WebSockets Next: enable configuration of supported subprotocols

- add WebSocketConnection#subprotocol() that can be used to obtain the
subprotocol selected by the handshake
- the values defined with quarkus.websockets-next.supported-subprotocols
contribute to the set of subprotocols passed to the HTTP server
configuration
- also add constants for handshake headers defined by the RFC
- resolves #39465

extensions/websockets-next/server/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessor.java

@@ -68,6 +68,7 @@
 import io.quarkus.websockets.next.runtime.JsonTextMessageCodec;
 import io.quarkus.websockets.next.runtime.WebSocketEndpoint.ExecutionModel;
 import io.quarkus.websockets.next.runtime.WebSocketEndpointBase;
+import io.quarkus.websockets.next.runtime.WebSocketHttpServerOptionsCustomizer;
 import io.quarkus.websockets.next.runtime.WebSocketServerRecorder;
 import io.quarkus.websockets.next.runtime.WebSocketSessionContext;
 import io.smallrye.mutiny.Multi;
@@ -200,7 +201,9 @@ public void registerRoutes(WebSocketServerRecorder recorder, HttpRootPathBuildIt
     @BuildStep
     AdditionalBeanBuildItem additionalBeans() {
         return AdditionalBeanBuildItem.builder().setUnremovable()
-                .addBeanClasses(Codecs.class, JsonTextMessageCodec.class, ConnectionManager.class).build();
+                .addBeanClasses(Codecs.class, JsonTextMessageCodec.class, ConnectionManager.class,
+                        WebSocketHttpServerOptionsCustomizer.class)
+                .build();
     }
 
     @BuildStep

extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/test/subprotocol/SubprotocolNotAvailableTest.java

@@ -0,0 +1,60 @@
+package io.quarkus.websockets.next.test.subprotocol;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.net.URI;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import jakarta.inject.Inject;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.netty.handler.codec.http.websocketx.WebSocketClientHandshakeException;
+import io.quarkus.test.QuarkusUnitTest;
+import io.quarkus.test.common.http.TestHTTPResource;
+import io.quarkus.websockets.next.OnOpen;
+import io.quarkus.websockets.next.WebSocket;
+import io.quarkus.websockets.next.test.utils.WSClient;
+import io.vertx.core.Vertx;
+import io.vertx.core.http.WebSocketConnectOptions;
+
+public class SubprotocolNotAvailableTest {
+
+    @RegisterExtension
+    public static final QuarkusUnitTest test = new QuarkusUnitTest()
+            .withApplicationRoot(root -> {
+                root.addClasses(Endpoint.class, WSClient.class);
+            });
+
+    @Inject
+    Vertx vertx;
+
+    @TestHTTPResource("endpoint")
+    URI endUri;
+
+    @Test
+    void testConnectionRejected() {
+        CompletionException e = assertThrows(CompletionException.class,
+                () -> new WSClient(vertx).connect(new WebSocketConnectOptions().addSubProtocol("oak"), endUri));
+        Throwable cause = e.getCause();
+        assertTrue(cause instanceof WebSocketClientHandshakeException);
+        assertFalse(Endpoint.OPEN_CALLED.get());
+    }
+
+    @WebSocket(path = "/endpoint")
+    public static class Endpoint {
+
+        static final AtomicBoolean OPEN_CALLED = new AtomicBoolean();
+
+        @OnOpen
+        void open() {
+            OPEN_CALLED.set(true);
+        }
+
+    }
+
+}

extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/test/subprotocol/SubprotocolSelectedTest.java

@@ -0,0 +1,63 @@
+package io.quarkus.websockets.next.test.subprotocol;
+
+import static io.quarkus.websockets.next.WebSocketConnection.HandshakeRequest.SEC_WEBSOCKET_PROTOCOL;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.net.URI;
+import java.util.concurrent.ExecutionException;
+
+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.OnOpen;
+import io.quarkus.websockets.next.WebSocket;
+import io.quarkus.websockets.next.WebSocketConnection;
+import io.quarkus.websockets.next.test.utils.WSClient;
+import io.smallrye.mutiny.Uni;
+import io.vertx.core.Vertx;
+import io.vertx.core.http.WebSocketConnectOptions;
+
+public class SubprotocolSelectedTest {
+
+    @RegisterExtension
+    public static final QuarkusUnitTest test = new QuarkusUnitTest()
+            .withApplicationRoot(root -> {
+                root.addClasses(Endpoint.class, WSClient.class);
+            }).overrideConfigKey("quarkus.websockets-next.supported-subprotocols", "oak,larch");
+
+    @Inject
+    Vertx vertx;
+
+    @TestHTTPResource("endpoint")
+    URI endUri;
+
+    @Test
+    void testSubprotocol() throws InterruptedException, ExecutionException {
+        WSClient client = new WSClient(vertx).connect(new WebSocketConnectOptions().addSubProtocol("oak"), endUri);
+        assertEquals("ok", client.waitForNextMessage().toString());
+    }
+
+    @WebSocket(path = "/endpoint")
+    public static class Endpoint {
+
+        @Inject
+        WebSocketConnection connection;
+
+        @OnOpen
+        Uni<Void> open() {
+            if (connection.handshakeRequest().header(SEC_WEBSOCKET_PROTOCOL) == null) {
+                return connection.sendText("Sec-WebSocket-Protocol not set: " + connection.handshakeRequest().headers());
+            } else if ("oak".equals(connection.subprotocol())) {
+                return connection.sendText("ok");
+            } else {
+                return connection.sendText("Invalid protocol: " + connection.subprotocol());
+            }
+        }
+
+    }
+
+}

