Inheritance of entities/repositories [DATAREST-344]

Benjamin M opened DATAREST-344 and commented

I'd like to use inheritance for my entities. And the only way of getting it kinda working was to do the following:

@Entity
@Inheritance(strategy=InheritanceType.JOINED)
@DiscriminatorColumn(name="type")
@JsonTypeInfo(use=JsonTypeInfo.Id.NAME, include=JsonTypeInfo.As.PROPERTY, property="type")
public abstract class Message implements Identifiable<UUID> { ... }

@Entity
@DiscriminatorValue("TEXT")
@JsonTypeName("TEXT")
public class TextMessage extends Message { ... }

@Entity
@DiscriminatorValue("TODO")
@JsonTypeName("TODO")
public class TodoMessage extends Message { ... }

public interface MessageRepo extends JpaRepository<Message, UUID> { }

public interface TextMessageRepo extends JpaRepository<TextMessage, UUID> { }

public interface TodoMessageRepo extends JpaRepository<TodoMessage, UUID> { }

When I now call GET http://localhost:8080/webapp/messages I get the following output:

{
  "_links": {
    "self": { "href": "http://localhost:8080/webapp/messages{?page,size,sort}", "templated": true }
  },
  "_embedded": {
    "textMessages": [
      { ... },
      { ... }
    ],
    "todoMessages": [
      { ... }
    ]
  },
  "page": {
    "size": 20, "totalElements": 3, "totalPages": 1, "number": 0
  }
}

As you can see, there's textMessages and todoMessages within the _embedded object. So, I cannot really sort my messages.

Is there a way to get all my messages within a single array?

—

EDIT: I tried to get rid of my additional projections, but that won't work:
If I only have a @Projection for Message.class, it won't get applied when calling GET http://localhost:8080/webapp/messages?projection=summary,
BUT it does work, if it's an inherited projection: GET http://localhost:8080/webapp/messageInboxes/89cb89db-67c5-49b3-8f1f-00b63b74ca4a?projection=summary
with:

@Projection(name = "summary", types = MessageInbox.class)
public interface MessageInboxSummary {
	MessageSummary getMessage();
}

@Projection(name = "summary", types = Message.class)
public interface MessageSummary {
	String getSubject();
}

@Entity
public class MessageInbox extends Identifiable<UUID> {
	@ManyToOne
	@JoinColumn(name = "Message_id", nullable = false, updatable = false)
	Message message;
	public Message getMessage() { return message; }
}

—

EDIT 2:
I now somehow fixed it / encountered a new bug...

If I put

@RepositoryRestResource(collectionResourceRel="messages", path="messages")

on all 3 repositories it behaves like I want it to: Every kind of message is available under GET http://localhost:8080/webapp/messages and all get displayed within the same array!

But now there are 2 issues:

1. The index page displays:

{
  "_links": {
    "messages": [
      {
        "href": "http://localhost:8080/webapp/messages{?page,size,sort,projection}",
        "templated": true
      },
      {
        "href": "http://localhost:8080/webapp/messages{?page,size,sort,projection}",
        "templated": true
      },
      {
        "href": "http://localhost:8080/webapp/messages{?page,size,sort,projection}",
        "templated": true
      }
    ]
  }
}

2. if I add itemResourceRel="message" to the @RepositoryRestResource annotation on all 3 repositories, the URL GET http://localhost:8080/webapp/messages will display randomly either the TextMessages OR the TodoMessages , but never both

Affects: 2.1.1 (Dijkstra SR1)

9 votes, 16 watchers