how should migrate my DBRef fields with mongock? - mongodb

Question

I have a problem with migrating an entity which has DBRef fields. If I change any field in this entity, my DBRefs are gone. What should I do?
Query query = new Query();
List<Criteria> criteriaList = new ArrayList<Criteria>();
criteriaList.add(Criteria.where("created").exists(false));
criteriaList.add(Criteria.where("updated").exists(false));
query.addCriteria(new Criteria().orOperator(criteriaList.toArray(new Criteria[criteriaList.size()])));
List<Asset> results = mongoTemplate.find(query, Asset.class);
results.forEach(asset -> {
asset.setCreated(asset.getCreatedBy().getCreated());
mongoTemplate.save(asset);
});

Answer 1

in summary, its problem is the MongoTemplate. mongoTemplate.save(...) creates a new entity and saves it to DB. As a consequence, if you want to change/update a field in your entity, you should use mongoTemplate.updateFirst(...). My solution is as the following.
public void createAssetCreateOrUpdateDateIfNot(MongockTemplate mongockTemplate) {
MongoTemplate mongoTemplate = mongockTemplate.getImpl();
Query queryGetAssetsCreatedOrUpdatedIsNot = new Query();
List<Criteria> criteriaList = new ArrayList<Criteria>();
criteriaList.add(Criteria.where("created").exists(false));
criteriaList.add(Criteria.where("updated").exists(false));
queryGetAssetsCreatedOrUpdatedIsNot
.addCriteria(new Criteria().orOperator(criteriaList.toArray(new Criteria[criteriaList.size()])));
List<Asset> results = mongoTemplate.find(queryGetAssetsCreatedOrUpdatedIsNot, Asset.class);
if (results.size() > 0) {
for (Asset asset : results) {
Date createdDate = (asset.getCreatedBy().getCreated() != null)
? asset.getCreatedBy().getCreated()
: new Date();
Date updateDate = (asset.getModifiedBy().getCreated() != null)
? asset.getModifiedBy().getCreated()
: new Date();
Query queryGetAssetViaId = new Query();
queryGetAssetViaId.addCriteria(Criteria.where("id").is(asset.getId()));
Update update = new Update()
.set("created", createdDate)
.set("updated", updateDate);
mongoTemplate.updateFirst(queryGetAssetViaId, update, Asset.class);
}
}
}