RESTEasy: #Form deserialization issue in a #POST method - json

Question

Here's a puzzle!
In a simple POST implementation:
#POST
#Consumes(MediaType.APPLICATION_JSON)
public Response promote(#Form PromotionForm promotion) {
return Response.status(Response.Status.OK)
.entity(promotion.toString())
.build();
}
the argument passed to me does not have values set:
PromotionForm{name='null', csid=null}
But in debugger I can see that the request server received has the values in its input stream:
new BufferedReader(new InputStreamReader(
((HttpServletInputMessage) request).getInputStream())).readLine()
// returns: {"name":"form","csid":123}
After some debugging I could see that RESTEasy tries to derive arguments for the POST method call:
args[i++] = extractor.inject(input, response);
Which leads to FormInjector code:
propertyInjector.inject(request, response, target);
And eventually to FormParamInjector:
List<String> list = request.getDecodedFormParameters().get(paramName);
But request.getDecodedFormParameters() size is 0. RESTeasy does not try to read
anything from the requests' input stream for some reason.
Any ideas how I can make RESTeasy populate PromotionForm object correctly?
More information below.
Thanks for all you answers and comments in advance.
The client call is:
final PromotionForm form = new PromotionForm();
form.setName("form");
form.setCsid(123L);
final Response response = new ResteasyClientBuilder()
.disableTrustManager()
.build()
.target(targetField.getValue())
.request(requestField.getValue())
.cookie(cookieNameField.getValue(), cookieValueField.getValue())
.buildPost(Entity.entity(form, MediaType.APPLICATION_JSON_TYPE))
.invoke();
The PromotionForm:
import javax.ws.rs.FormParam;
public class PromotionForm {
#FormParam("name")
private String name;
#FormParam("csid")
private Long csid;
// setters & getters omitted
Dependencies:
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>resteasy-jaxrs</artifactId>
<version>3.0.4.Final</version>
</dependency>
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>resteasy-jackson2-provider</artifactId>
<version>3.0.4.Final</version>
</dependency>
<!-- scannotation & resteasy-client ommitted -->
web.xml snippet:
<context-param>
<param-name>resteasy.scan</param-name>
<param-value>true</param-value>
</context-param>
<servlet>
<servlet-name>resteasy-servlet</servlet-name>
<servlet-class>org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>resteasy-servlet</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
<context-param>
<!--If the url-pattern for the Resteasy servlet-mapping is not /*-->
<param-name>resteasy.servlet.mapping.prefix</param-name>
<param-value>/rest</param-value>
</context-param>

Answer 1

Your method says that it consumes application/json. But the PromotionForm-class has #FormParam-annotations, which as the name implies, consumes form data.
To fix this, do one of the following:
Try to post form data instead of json. And change your #Consumes-annotation value to application/x-www-form-urlencoded
OR
Remove the #Form-annotation. Add JAXB-annotations on PromotionForm, so that the json data you post can be mapped to the PromotionForm-class.