Add configuration option for resuming on 404

This is a useful (albeit advanced) option for users
that want to use custom routes to handle
cases where RESTEasy Reactive does not match the
URL path.

Closes: #38840

extensions/resteasy-reactive/quarkus-resteasy-reactive-common/runtime/src/main/java/io/quarkus/resteasy/reactive/common/runtime/ResteasyReactiveConfig.java

@@ -67,4 +67,12 @@ public interface ResteasyReactiveConfig {
      */
     @WithDefault("true")
     boolean failOnDuplicate();
+
+    /**
+     * An advanced option that can be set when they RESTEasy Reactive should NOT reply with 404 when it does not match the URL
+     * path
+     * and instead just pass control onto the next Vert.x handler (if any)
+     */
+    @WithDefault("false")
+    boolean resumeOn404();
 }

extensions/resteasy-reactive/quarkus-resteasy-reactive/deployment/src/main/java/io/quarkus/resteasy/reactive/server/deployment/ResteasyReactiveProcessor.java

@@ -1281,10 +1281,12 @@ public void setupDeployment(BeanContainerBuildItem beanContainerBuildItem,
             servletPresent = true;
         }
 
+        boolean resumeOn404 = servletPresent || !resumeOn404Items.isEmpty() || config.resumeOn404();
+
         RuntimeValue<Deployment> deployment = recorder.createDeployment(deploymentInfo,
                 beanContainerBuildItem.getValue(), shutdownContext, vertxConfig,
                 requestContextFactoryBuildItem.map(RequestContextFactoryBuildItem::getFactory).orElse(null),
-                initClassFactory, launchModeBuildItem.getLaunchMode(), servletPresent || !resumeOn404Items.isEmpty());
+                initClassFactory, launchModeBuildItem.getLaunchMode(), resumeOn404);
 
         quarkusRestDeploymentBuildItemBuildProducer
                 .produce(new ResteasyReactiveDeploymentBuildItem(deployment, deploymentPath));

extensions/resteasy-reactive/quarkus-resteasy-reactive/deployment/src/test/java/io/quarkus/resteasy/reactive/server/test/ResumeOn404ConfigTest.java

@@ -0,0 +1,73 @@
+package io.quarkus.resteasy.reactive.server.test;
+
+import static io.restassured.RestAssured.get;
+
+import java.util.function.Supplier;
+
+import jakarta.enterprise.context.RequestScoped;
+import jakarta.enterprise.event.Observes;
+import jakarta.ws.rs.GET;
+import jakarta.ws.rs.Path;
+import jakarta.ws.rs.Produces;
+import jakarta.ws.rs.core.MediaType;
+
+import org.jboss.shrinkwrap.api.ShrinkWrap;
+import org.jboss.shrinkwrap.api.spec.JavaArchive;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.test.QuarkusUnitTest;
+import io.vertx.ext.web.Router;
+
+public class ResumeOn404ConfigTest {
+
+    @RegisterExtension
+    static QuarkusUnitTest test = new QuarkusUnitTest()
+            .setArchiveProducer(new Supplier<>() {
+                @Override
+                public JavaArchive get() {
+                    return ShrinkWrap.create(JavaArchive.class)
+                            .addClasses(Resource.class, CustomRoute.class);
+                }
+            })
+            .overrideRuntimeConfigKey("quarkus.resteasy-reactive.resume-on-404", "true");
+
+    @Test
+    public void matchingFromResteasyReactive() {
+        get("/test")
+                .then()
+                .statusCode(200);
+    }
+
+    @Test
+    public void matchingFromCustomRoute() {
+        get("/main")
+                .then()
+                .statusCode(200);
+    }
+
+    @Test
+    public void missing() {
+        get("/dummy")
+                .then()
+                .statusCode(404);
+    }
+
+    @Path("/test")
+    @RequestScoped
+    public static class Resource {
+        @GET
+        @Produces(MediaType.TEXT_PLAIN)
+        public String hello() {
+            return "test";
+        }
+
+    }
+
+    public static class CustomRoute {
+
+        public void initMain(@Observes Router router) {
+            router.get("/main").handler(rc -> rc.response().end("main"));
+        }
+    }
+}