Hi @gerrit.meier Thank you for your reply!
1
The @Index is - was - a REALLY awesome feature because the Java classes are effectively a schema for a schemaless DB and what better place to define which fields should get an index than in the schema?
Without this, it is definitely a step backwards and I have to go back abut 4 years and maintain a file of Cypher statements to drop/create indexes when deploying new app versions 
2
Also very important and missing now:
- something like onPreSave e.g. for giving each entity a UUID (in addition to the
@Id @GeneratedValue Long id) or some other calculated values - onPostSave, onPostDelete for things like updating an external index
@DomainEvents is great for some certain things but not for this (unless I am completely wrong and missing something ? but I can't see how I would get the info if the entity was created/updated/deleted).
Of course I could publish an applicationEvent EVERYWHERE I save/delete an entity but I think it would be much better (and easy to implement?) if Neo4jTemplate & Repositories published some generic Neo4j events that we can listen for (possibly enabling this feature with a @EnableNeo4jEvents).
No?
3
Importing old libs: Didn't think so, don't want to 😉
4
Regarding the bidirectional relationship: I haven't used those for years because it always caused problems with OGM and now I thought with the new SDN6 I would give it a try again. So here is a compact version of what I want to do:
public abstract class Node {
@Id @GeneratedValue @Getter private Long id;
@Version @Getter private Long version;
@CreatedDate @Getter private LocalDateTime created;
@LastModifiedDate @Getter private LocalDateTime modified;
@Getter private String uuid; // <-- see nescessary onPreSave above!
}
@Node
@Getter
@Setter
public class Page extends Node {
private String title;
...
@Relationship(type = "PAGE", direction = Relationship.Direction.INCOMING) private List<File> files = new ArrayList<>();
}
@Node
@Getter
@Setter
public class File extends Node {
@Relationship(type = "PAGE") private Page page;
private String name;
...
}
// add a new file:
Page page = pageRepo.findById(id).get();
File file = new File();
file.setPage(page);
// option 1:
fileRepo.save(file); // deletes all existing connections between page and other files
// option 2:
page.getFiles().add(file);
pageRepo.save(page); // also deletes all existing connections between page and other files
// here: only the new file is connected to the page anymore
The existing files [loaded when the page is loaded] all have a getPage() of null (!) and by saving the page [either directly or indirectly through saving the new file] deletes the existing relationships.
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