This repo is very similar to Ecto.Repo but instead of being a module to be extended, it's a module meant to be used to map tenants to database instances in case you are sharding tenants. It also provides feature parity with Ecto.Repo by using meta-programming and adding the prefix into the options.

A Note on Replicas

Please note that we did not include some functions in the tenant to repo mapper since they tend to map to different server instances. If you have a repo and different DB instances which are replicated, then you could risk starting a transaction on one server and closing it on another. To avoid this, we simply do not allow you (it's a sneaky problem) and instead recommend to use a little less sugar. Here's an example if Ecto.Repo.stream/3 and Ecto.Repo.transaction/2 were implemented:

# Grab a stream from `Repo.Foo.Replica1`
stream = Condo.Repo.stream(User, :foo)

# Start a transaction on `Repo.Foo.Replica2`
Condo.Repo.transaction(fn -> Enum.to_list(stream) end, :foo)

Instead, Condo recommends that you lookup the repo first and then run your transactions:

repo = Condo.Repo.repo(:foo)
stream = repo.stream(User, prefix: Condo.prefix(:foo))
repo.transaction(fn -> Enum.to_list(stream) end, prefix: Condo.prefix(:foo))

This is far more safe and allows you to scale to read replicas in the future. Functions from Ecto.Repo not implemented:

• checkout/2
• in_transaction?/0
• rollback/1
• stream/2
• transaction/2