Symfony 4, Doctrine and AWS RDS read replica usage

I'm about to embark on using RDS with a master read/write and slave read-only setup.

I've read about the Doctrine MasterSlaveConnection type.

However, there will be some endpoints I create that I would like to use the read-only replica (most of my GET endpoints) and some will need to write data (PUT, PATCH, DELETE endpoints).

I'm also using API Platform.

What is the best way of achieving this in Symfony 4 and Doctrine 2?