Recognize null value in json payload using the reflection free serializer

Author: mariofusco

extensions/resteasy-reactive/rest-jackson/deployment/src/main/java/io/quarkus/resteasy/reactive/jackson/deployment/processor/JacksonDeserializerFactory.java

@@ -475,10 +475,16 @@ private static ResultHandle readValueForPrimitiveFields(BytecodeCreator bytecode
         AssignableResultHandle result = bytecode.createVariable(DescriptorUtils.typeToString(fieldType));
 
         BranchResult isValueNull = bytecode.ifNull(valueNode);
+
         BytecodeCreator isValueNullTrue = isValueNull.trueBranch();
         isValueNullTrue.assign(result, JacksonSerializationUtils.getDefaultValue(isValueNullTrue, fieldType));
 
-        BytecodeCreator isValueNullFalse = isValueNull.falseBranch();
+        BranchResult isNullNode = isValueNull.falseBranch()
+                .ifTrue(isValueNull.falseBranch().invokeVirtualMethod(ofMethod(JsonNode.class, "isNull", boolean.class),
+                        valueNode));
+        isNullNode.trueBranch().assign(result, JacksonSerializationUtils.getDefaultValue(isNullNode.trueBranch(), fieldType));
+
+        BytecodeCreator isValueNullFalse = isNullNode.falseBranch();
 
         ResultHandle convertedValue = switch (fieldType.name().toString()) {
             case "java.lang.String" -> isValueNullFalse.invokeVirtualMethod(ofMethod(JsonNode.class, "asText", String.class),

extensions/resteasy-reactive/rest-jackson/deployment/src/test/java/io/quarkus/resteasy/reactive/jackson/deployment/test/AbstractSimpleJsonTest.java

@@ -772,6 +772,18 @@ public void testNullMapEcho() {
                 .body("properties", Matchers.nullValue());
     }
 
+    @Test
+    public void testNullStringEcho() {
+        RestAssured
+                .with()
+                .body("{\"text\": null}")
+                .contentType("application/json; charset=utf-8")
+                .post("/simple/null-string-echo")
+                .then()
+                .statusCode(400)
+                .body(containsString("must not be null"));
+    }
+
     @Test
     public void testItem() {
         RestAssured

extensions/resteasy-reactive/rest-jackson/deployment/src/test/java/io/quarkus/resteasy/reactive/jackson/deployment/test/SimpleJsonResource.java

@@ -152,6 +152,12 @@ public MapWrapper echoNullMap(MapWrapper mapWrapper) {
         return mapWrapper;
     }
 
+    @POST
+    @Path("/null-string-echo")
+    public String echoNullString(@Valid StringWrapper input) {
+        return input.text();
+    }
+
     @GET
     @Path("/abstract-cat")
     public AbstractPet getAbstractCat() {

extensions/resteasy-reactive/rest-jackson/deployment/src/test/java/io/quarkus/resteasy/reactive/jackson/deployment/test/SimpleJsonTest.java

@@ -29,7 +29,7 @@ public JavaArchive get() {
                                     Fruit.class, Price.class, DogRecord.class, ItemExtended.class, Book.class, LombokBook.class,
                                     PrimitiveTypesBean.class, PrimitiveTypesRecord.class, TokenResponse.class,
                                     ItemJsonValuePublicMethod.class, ItemJsonValuePublicField.class,
-                                    ItemJsonValuePrivateMethod.class, ItemJsonValuePrivateField.class)
+                                    ItemJsonValuePrivateMethod.class, ItemJsonValuePrivateField.class, StringWrapper.class)
                             .addAsResource(new StringAsset("admin-expression=admin\n" +
                                     "user-expression=user\n" +
                                     "birth-date-roles=alice,bob\n"), "application.properties");

extensions/resteasy-reactive/rest-jackson/deployment/src/test/java/io/quarkus/resteasy/reactive/jackson/deployment/test/SimpleJsonWithReflectionFreeSerializersTest.java

@@ -31,7 +31,7 @@ public JavaArchive get() {
                                     Fruit.class, Price.class, DogRecord.class, ItemExtended.class, Book.class, LombokBook.class,
                                     PrimitiveTypesBean.class, PrimitiveTypesRecord.class, TokenResponse.class,
                                     ItemJsonValuePublicMethod.class, ItemJsonValuePublicField.class,
-                                    ItemJsonValuePrivateMethod.class, ItemJsonValuePrivateField.class)
+                                    ItemJsonValuePrivateMethod.class, ItemJsonValuePrivateField.class, StringWrapper.class)
                             .addAsResource(new StringAsset("admin-expression=admin\n" +
                                     "user-expression=user\n" +
                                     "birth-date-roles=alice,bob\n" +

extensions/resteasy-reactive/rest-jackson/deployment/src/test/java/io/quarkus/resteasy/reactive/jackson/deployment/test/StringWrapper.java

@@ -0,0 +1,6 @@
+package io.quarkus.resteasy.reactive.jackson.deployment.test;
+
+import jakarta.validation.constraints.NotNull;
+
+public record StringWrapper(@NotNull String text) {
+}