Allow explicitely requesting upsert for documents

[alcaeus]

ODM automatically decides whether a document should be inserted or upserted based on whether or not it has an identifier. The logic requires that the identifier is set manually before persist is called. This does not work when using custom ID generators. This is illustrated in #1422.

The best way would be to specify a storage strategy at the document level, specifying whether a document should be written using insert (default) or upsert. This would also allow supporting the $setOnInsert operator that was added in MongoDB 2.4.

Note: this is currently scheduled for the 2.0.0 milestone due to the required cleanup of collection strategies, as some strategies would not play nice when doing upserts.

[malarzm]

as some strategies would not play nice when doing upserts.

I was also thinking to allow changing collection's strategy for the upsert only, namely to use atomisSetArray during normal flush and utilize for instace addToSet during upsert.

[dbpolito]

I would love to see this too, upsert with $setOnInsert

[Steveb-p]

@alcaeus is it expected behavior then that calling persist on a new document with ID set beforehand will be upserted to MongoDB? I'm asking to know should I rely on this in my code since I'm using it for updating multiple already existing documents without loading them (they represent a state snapshot for a given time for grouped data).

[alcaeus]

Yes, that is the expected behavior at this time. We will not be changing this for 2.0 either.

[g13013]

is there any clean workaround to this issue ?

[alcaeus]

@g13013 if you are not relying on $setOnInsert, then assigning an identifier when the entity is created will work to force an upsert. If you want to use $setOnInsert, you'll have to insert data manually using the query builder.

[g13013]

@alcaeus I fixed the issue using the @PrePersist @PreUpdate hooks by calling the generator manually