Model exporter xml - how customize response content-type

[davidef34326447]

Hi community,

i developed a custom XML exporter:

"

/**
 * XML export used to generate XML render on servlets.
 */
@Component(service = ModelExporter.class)
public class CustomXmlExporter implements ModelExporter {
    private static final Logger LOG = LoggerFactory.getLogger(CustomXmlExporter.class);
    @Override
    public boolean isSupported(Class<?> aClass) {
        return true;
    }

    @Override
    public <T> T export(Object model, Class<T> aClass, Map<String, String> options) throws ExportException {
        StringWriter stringWriter = new StringWriter();
        try {
            JAXBContext jaxbContext = JAXBContext.newInstance(model.getClass());
            Marshaller marshaller = jaxbContext.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
            marshaller.marshal(model, stringWriter);
        } catch (JAXBException e) {
            LOG.error("\n Marshell Error : {} ",e);
        }
        return (T) stringWriter.toString();
    }

    @Override
    public String getName() {
        return "custom-exporter";
    }
}

"

and it work fine! 

now, during the integration test, i catched the necessary to customize the response content-type from:application/xml;charset=iso-8859-1 to:application/xml; charset=utf-8.

How can i reach the goal? i don't understand where set the content-type override.

Here my model:

@Exporters({
        @Exporter(name = ExporterConstants.SLING_MODEL_EXPORTER_NAME, selector = "list", extensions = ExporterConstants.SLING_MODEL_EXTENSION, options = {
                @ExporterOption(name = "MapperFeature.SORT_PROPERTIES_ALPHABETICALLY", value = "true"),
                @ExporterOption(name = "SerializationFeature.WRITE_DATES_AS_TIMESTAMPS", value = "false")
        }),
        @Exporter(name = "custom-exporter", extensions = "xml", selector = "list")
})

[Kishore_Kumar_]

Hi @davidef34326447 ,

If you hit your model in browser, whether output is coming fine in XML ?

[davidef34326447]

yes,

1. Content-Type:
   application/xml;charset=iso-8859-1
2. Date:
   Wed, 01 Sep 2021 07:08:34 GMT
3. Transfer-Encoding:
   chunked
4. X-Content-Type-Options:
   nosniff

[Umesh_Thakur]

Can you please have a look on the below article:

http://www.sgaemsolutions.com/2018/01/custom-sling-model-exporter-in-aem-63.html

hope this will help.

Umesh Thakur

[davidef34326447]

copy and past your code (that is the same of mine), i received the same result (no UTF 8):

it's very strange.

[Kishore_Kumar_]

Hi @davidef34326447 ,

you mean encoding format is incorrect ? can u try using it in your custom xml exporter.

marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");

[davidef34326447]

yes.. my issue is related to the response content-type charset wrong. 

also adding the "

marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");

"

i receiving the same result on response content-type.. reading this article "https://howtodoinjava.com/jaxb/marshaller-example/",seems that utf-8 is the default option and it regard the xml first row output "<?xml version="1.0" encoding="UTF-8" standalone="yes"?" and not the response header... so, my current issue is regarding the response header, and in particular content-type to transform from: application/xml;charset=iso-8859-1 to application/xml;charset=utf-8.

Anyway thanks for your support.

[Kishore_Kumar_]

Hi @davidef34326447 ,

Ok. Not sure then, Is it causing any issue due to this charset ? If you still need it but not able to achieve via code, force charset at the dispatcher level. Something like below but more specific to your XMLs.

<LocationMatch "\.(?i:xml)$">
  ForceType application/xml
  Header set Content-Type application/xml;charset=utf-8
</LocationMatch>

[davidef34326447]

" Is it causing any issue due to this charset ? " yeah i think, in particular, in the JCR i have saved the char €, and in the XML a receive the char ?.

I think that the issue is related to the response content type.

Any other suggest?

[Kishore_Kumar_]

hi @davidef34326447 ,

Have you checked the dispatcher level fix for content type which I mentioned above ? Is not working ?  

[davidef34326447]

Not yet. Before to ask at client the dispatcher change, i would better understand possible other solution. As per now, in localhost (with author only), i'm receiving the issue above.

[Jörg_Hoh]

I would ask on the sling list, as the Sling Model Exporter is pure Sling. Maybe the developers there can you give you a hint into the right direction.

[Kishore_Kumar_ · Accepted solution]

Hi @davidef34326447  / @Jörg_Hoh ,

I have tried to check this issue. When i was investigating found that, earlier for application/json also it defaulted to charset=iso-8859-1 and later it was fixed.

https://issues.apache.org/jira/browse/SLING-7344 

https://github.com/apache/sling-org-apache-sling-models-impl/blob/master/src/main/java/org/apache/sl... 

And similarly we have also ticket for XML which is still Open.

https://issues.apache.org/jira/browse/SLING-8923 

Hope it gives some clarity. 

[davidef34326447]

tks @Kishore_Kumar_ , so the solutions are:

1) try to apply a similar workaround waiting the sling fix

2) try with dispatcher rule

thanks again!

[davidef34326447]

@Kishore_Kumar_ meanwhile i tried with dispatcher workaround.. and the result is like the follow: 

The xml is cutted in proximity of the special char "€". 

Sling issue in open since 2019 :|..