(frame, translate("port.error.msg1", networkConfiguration.getPort()), translate("port.error"), JOptionPane.WARNING_MESSAGE);
+            }
             networkEngine.start(compatibilityModeActive.get());
         }
 

src/main/java/mpo/dayon/assistant/network/NetworkAssistantEngine.java

@@ -19,6 +19,8 @@
 import java.awt.datatransfer.ClipboardOwner;
 import java.awt.datatransfer.DataFlavor;
 import java.io.*;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
 import java.net.Socket;
 import java.security.KeyManagementException;
 import java.security.NoSuchAlgorithmException;
@@ -66,14 +68,32 @@ public void addListener(NetworkAssistantEngineListener listener) {
         listeners.add(listener);
     }
 
+    public boolean selfTest(String publicIp) {
+        if (publicIp == null) {
+            return false;
+        }
+        if (!manageRouterPorts(0, configuration.getPort())) {
+            try (ServerSocket listener = new ServerSocket(configuration.getPort())) {
+                try (Socket socket = new Socket()) {
+                    socket.connect(new InetSocketAddress(publicIp, configuration.getPort()), 1000);
+                }
+                Log.info("Port " + configuration.getPort() + " is reachable from the outside");
+            } catch (IOException e) {
+                Log.error("Port " + configuration.getPort() + " is not reachable from the outside");
+                return false;
+            }
+        }
+        return true;
+    }
+
     /**
      * Called from a GUI action => do not block the AWT thread (!)
      */
     public void start(boolean compatibilityMode) {
         if (cancelling.get() || receiver != null) {
             return;
         }
-        manageRouterPorts(0, configuration.getPort());
+
         receiver = new Thread(new RunnableEx() {
             @Override
             protected void doRun() throws NoSuchAlgorithmException, KeyManagementException {
@@ -93,9 +113,9 @@ public void cancel() {
         fireOnDisconnecting();
     }
 
-    public static void manageRouterPorts(int oldPort, int newPort) {
+    public static boolean manageRouterPorts(int oldPort, int newPort) {
         if (!UPnP.isUPnPAvailable()) {
-            return;
+            return false;
         }
         if (oldPort != 0 && UPnP.isMappedTCP(oldPort)) {
             UPnP.closePortTCP(oldPort);
@@ -104,10 +124,12 @@ public static void manageRouterPorts(int oldPort, int newPort) {
         if (!UPnP.isMappedTCP(newPort)) {
             if (UPnP.openPortTCP(newPort, APP_NAME)) {
                 Log.info(format("Enabled forwarding for port %d", newPort));
-                return;
+                return true;
             }
             Log.warn(format("Failed to enable forwarding for port %d", newPort));
+            return false;
         }
+        return true;
     }
 
     // right, keep streams open - forever!

src/main/java/mpo/dayon/assistant/network/NetworkAssistantEngineConfiguration.java

@@ -5,8 +5,6 @@
 
 import java.util.Objects;
 
-import static mpo.dayon.common.utils.SystemUtilities.DEFAULT_TOKEN_SERVER_URL;
-
 public class NetworkAssistantEngineConfiguration extends Configuration {
 	private static final String PREF_VERSION = "assistant.network.version";
 

src/main/java/mpo/dayon/assisted/gui/Assisted.java

@@ -37,6 +37,7 @@
 import static java.lang.String.format;
 import static java.lang.String.valueOf;
 import static mpo.dayon.common.babylon.Babylon.translate;
+import static mpo.dayon.common.configuration.Configuration.DEFAULT_TOKEN_SERVER_URL;
 import static mpo.dayon.common.gui.common.ImageUtilities.getOrCreateIcon;
 import static mpo.dayon.common.utils.SystemUtilities.*;
 
@@ -62,6 +63,8 @@ public class Assisted implements Subscriber, ClipboardOwner {
 
     private final AtomicBoolean shareAllScreens = new AtomicBoolean(false);
 
+    private String token;
+
     public Assisted(String tokenServerUrl) {
         networkConfiguration = new NetworkAssistedEngineConfiguration();
 
