From 6c6a5a41ea6730926d9ff82131559dd75b1fe61d Mon Sep 17 00:00:00 2001
From: Martin Kouba <mkouba@redhat.com>
Date: Wed, 28 Aug 2024 11:32:44 +0200
Subject: [PATCH] WebSockets Next: support endpoints with empty path

- fixes #42808
---
 .../next/deployment/WebSocketProcessor.java   |  3 +
 .../client/ClientEndpointEmptyPathTest.java   | 94 +++++++++++++++++++
 .../next/runtime/WebSocketConnectorBase.java  |  3 +
 3 files changed, 100 insertions(+)
 create mode 100644 extensions/websockets-next/deployment/src/test/java/io/quarkus/websockets/next/test/client/ClientEndpointEmptyPathTest.java

diff --git a/extensions/websockets-next/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketProcessor.java b/extensions/websockets-next/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketProcessor.java
index cf2040a7e2c2a8..39a73e19e1293f 100644
--- a/extensions/websockets-next/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketProcessor.java
+++ b/extensions/websockets-next/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketProcessor.java
@@ -599,6 +599,9 @@ static String mergePath(String prefix, String path) {
     }
 
     static String getPath(String path) {
+        if (path.isEmpty()) {
+            return "";
+        }
         StringBuilder sb = new StringBuilder();
         Matcher m = PATH_PARAM_PATTERN.matcher(path);
         while (m.find()) {
diff --git a/extensions/websockets-next/deployment/src/test/java/io/quarkus/websockets/next/test/client/ClientEndpointEmptyPathTest.java b/extensions/websockets-next/deployment/src/test/java/io/quarkus/websockets/next/test/client/ClientEndpointEmptyPathTest.java
new file mode 100644
index 00000000000000..c166af3e8362bb
--- /dev/null
+++ b/extensions/websockets-next/deployment/src/test/java/io/quarkus/websockets/next/test/client/ClientEndpointEmptyPathTest.java
@@ -0,0 +1,94 @@
+package io.quarkus.websockets.next.test.client;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.net.URI;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import jakarta.inject.Inject;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.test.QuarkusUnitTest;
+import io.quarkus.test.common.http.TestHTTPResource;
+import io.quarkus.websockets.next.OnClose;
+import io.quarkus.websockets.next.OnTextMessage;
+import io.quarkus.websockets.next.WebSocket;
+import io.quarkus.websockets.next.WebSocketClient;
+import io.quarkus.websockets.next.WebSocketClientConnection;
+import io.quarkus.websockets.next.WebSocketConnector;
+
+public class ClientEndpointEmptyPathTest {
+
+    @RegisterExtension
+    public static final QuarkusUnitTest test = new QuarkusUnitTest()
+            .withApplicationRoot(root -> {
+                root.addClasses(ServerEndpoint.class, ClientEndpoint.class);
+            });
+
+    @Inject
+    WebSocketConnector<ClientEndpoint> connector;
+
+    @TestHTTPResource("/")
+    URI uri;
+
+    @Test
+    void testClient() throws InterruptedException {
+        WebSocketClientConnection connection = connector
+                .baseUri(uri)
+                .connectAndAwait();
+        connection.sendTextAndAwait("Hi!");
+
+        assertTrue(ClientEndpoint.MESSAGE_LATCH.await(5, TimeUnit.SECONDS));
+        assertEquals("Hi!", ClientEndpoint.MESSAGES.get(0));
+
+        connection.closeAndAwait();
+        assertTrue(ClientEndpoint.CLOSED_LATCH.await(5, TimeUnit.SECONDS));
+        assertTrue(ServerEndpoint.CLOSED_LATCH.await(5, TimeUnit.SECONDS));
+    }
+
+    @WebSocket(path = "")
+    public static class ServerEndpoint {
+
+        static final CountDownLatch CLOSED_LATCH = new CountDownLatch(1);
+
+        @OnTextMessage
+        String echo(String message) {
+            return message;
+        }
+
+        @OnClose
+        void close() {
+            CLOSED_LATCH.countDown();
+        }
+
+    }
+
+    @WebSocketClient(path = "")
+    public static class ClientEndpoint {
+
+        static final CountDownLatch MESSAGE_LATCH = new CountDownLatch(1);
+
+        static final List<String> MESSAGES = new CopyOnWriteArrayList<>();
+
+        static final CountDownLatch CLOSED_LATCH = new CountDownLatch(1);
+
+        @OnTextMessage
+        void onMessage(String message, WebSocketClientConnection connection) {
+            MESSAGES.add(message);
+            MESSAGE_LATCH.countDown();
+        }
+
+        @OnClose
+        void close() {
+            CLOSED_LATCH.countDown();
+        }
+
+    }
+
+}
diff --git a/extensions/websockets-next/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketConnectorBase.java b/extensions/websockets-next/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketConnectorBase.java
index 1a878b6b6cb184..aa56b3af786da9 100644
--- a/extensions/websockets-next/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketConnectorBase.java
+++ b/extensions/websockets-next/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketConnectorBase.java
@@ -123,6 +123,9 @@ Set<String> getPathParamNames(String path) {
     }
 
     String replacePathParameters(String path) {
+        if (path.isEmpty()) {
+            return "";
+        }
         StringBuilder sb = new StringBuilder();
         Matcher m = PATH_PARAM_PATTERN.matcher(path);
         while (m.find()) {