Prior to Spring Data MongoDB 1.9.0-RELEASE, I was able to create a MongoTemplate object as follows:
new MongoTemplate(client, dbName, credentials). Upon upgrading, this constructor no longer works, giving an error to use MongoCredential instead. However, there is no similar MongoTemplate constructor that uses MongoCredential. It appears that the only way to specify credentials now is when constructing the MongoClient object.
However, since my app is multitenant on the database level, this doesn't work because it does not allow for additional credentials to be added after construction (meaning MongoTemplates cannot be created dynamically). It also is not ideal because if any of the credentials in the list are bad, none of the database connections work, as opposed to just the one with bad credentials.
I also do not want to create a new MongoClient instance for each database. From what I understand, doing so would create a new connection for each database rather than letting MongoClient manage a connection pool, which is ultimately not sustainable since Mongo only allows a finite number of connections.
Do I have any options here besides continuing to use the outdated library?
What I ended up doing is creating a single user in the admin database that has access to all of the databases that I need (achieved via the roles array). I create one MongoClient, authorizing as that user against the admin database. Then I am able to create MongoTemplate objects dynamically without issue, because the user I'm authorized as hasreadWrite permissions on those databases.