CLI UI: do not print stacktrace if 'open' command is not available

langstream-cli/src/main/java/ai/langstream/cli/commands/applications/UIAppCmd.java

@@ -44,11 +44,13 @@
 import lombok.AllArgsConstructor;
 import lombok.Data;
 import lombok.SneakyThrows;
+import lombok.extern.slf4j.Slf4j;
 import org.xnio.OptionMap;
 import org.xnio.Xnio;
 import picocli.CommandLine;
 
 @CommandLine.Command(name = "ui", header = "Run UI for interact with the application")
+@Slf4j
 public class UIAppCmd extends BaseApplicationCmd {
 
     @CommandLine.Parameters(description = "Application ID")
@@ -165,10 +167,20 @@ public static Undertow startServer(
         server.start();
         port.set(((InetSocketAddress) server.getListenerInfo().get(0).getAddress()).getPort());
 
-        new ProcessBuilder("open", "http://localhost:" + port).start().waitFor();
+        openBrowserAtPort("open", port.get());
+
         return server;
     }
 
+    static void openBrowserAtPort(String openCommand, int port) {
+        try {
+            new ProcessBuilder(openCommand, "http://localhost:" + port).start().waitFor();
+        } catch (InterruptedException interruptedException) {
+            Thread.currentThread().interrupt();
+        } catch (IOException ioException) {
+        }
+    }
+
     @Data
     public static class AppModel {
         private String baseUrl;

langstream-cli/src/test/java/ai/langstream/cli/commands/applications/UIAppCmdTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright DataStax, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package ai.langstream.cli.commands.applications;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class UIAppCmdTest {
+
+    @Test
+    void openBrowser() {
+        // ok
+        UIAppCmd.openBrowserAtPort("echo", 9029);
+        // fail
+        UIAppCmd.openBrowserAtPort("fail", 9029);
+    }
+}