Enable returning a Mutiny Buffer from RESTEasy Reactive Resource Method

Resolves: #22694

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

@@ -79,6 +79,7 @@
 import org.jboss.resteasy.reactive.server.processor.scanning.ResponseStatusMethodScanner;
 import org.jboss.resteasy.reactive.server.processor.util.ResteasyReactiveServerDotNames;
 import org.jboss.resteasy.reactive.server.vertx.serializers.ServerMutinyAsyncFileMessageBodyWriter;
+import org.jboss.resteasy.reactive.server.vertx.serializers.ServerMutinyBufferMessageBodyWriter;
 import org.jboss.resteasy.reactive.server.vertx.serializers.ServerVertxAsyncFileMessageBodyWriter;
 import org.jboss.resteasy.reactive.server.vertx.serializers.ServerVertxBufferMessageBodyWriter;
 import org.jboss.resteasy.reactive.spi.BeanFactory;
@@ -216,7 +217,12 @@ MethodScannerBuildItem responseHeaderSupport() {
     @BuildStep
     void vertxIntegration(BuildProducer<MessageBodyWriterBuildItem> writerBuildItemBuildProducer) {
         writerBuildItemBuildProducer.produce(new MessageBodyWriterBuildItem(ServerVertxBufferMessageBodyWriter.class.getName(),
-                Buffer.class.getName(), Collections.singletonList(MediaType.WILDCARD), RuntimeType.SERVER, true,
+                io.vertx.core.buffer.Buffer.class.getName(), Collections.singletonList(MediaType.WILDCARD), RuntimeType.SERVER,
+                true,
+                Priorities.USER));
+        writerBuildItemBuildProducer.produce(new MessageBodyWriterBuildItem(ServerMutinyBufferMessageBodyWriter.class.getName(),
+                io.vertx.mutiny.core.buffer.Buffer.class.getName(), Collections.singletonList(MediaType.WILDCARD),
+                RuntimeType.SERVER, true,
                 Priorities.USER));
         writerBuildItemBuildProducer
                 .produce(new MessageBodyWriterBuildItem(ServerVertxAsyncFileMessageBodyWriter.class.getName(),

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

@@ -232,6 +232,12 @@ public Buffer vertxBuffer() {
         return Buffer.buffer("VERTX-BUFFER");
     }
 
+    @GET
+    @Path("writer/mutiny-buffer")
+    public io.vertx.mutiny.core.buffer.Buffer mutinyBuffer() {
+        return io.vertx.mutiny.core.buffer.Buffer.buffer("MUTINY-BUFFER");
+    }
+
     @GET
     @Path("async/cs/ok")
     public CompletionStage<String> asyncCompletionStageOK() {

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

@@ -183,6 +183,9 @@ public void testWriter() {
 
         RestAssured.get("/simple/writer/vertx-buffer")
                 .then().body(Matchers.equalTo("VERTX-BUFFER"));
+
+        RestAssured.get("/simple/writer/mutiny-buffer")
+                .then().body(Matchers.equalTo("MUTINY-BUFFER"));
     }
 
     @DisabledOnOs(OS.WINDOWS)

independent-projects/resteasy-reactive/server/vertx/src/main/java/org/jboss/resteasy/reactive/server/vertx/serializers/ServerMutinyBufferMessageBodyWriter.java

@@ -0,0 +1,37 @@
+package org.jboss.resteasy.reactive.server.vertx.serializers;
+
+import io.vertx.mutiny.core.buffer.Buffer;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Type;
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.Provider;
+import org.jboss.resteasy.reactive.server.spi.ResteasyReactiveResourceInfo;
+import org.jboss.resteasy.reactive.server.spi.ServerMessageBodyWriter;
+import org.jboss.resteasy.reactive.server.spi.ServerRequestContext;
+
+@Provider
+public class ServerMutinyBufferMessageBodyWriter implements ServerMessageBodyWriter<Buffer> {
+
+    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return true;
+    }
+
+    public void writeTo(Buffer buffer, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType,
+            MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException, WebApplicationException {
+        entityStream.write(buffer.getBytes());
+    }
+
+    @Override
+    public boolean isWriteable(Class<?> type, Type genericType, ResteasyReactiveResourceInfo target, MediaType mediaType) {
+        return true;
+    }
+
+    @Override
+    public void writeResponse(Buffer buffer, Type genericType, ServerRequestContext context) throws WebApplicationException {
+        context.serverResponse().end(buffer.getBytes());
+    }
+}

independent-projects/resteasy-reactive/server/vertx/src/test/java/org/jboss/resteasy/reactive/server/vertx/test/simple/SimpleQuarkusRestResource.java

@@ -229,6 +229,12 @@ public Buffer vertxBuffer() {
         return Buffer.buffer("VERTX-BUFFER");
     }
 
+    @GET
+    @Path("writer/mutiny-buffer")
+    public io.vertx.mutiny.core.buffer.Buffer mutinyBuffer() {
+        return io.vertx.mutiny.core.buffer.Buffer.buffer("MUTINY-BUFFER");
+    }
+
     @GET
     @Path("async/cs/ok")
     public CompletionStage<String> asyncCompletionStageOK() {

independent-projects/resteasy-reactive/server/vertx/src/test/java/org/jboss/resteasy/reactive/server/vertx/test/simple/SimpleQuarkusRestTestCase.java

@@ -182,6 +182,9 @@ public void testWriter() {
 
         RestAssured.get("/simple/writer/vertx-buffer")
                 .then().body(Matchers.equalTo("VERTX-BUFFER"));
+
+        RestAssured.get("/simple/writer/mutiny-buffer")
+                .then().body(Matchers.equalTo("MUTINY-BUFFER"));
     }
 
     @DisabledOnOs(OS.WINDOWS)