@@ -144,7 +147,7 @@ private boolean configureConnection(String serverName, String portNumber, boolea
 
     private boolean requestConnectionSettings() {
         networkConfiguration = new NetworkAssistedEngineConfiguration();
-        ConnectionSettingsDialog connectionSettingsDialog = new ConnectionSettingsDialog(networkConfiguration);
+        ConnectionSettingsDialog connectionSettingsDialog = new ConnectionSettingsDialog(networkConfiguration, token);
 
         final boolean ok = DialogFactory.showOkCancel(frame, translate("connection.settings"), connectionSettingsDialog.getTabbedPane(), false, () -> {
             final String token = connectionSettingsDialog.getToken().trim();
@@ -186,8 +189,9 @@ private static String validatePortNumber(String portNumber) {
     private void applyConnectionSettings(ConnectionSettingsDialog connectionSettingsDialog) {
         CompletableFuture.supplyAsync(() -> {
             final NetworkAssistedEngineConfiguration newConfiguration;
-            String token = connectionSettingsDialog.getToken().trim();
-            if (!token.isEmpty()) {
+            String tokenString = connectionSettingsDialog.getToken().trim();
+            if (!tokenString.isEmpty()) {
+                this.token = tokenString;
                 final Cursor cursor = frame.getCursor();
                 frame.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
                 String connectionParams = null;
@@ -212,6 +216,7 @@ private void applyConnectionSettings(ConnectionSettingsDialog connectionSettings
                 networkConfiguration = newConfiguration;
                 networkConfiguration.persist();
                 networkEngine.configure(networkConfiguration);
+                frame.onConnecting(networkConfiguration.getServerName(), networkConfiguration.getServerPort());
             }
             Log.info("NetworkConfiguration " + networkConfiguration);
         });
@@ -265,7 +270,6 @@ private class NetWorker extends SwingWorker<String, String> {
         @Override
         protected String doInBackground() {
             if (isConfigured() && !isCancelled()) {
-                frame.onConnecting(networkConfiguration.getServerName(), networkConfiguration.getServerPort());
                 networkEngine.configure(networkConfiguration);
                 networkEngine.connect();
             }

src/main/java/mpo/dayon/assisted/gui/ConnectionSettingsDialog.java

@@ -25,7 +25,7 @@ class ConnectionSettingsDialog {
 
     private final JTextField assistantTokenTextField;
 
-    ConnectionSettingsDialog(NetworkAssistedEngineConfiguration configuration) {
+    ConnectionSettingsDialog(NetworkAssistedEngineConfiguration configuration, String token) {
 
         JPanel connectionSettingsDialog = new JPanel(new GridLayout(2, 2, 10, 10));
         connectionSettingsDialog.setBorder(BorderFactory.createEmptyBorder(15, 0, 0, 0));
@@ -46,7 +46,7 @@ class ConnectionSettingsDialog {
         connectionTokenDialog.setBorder(BorderFactory.createEmptyBorder(15, 0, 0, 0));
 
         final JLabel assistantToken = new JLabel(getOrCreateIcon(ImageNames.KEY));
-        assistantTokenTextField = new JTextField("", 7);
+        assistantTokenTextField = new JTextField(token, 7);
         assistantTokenTextField.setMargin(new Insets(2,2,2,2));
         assistantTokenTextField.setFont(new Font("Sans Serif", Font.PLAIN, 26));
         assistantTokenTextField.addMouseListener(clearTextOnDoubleClick(assistantTokenTextField));

src/main/java/mpo/dayon/assisted/network/NetworkAssistedEngineConfiguration.java

@@ -5,8 +5,6 @@
 
 import java.util.Objects;
 
-import static mpo.dayon.common.utils.SystemUtilities.DEFAULT_TOKEN_SERVER_URL;
-
 public class NetworkAssistedEngineConfiguration extends Configuration {
     private static final String PREF_VERSION = "assisted.network.version";
 

src/main/java/mpo/dayon/common/configuration/Configuration.java

@@ -1,6 +1,12 @@
 package mpo.dayon.common.configuration;
 
 public abstract class Configuration {
+	public static final String DEFAULT_TOKEN_SERVER_URL = "https://fensterkitt.ch/dayon/";
+
+	public final String getDefaultTokenServerUrl() {
+		return DEFAULT_TOKEN_SERVER_URL;
+	}
+
 	public final void persist() {
 		persist(false);
 	}

src/main/java/mpo/dayon/common/gui/common/BaseFrame.java

@@ -30,6 +30,7 @@
 import static java.awt.GridBagConstraints.HORIZONTAL;
 import static java.lang.String.format;
 import static mpo.dayon.common.babylon.Babylon.translate;
+import static mpo.dayon.common.configuration.Configuration.DEFAULT_TOKEN_SERVER_URL;
 import static mpo.dayon.common.gui.common.ImageNames.FINGERPRINT;
 import static mpo.dayon.common.gui.common.ImageUtilities.getOrCreateIcon;
 import static mpo.dayon.common.gui.toolbar.ToolBar.*;

