RevisionMetadata cannot handle RevisionTimestamp in TIMESTAMP format

[stefanzilske]

Hi folks,

I started using Hibernate Envers natively and created my own RevisonInfo and REVINFO table. I used TIMESTAMP as data type for the RevisionTimestamp and mapped it to java.util.Date, which is fine for Hibernate.

Now we are starting to use spring-data-envers and run into the following issue:

RevisionMetadata expects the RevisionTimestamp to be either an Instant, LocalDateTime Long, while Hibernate supports only Long, java.util.Date or java.sql.Date.

I could switch to long, but I would prefer to keep a readable format in the database.

Is there any way out of this? I wonder why spring-data-envers, which wraps Hibernate Envers, is supporting different types.

Cheers,
Stefan

[odrotbohm]

If you map it to a java.util.Date, shouldn't you be able to adapt it to an Instant? Are you able to provide a sample project to clarify what is not working?

[odrotbohm]

Oh, wait. Now I get you. I guess the relevant parts are missing in Spring Data Commons' AnnotationRevisionMetadata.convertToInstant(…). I wouldn't mind to see a PR that adds the necessary if-clause to convert from Date or Timestamp right away. However, we'd have to track this in Spring Data Commons.

[odrotbohm]

I've filed DATACMNS-1384. Looks pretty straight forward, I'll get right to it.

[odrotbohm]

That's fixed for Lovelace and Kay. Would you mind trying the latest snapshots?

[stefanzilske]

Definitely! Thanks for the quick reaction. I was just about forking the repo when you confirmed it's already done.

I will come back at you, as soon as I tried it.

[stefanzilske]

@olivergierke we have tried the latest snapshots and it works fine. Thank you for the quick reaction!

[odrotbohm]

Awesome, thanks for confirming.

[arvera]

Is there documetation that explains how to achieve the transformation?

[arvera]

Is there documetation that explains how to achieve the transformation?

Well I figure it out and it might worth to add it to some documentation. This is what I did for Derby:

My class looks like:

public class MyRevisionInfo implements Serializable{
...	
   @RevisionTimestamp
   @Column (name="REVTSTMP")
   private Instant timestamp;
...
   @Transient
   public Date getRevisionDate() {
		 return new Date(timestamp.toEpochMilli());
   }
   
   public Instant getTimestamp() {
        return timestamp;
   }

   public void setTimestamp(Instant timestamp) {
        this.timestamp = timestamp;
   }

and my ddl looks like:

     create table REVINFO (
       REVISION bigint generated by default as identity,
       REVTSTMP timestamp,
       USERNAME varchar(255),
       primary key (REVISION)
   );