Properly take produced media type into account when building validation error report

extensions/hibernate-validator/runtime/pom.xml

@@ -82,6 +82,11 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <groupId>io.quarkus.resteasy.reactive</groupId>
+            <artifactId>resteasy-reactive</artifactId>
+            <optional>true</optional>
+        </dependency>
         <dependency>
             <groupId>org.jboss.spec.javax.ws.rs</groupId>
             <artifactId>jboss-jaxrs-api_2.1_spec</artifactId>

extensions/hibernate-validator/runtime/src/main/java/io/quarkus/hibernate/validator/runtime/jaxrs/ResteasyReactiveViolationExceptionMapper.java

@@ -1,6 +1,9 @@
 package io.quarkus.hibernate.validator.runtime.jaxrs;
 
+import static io.quarkus.hibernate.validator.runtime.jaxrs.ValidatorMediaTypeUtil.SUPPORTED_MEDIA_TYPES;
+
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
@@ -10,21 +13,18 @@
 import javax.validation.ElementKind;
 import javax.validation.Path;
 import javax.validation.ValidationException;
-import javax.ws.rs.core.Context;
-import javax.ws.rs.core.HttpHeaders;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
 import javax.ws.rs.core.Response.Status;
 import javax.ws.rs.ext.ExceptionMapper;
 import javax.ws.rs.ext.Provider;
 
-import org.jboss.resteasy.api.validation.Validation;
+import org.jboss.resteasy.reactive.server.core.CurrentRequestManager;
 
 @Provider
 public class ResteasyReactiveViolationExceptionMapper implements ExceptionMapper<ValidationException> {
 
-    @Context
-    HttpHeaders headers;
+    private static final String VALIDATION_HEADER = "validation-exception";
 
     @Override
     public Response toResponse(ValidationException exception) {
@@ -69,10 +69,14 @@ private boolean isReturnValueViolation(ConstraintViolation<?> violation) {
     private Response buildViolationReportResponse(ConstraintViolationException cve) {
         Status status = Status.BAD_REQUEST;
         Response.ResponseBuilder builder = Response.status(status);
-        builder.header(Validation.VALIDATION_HEADER, "true");
+        builder.header(VALIDATION_HEADER, "true");
 
+        var rrContext = CurrentRequestManager.get();
         // Check standard media types.
-        MediaType mediaType = ValidatorMediaTypeUtil.getAcceptMediaTypeFromSupported(headers.getAcceptableMediaTypes());
+        MediaType mediaType = ValidatorMediaTypeUtil.getAcceptMediaType(
+                rrContext.getHttpHeaders().getAcceptableMediaTypes(),
+                rrContext.getTarget() != null ? Arrays.asList(rrContext.getTarget().getProduces().getSortedMediaTypes())
+                        : SUPPORTED_MEDIA_TYPES);
         if (mediaType == null) {
             mediaType = MediaType.APPLICATION_JSON_TYPE;
         }

extensions/hibernate-validator/runtime/src/main/java/io/quarkus/hibernate/validator/runtime/jaxrs/ValidatorMediaTypeUtil.java

@@ -10,7 +10,7 @@
  */
 public final class ValidatorMediaTypeUtil {
 
-    private static final List<MediaType> SUPPORTED_MEDIA_TYPES = Arrays.asList(
+    static final List<MediaType> SUPPORTED_MEDIA_TYPES = Arrays.asList(
             MediaType.APPLICATION_JSON_TYPE,
             MediaType.APPLICATION_XML_TYPE,
             MediaType.TEXT_XML_TYPE,
@@ -20,16 +20,6 @@ private ValidatorMediaTypeUtil() {
 
     }
 
-    /**
-     * Look up the right media type taking into account the HTTP request and the supported media types.
-     *
-     * @param mediaTypesFromRequest list of media types in the HTTP request.
-     * @return one supported media type from either the HTTP request or the annotation.
-     */
-    public static MediaType getAcceptMediaTypeFromSupported(List<MediaType> mediaTypesFromRequest) {
-        return getAcceptMediaType(mediaTypesFromRequest, SUPPORTED_MEDIA_TYPES);
-    }
-
     /**
      * Look up the right media type taking into account the HTTP request and the media types defined in the `@Produces`
      * annotation.

integration-tests/hibernate-validator-resteasy-reactive/src/main/java/io/quarkus/it/hibernate/validator/TextResource.java

@@ -0,0 +1,27 @@
+package io.quarkus.it.hibernate.validator;
+
+import javax.validation.constraints.Digits;
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+
+@Path("text")
+public class TextResource {
+
+    @GET
+    @Path("/validate/{id}")
+    public String validate(
+            @Digits(integer = 5, fraction = 0, message = "numeric value out of bounds") @PathParam("id") String id) {
+        return id;
+    }
+
+    @GET
+    @Path("/validate/text/{id}")
+    @Produces(MediaType.TEXT_PLAIN)
+    public String validateText(
+            @Digits(integer = 5, fraction = 0, message = "numeric value out of bounds") @PathParam("id") String id) {
+        return id;
+    }
+}

integration-tests/hibernate-validator-resteasy-reactive/src/test/java/io/quarkus/it/hibernate/validator/TextResourceTest.java

@@ -0,0 +1,28 @@
+package io.quarkus.it.hibernate.validator;
+
+import static io.restassured.RestAssured.when;
+
+import org.junit.jupiter.api.Test;
+
+import io.quarkus.test.junit.QuarkusTest;
+import io.restassured.http.ContentType;
+
+@QuarkusTest
+public class TextResourceTest {
+
+    @Test
+    public void fetchDefault() {
+        when().get("/text/validate/boom")
+                .then()
+                .statusCode(400)
+                .contentType(ContentType.TEXT);
+    }
+
+    @Test
+    public void fetchText() {
+        when().get("/text/validate/boom")
+                .then()
+                .statusCode(400)
+                .contentType(ContentType.TEXT);
+    }
+}