如何在spring-data-rest中防止relTargetType的json输出？

Question

I'm creating a @RepositoryRestResource and export it as rest service as follows:

@RepositoryRestResource(collectionResourceRel = "myContent", path = "myContent")
public interface MyContentRepository extends PagingAndSortingRepository<MyContentEntity, Long> {

}

Problem: when I request the content, I'm getting the following excerpt:

  "content" : [ {
    "value" : [ ],
    "rel" : null,
    "collectionValue" : true,
    "relTargetType" : "com.domain.MyContentEntity"
  } ],

Question: how can I prevent to expose the relTargetType package and "real" domain name?

Answer 1

In your POJO:

If you don't want relTargetType in the JSON at all:

@JsonIgnore
public String getRelTargetType() {
    return relTargetType;
}

If you just want to hide the package:

public String getRelTargetType() {
    return relTargetType.split("\\.")[2];
}

If you want to hide the package and return a different domain name:

public String getRelTargetType() {
    return "AlteredDomainName";
}

Answer 2

I'm not familiar with Spring Rest Data, but as far as I can tell it uses Jackson for its JSON handling.

If that is indeed the case, I would suggest that your situation calls for the use of Mix-in annotations , which are intended for controlling the serialization of classes that cannot be modified.

First create a simple mix-in class with the JsonIgnoreType annotation set.

@JsonIgnoreType
public class OmitType {}

Next up, register the mix-in in the ObjectMapper instance used. As far as I can tell, you get access to it in Spring Rest Data by following these instructions :

To add your own Jackson configuration to the ObjectMapper used by Spring Data REST, override the configureJacksonObjectMapper method. That method will be passed an ObjectMapper [...]

In the configureJacksonObjectMapper method, register the mix-in with the unwanted type like this:

objectmapper.addMixIn(RelTargetType.class, OmitType.class);

Note that RelTargetType.class is just a guess. Change to whatever type the field actually contains. This should make Jackson ignore fields of that specific type whenever it encounters them.

Added:

In case the relTargetType field in MyContentEntity is actually just a string field, the mix-in could be changed to the following instead:

public abstract class OmitType {
    @JsonIgnore
    public abstract String getRelTargetType();
}

And registering it should be changed to:

objectmapper.addMixIn(MyContentEntity.class, OmitType.class);