src/main/java/mpo/dayon/common/utils/SystemUtilities.java

@@ -28,7 +28,6 @@ public final class SystemUtilities {
     public static final String JAVA_CLASS_PATH = "java.class.path";
     public static final String FLATPAK_BROWSER = "/app/bin/dayon.browser";
     private static final String JAVA_VENDOR = "java.vendor";
-    public static final String DEFAULT_TOKEN_SERVER_URL = "https://fensterkitt.ch/dayon/";
     private static final Pattern FQ_HOSTNAME_REGEX = Pattern.compile("^([a-zA-Z\\d][a-zA-Z\\d\\-]{0,61}[a-zA-Z\\d]\\.)*[a-zA-Z]{2,}$");
     private static final Pattern IPV4_REGEX = Pattern.compile("(\\d{1,3})");
 

src/main/resources/Babylon.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = You should use the same input language on both computers.
 comm.error       = Communication error
 comm.error.msg1  = The program has encountered a communication error [%s].
 
+port.error       = Warning
+port.error.msg1  = Port %s is not reachable from the internet.\nPeers from outside your network will not be able to connect.
+
 # Connection ...
 
 connected         = Connected - happy session!

src/main/resources/Babylon_de.properties

@@ -51,6 +51,9 @@ keyboard.error.msg3 = Sie sollten auf beiden Rechnern dieselbe Eingabesprache nu
 comm.error       = Kommunikationsfehler
 comm.error.msg1  = Es ist ein Kommunikationsfelher aufgetreten [%s].
 
+port.error       = Warnung
+port.error.msg1  = Der Port %s ist vom Internet her nicht erreichbar.\nComputer ausserhalb ihres Netzwerks werden sich nicht verbinden k\u00F6nnen.
+
 # Connection ...
 
 connected         = Verbunden - Happy Session!

src/main/resources/Babylon_es.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = Deber\u00EDas usar el mismo idioma de entrada en las dos c
 comm.error       = Error de comunicaci\u00F3n
 comm.error.msg1  = El programa ha tenido un error de comunicaci\u00F3n [%s].
 
+port.error       = Aviso de advertencia
+port.error.msg1  = El puerto %s no es accesible desde Internet.\nLos pares de fuera de su red no podr\u00E1n conectarse.
+
 # Connection ...
 
 connected         = Conectado - \u00A1Feliz sesi\u00F3n!

src/main/resources/Babylon_fr.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = Vous devez utiliser la m\u00EAme langue de clavier sur les
 comm.error       = Erreur de Communication
 comm.error.msg1  = Une erreur de communication est survenue dans l'application [%s].
 
+port.error       = Attention
+port.error.msg1  = Le port X n'est pas accessible depuis l'internet.\nLes homologues ext\u00E9rieurs \u00E0 votre r\u00E9seau ne pourront pas se connecter.
+
 # Connection ...
 
 connected         = Connect\u00E9 - bonne session!

src/main/resources/Babylon_it.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = Dovresti usare la stessa lingua di input su entrambi i com
 comm.error       = Errore di comunicazione
 comm.error.msg1  = Il programma ha riscontrato un errore di comunicazione [%s].
 
+port.error       = Attenzione
+port.error.msg1  = La porta %s non \u00E8 raggiungibile da Internet.\nI peer esterni alla rete non potranno connettersi.
+
 # Connection ...
 
 connected         = Connesso - buona sessione!

src/main/resources/Babylon_ru.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = \u0412\u044B \u0434\u043E\u043B\u0436\u043D\u044B \u0438\u
 comm.error       = \u041E\u0448\u0438\u0431\u043A\u0430 \u0441\u0432\u044F\u0437\u0438
 comm.error.msg1  = \u041F\u0440\u043E\u0433\u0440\u0430\u043C\u043C\u0430 \u043E\u0431\u043D\u0430\u0440\u0443\u0436\u0438\u043B\u0430 \u043E\u0448\u0438\u0431\u043A\u0443 \u0441\u0432\u044F\u0437\u0438 [%s].
 