extensions/websockets-next/server/runtime/src/main/java/io/quarkus/websockets/next/WebSocketConnection.java

@@ -91,6 +91,12 @@ default void closeAndAwait() {
      */
     HandshakeRequest handshakeRequest();
 
+    /**
+     *
+     * @return the subprotocol selected by the handshake
+     */
+    String subprotocol();
+
     /**
      *
      * @return the time when this connection was created
@@ -172,6 +178,31 @@ interface HandshakeRequest {
          */
         String query();
 
+        /**
+         * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-57">The WebSocket Protocol</a>.
+         */
+        public static final String SEC_WEBSOCKET_KEY = "Sec-WebSocket-Key";
+
+        /**
+         * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-58">The WebSocket Protocol</a>.
+         */
+        public static final String SEC_WEBSOCKET_EXTENSIONS = "Sec-WebSocket-Extensions";
+
+        /**
+         * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-58">The WebSocket Protocol</a>.
+         */
+        public static final String SEC_WEBSOCKET_ACCEPT = "Sec-WebSocket-Accept";
+
+        /**
+         * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-59">The WebSocket Protocol</a>.
+         */
+        public static final String SEC_WEBSOCKET_PROTOCOL = "Sec-WebSocket-Protocol";
+
+        /**
+         * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-60">The WebSocket Protocol</a>.
+         */
+        public static final String SEC_WEBSOCKET_VERSION = "Sec-WebSocket-Version";
+
     }
 
 }

extensions/websockets-next/server/runtime/src/main/java/io/quarkus/websockets/next/WebSocketsRuntimeConfig.java

@@ -1,6 +1,7 @@
 package io.quarkus.websockets.next;
 
 import java.time.Duration;
+import java.util.List;
 import java.util.Optional;
 
 import io.quarkus.runtime.annotations.ConfigPhase;
@@ -11,6 +12,13 @@
 @ConfigRoot(phase = ConfigPhase.RUN_TIME)
 public interface WebSocketsRuntimeConfig {
 
+    /**
+     * See <a href="https://datatracker.ietf.org/doc/html/rfc6455#page-12">The WebSocket Protocol</a>
+     *
+     * @return the supported subprotocols
+     */
+    Optional<List<String>> supportedSubprotocols();
+
     /**
      * TODO Not implemented yet.
      *

extensions/websockets-next/server/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketConnectionImpl.java

@@ -119,6 +119,11 @@ public HandshakeRequest handshakeRequest() {
         return handshakeRequest;
     }
 
+    @Override
+    public String subprotocol() {
+        return webSocket.subProtocol();
+    }
+
     @Override
     public Instant creationTime() {
         return creationTime;

extensions/websockets-next/server/runtime/src/main/java/io/quarkus/websockets/next/runtime/WebSocketHttpServerOptionsCustomizer.java

@@ -0,0 +1,28 @@
+package io.quarkus.websockets.next.runtime;
+
+import java.util.List;
+
+import jakarta.enterprise.context.Dependent;
+import jakarta.inject.Inject;
+
+import io.quarkus.vertx.http.HttpServerOptionsCustomizer;
+import io.quarkus.websockets.next.WebSocketsRuntimeConfig;
+import io.vertx.core.http.HttpServerOptions;
+
+@Dependent
+public class WebSocketHttpServerOptionsCustomizer implements HttpServerOptionsCustomizer {
+
+    @Inject
+    WebSocketsRuntimeConfig config;
+
+    @Override
+    public void customizeHttpServer(HttpServerOptions options) {
+        config.supportedSubprotocols().orElse(List.of()).forEach(options::addWebSocketSubProtocol);
+    }
+
+    @Override
+    public void customizeHttpsServer(HttpServerOptions options) {
+        config.supportedSubprotocols().orElse(List.of()).forEach(options::addWebSocketSubProtocol);
+    }
+
+}