Transaction never finished Neo4j - spring-mvc

Question

I have a method which should create a sub-graph defined this way:
#Transactional
public Post createAndLink(Appuser appuser, Post post, String linkTo) {
Post savedPost = null;
if(post != null && appuser != null){
post.setCreatedBy(appuser);
if(post.getId() == null && post.getId() == ""){
post.setId("IND"+GenerateUUID.getUUID());
}
System.out.println(">>> Id created : "+post.getId());
//Date check
String d = post.getDate();
if(d != null && d.length() == 11 && ConversionUtils.isNumeric(d.substring(0, 4))
&& ConversionUtils.isNumeric(d.substring(5, 7)) && ConversionUtils.isNumeric(d.substring(8, 10))){
if(!ConversionUtils.isPastDate(d)){
System.out.println("Cannot save post with date after today");
return null;
}
}
System.out.println(">>> Date created : "+post.getDate());
//People check
Set<People> people = new HashSet<People>();
if(post.getPeople() != null){
for(People p : post.getPeople()){
People pFromDb = peopleService.findById(p.getId());
people.add(pFromDb != null ? pFromDb : new People("PPL"+GenerateUUID.getUUID(), p.getName()));
}
post.setPeople(people);
}
System.out.println(">>> People created : "+post.getPeople());
//Place check
if(post.getPlace() != null){
Place pFromDb = placeService.findById(post.getPlace().getId());
post.setPlace(pFromDb != null ? pFromDb : new Place(post.getPlace().getId()));
}
System.out.println(">>> Place created : "+post.getPlace());
System.out.println("Post checking OK.");
savedPost = repository.findById(linkTo);
if(savedPost != null){
Set<Post> linked = new HashSet<Post>();
linked.add(savedPost);
post.setLinkedPosts(linked);
}
template.save(post);
System.out.println("=====> [saveWithUser]: Saved OK!");
}
return savedPost;
}
When I call this method within a loop, sometimes it gets stuck (in one of the iterations) in the execution of template.save(post).
The same behaviour is observed when I call this method unitarily from a GUI.
PS: The findBy methods are not transactional.
I'm stuck on it since 2 weeks and I can't find a way to solve it :/
Thanks for any feedback.
Edit 1:
Logs produced by the method:
>>> Id created : IND6f770750-7834-40ae-a07e-fc81bbb3c657
>>> Date created : 2009Y09M20D
>>> People created : [People [id=PPLaf830449-b15c-4c71-b706-abd11492b825, name=Mary], People [id=PPLdf53d2c7-06b1-49c8-9b69-3b765d9b2ee6, name=Laptop]]
>>> Place created : Place [id=2918548, name=null]
Post checking OK.
PS: The iteration before the blocked one, it shows a normal log execution but nothing created in the DB
Edit 2:
And sometimes I get this error (always during the 2nd iteration while 1st shows normal logs but writes nothing on DB):
javax.transaction.RollbackException: Tx status is: STATUS_MARKED_ROLLBACK

Answer 1

I think I found the problem (but not yet the solution)
I removed all #Transactional annotations from my service methods (controllers and repositories are not marked as Transactional).
In the method createAndLink described in the main post I added transaction this way :
if(post != null && appuser != null){
Transaction tx = template.getGraphDatabaseService().beginTx();
//I kept the same code...
//...
tx.success();
tx.close();
}
Now, when I call this method from a controller A, the tx is of type Placebo. When I call it from a controller B, the tx type is a TopLevel.
I even made a test with calling the controller A method from the controller B (like in the example below) and it worked perfectly (with a TopLevel Tx). When I do the opposite way, the Tx is Placebo.
Controller A:
#RequestMapping(value="/newandlinksimilar/{linkedTo}", method=RequestMethod.POST)
public #ResponseBody boolean createAndLinkNewSimilar(#RequestBody Post post, #PathVariable String linkedTo){
Post created = null;
Authentication auth = SecurityContextHolder.getContext().getAuthentication();
if (post!= null && !(auth instanceof AnonymousAuthenticationToken)) {
AppuserDetails userDetails = (AppuserDetails)auth.getPrincipal();
Appuser currentUser = appuserService.findByLogin(userDetails.getUsername());
created = postService.createAndLinkSimilar(currentUser, post, linkedTo);
}
return created;
}
Controller B:
#autowired
private ControllerA controllerA;
#RequestMapping("/init")
public ModelAndView init(){
//I create a new Post object "post" with dummy data
controllerA.createAndLinkSimilar(post,"XXXXXX");
//Or postService.createAndLinkSimilar(appuser,post,"XXXXXX");
return new ModelAndView("home");
}
Both tests are made from a GUI ajax call to the controller method.
I can't understand when and how Spring choose the type of the transaction?!