+port.error       = \u041F\u0440\u0435\u0434\u0443\u043F\u0440\u0435\u0436\u0434\u0435\u043D\u0438\u0435
+port.error.msg1  = \u041F\u043E\u0440\u0442 %s \u043D\u0435\u0434\u043E\u0441\u0442\u0443\u043F\u0435\u043D \u0438\u0437 \u0418\u043D\u0442\u0435\u0440\u043D\u0435\u0442\u0430.\n\u041F\u0438\u0440\u0438\u043D\u0433\u0438, \u043D\u0430\u0445\u043E\u0434\u044F\u0449\u0438\u0435\u0441\u044F \u0437\u0430 \u043F\u0440\u0435\u0434\u0435\u043B\u0430\u043C\u0438 \u0432\u0430\u0448\u0435\u0439 \u0441\u0435\u0442\u0438, \u043D\u0435 \u0441\u043C\u043E\u0433\u0443\u0442 \u043F\u043E\u0434\u043A\u043B\u044E\u0447\u0438\u0442\u044C\u0441\u044F.
+
 # Connection ...
 
 connected         = \u041F\u043E\u0434\u043A\u043B\u044E\u0447\u0438\u043B\u0441\u044F - \u0443\u0434\u0430\u0447\u043D\u043E\u0439 \u0441\u0435\u0441\u0441\u0438\u0438!

src/main/resources/Babylon_sv.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = Undvik olika tangentbordsspr\u00E5k p\u00E5 datorerna.
 comm.error       = Kommunikationsfel
 comm.error.msg1  = Programmet har st\u00F6tt p\u00E5 ett kommunikationsfel [%s].
 
+port.error       = Varning
+port.error.msg1  = Port %s \u00E4r inte n\u00E5bar fr\u00E5n internet. Motparter utanf\u00F6r ditt n\u00E4tverk kommer inte att kunna ansluta.
+
 # Connection ...
 
 connected         = Ansluten - Lycka till!

src/main/resources/Babylon_tr.properties

@@ -55,6 +55,9 @@ keyboard.error.msg3 = \u0130ki bilgisayarda da ayn\u0131 giri\u015F dilini kulla
 comm.error       = Ileti\u015Fim hatas\u0131
 comm.error.msg1  = Program ileti\u015Fim hatas\u0131yla kar\u015F\u0131la\u015Ft\u0131 [%s].
 
+port.error       = Uyar\u0131
+port.error.msg1  = Port %s internetten eri\u015Filebilir de\u011Fil.\nA\u011F\u0131n\u0131z\u0131n d\u0131\u015F\u0131ndan gelen e\u015Fler ba\u011Flanamayacakt\u0131r.
+
 # Connection ...
 
 connected         = Ba\u011Fland\u0131 - mutlu ba\u011Flant\u0131lar!

src/main/resources/Babylon_zh.properties

@@ -80,6 +80,11 @@ comm.error       = \u4F1A\u8BDD\u4E2D\u65AD
 # The program has encountered a communication error [%s].
 comm.error.msg1  = \u8FDE\u63A5\u88AB\u4E2D\u65AD\u4E86 [%s]
 
+# Warning
+port.error       = \u8B66\u544A
+# Port %s is not reachable from the internet.\nPeers from outside your network will not be able to connect.
+port.error.msg1  = \u7AEF\u53E3 %s \u65E0\u6CD5\u4ECE\u4E92\u8054\u7F51\u8BBF\u95EE\u3002\u7F51\u7EDC\u5916\u90E8\u7684\u5BF9\u7B49\u65B9\u5C06\u65E0\u6CD5\u8FDE\u63A5\u3002
+
 # Connection ...
 
 # Connected - happy session!

src/test/java/mpo/dayon/assistant/network/NetworkAssistantEngineTest.java

@@ -3,6 +3,8 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.*;
 
 class NetworkAssistantEngineTest {
@@ -41,4 +43,34 @@ void testCancel() {
         // then
         verify(listener).onDisconnecting();
     }
+
+    @Test
+    void selfTestShouldFailIfPublicIpIsNull() {
+        // given
+        String publicIp = null;
+        engine.configure(new NetworkAssistantEngineConfiguration(12345, ""));
+
+        // when // then
+        assertFalse(engine.selfTest(publicIp));
+    }
+
+    @Test
+    void selfTestShouldFailForUnreachablePort() {
+        // given
+        String publicIp = "1.2.3.4";
+        engine.configure(new NetworkAssistantEngineConfiguration(5, ""));
+
+        // when // then
+        assertFalse(engine.selfTest(publicIp));
+    }
+
+    @Test
+    void selfTestShouldSucceedForReachablePort() {
+        // given
+        String publicIp = "127.0.0.1";
+        engine.configure(new NetworkAssistantEngineConfiguration(12345, ""));
+
+        // when // then
+        assertTrue(engine.selfTest(publicIp));
+    }
 }