Quarkus: Serialization of RestEasy JAXB wrapped collections fails in native mode

[lbroudoux]

Describe the bug

When using the org.jboss.resteasy.annotations.providers.jaxb.Wrapped annotation in JAX-RS resource to force a specific Collection wrapping XML tag, the collection it not serialized in native mode. However it works as expected in JVM mode.

I use the following code:

    @GET
    @Produces({MediaType.APPLICATION_JSON, MediaType.TEXT_XML})
    @Wrapped(element="pastries")
    public List<Pastry> getPastries() {
        return PastryRepository.getPastries();
    }

Expected behavior

When calling my REST endpoint, I expect something like:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<pastries>
   <pastry><name>Tartelette Fraise</name><price>2.0</price><size>S</size><status>available</status></pastry>
   <pastry><name>Eclair Cafe</name><price>2.5</price><size>M</size><status>available</status></pastry>
   <pastry><name>Millefeuille</name><price>4.4</price><size>L</size><status>available</status></pastry>
</pastries>

and that's the result I have when testing in JVM mode.

Actual behavior

When running in native mode, I have the following result:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?><pastries/>

When calling REST endpoint that returns single entity (ex: /pastry/{name}), JAXB serialization works as expected even in native mode.

To Reproduce
Steps to reproduce the behavior:

1. Create a Pastry bean annotated with @RegisterForReflection and @XmlRootElement
2. Create a JAX-RS PastryResource with a method annotated with @Wrapped(element="pastries") and returning a List of Pastry
3. Compile your app in native mode and invoke the JAX-RS endpoint.

I have a demo project here: https://github.com/microcks/api-lifecycle/tree/master/api-pastry-demo/api-implementations/quarkus-api-pastry but it already contains the workaround I found (see below). You will have to remove it first for reproducing the failure.

Configuration

No properties added.

Environment:

• Output of uname -a or ver: Darwin lbroudou1-mac 18.7.0 Darwin Kernel Version 18.7.0: Tue Aug 20 16:57:14 PDT 2019; root:xnu-4903.271.2~2/RELEASE_X86_64 x86_64
• Output of java -version: OpenJDK Runtime Environment AdoptOpenJDK (build 11.0.8+10)
• GraalVM version (if different from Java): used the docker image for native compilation
• Quarkus version or git rev: 1.7.1.Final
• Build tool (ie. output of mvnw --version or gradlew --version): Apache Maven 3.6.3 (cecedd343002696d0abb50b32b541b8a6ba2883f)

Workaround

Found a workaround by adding a reflection-config.json file and the adhoc native compilation flag. Once added the annotation is well managed in native mode and the serialization works as expected.

[
  {
    "name" : "org.jboss.resteasy.plugins.providers.jaxb.JaxbCollection",
    "allDeclaredConstructors" : true,
    "allPublicConstructors" : true,
    "allDeclaredMethods" : true,
    "allPublicMethods" : true,
    "allDeclaredFields" : true,
    "allPublicFields" : true
  },
  {
    "name" : "javax.xml.bind.annotation.W3CDomHandler",
    "allDeclaredConstructors" : true,
    "allPublicConstructors" : true,
    "allDeclaredMethods" : true,
    "allPublicMethods" : true,
    "allDeclaredFields" : true,
    "allPublicFields" : true
  }
]

I think that this setup should be managed within resteasy-jaxb extension as this is a common use-case in RestEasy. If that makes sense for you, I could contribute a PR.

[geoand]

That makes sense to me, PRs very welcome :)

[lbroudoux]

Reading the Writing Extensions guide while building locally the Quarkus modules. Expect PR in few hours / days depending on distractions ;-)

[lbroudoux]

PR #11817 is now submitted