Spring-data-mongodb connect to multiple databases in one Mongo instance

Question

I am using the latest spring-data-mongodb (1.1.0.M2) and the latest Mongo Driver (2.9.0-RC1). I have a situation where I have multiple clients connecting to my application a

Answer 1

The spot to look at is the MongoDbFactory interface. The basic implementation of that takes a Mongo instance and works with that throughout all the application lifetime. To achieve a per-thread (and thus per-request) database usage you'll probably have to implement something along the lines of AbstractRoutingDataSource. The idea is pretty much that you have a template method that will have to lookup the tenant per invocation (ThreadLocal bound I guess) and then select a Mongo instance from a set of predefined ones or some custom logic to come up with a fresh one for a new tenant etc.

Keep in mind that MongoDbFactory usually get's used through the getDb() method. However, there are features in MongoDB that need us to provide a getDb(String name). DBRefs (sth. like a foreign key in the relational world) can point to documents an entirely different database. So if you're doing the delegation either avoid using that feature (I think the DBRefs pointing to another DB are the only places calling getDb(name)) or explicitly handle it.

From a configuration point of view you could either simply override mongoDbFactory() entirely or simply not extend the base class at all and come up with your own Java based configuration.