Just helped a junior setup dockertest on a new service, interested in checking this out. Are you familiar with test containers or dockertest? How would you compare pgtestdb. We use postgres/pgx.
One massive advantage of pgtestdb compared to using dockertest on its own is that it handles running migrations for you in a very efficient way that amortizes the cost to zero as the number of tests trends to infinity. This should be much faster than naively creating a new database and re-running the migrations for each test.
I happen to recommend using docker-compose over dockertest out of some slight personal preference that is one part separation of concerns (it's weird to me to have the test code handle the state of the postgres container), one part developer-experience related (it's nice for devs to be able to easily manage their postgres server instance with existing docker tools outside of golang code), one part infra related (it's nice to be able to use any method to provide and manage the postgres server, particularly in CI), and one part totally arbitrary.
For migrations we have a built in house tool, but looks like we just need to satisfy the interface and we should be good to use our tool. Any tips on writing a migrator that won't be obvious?
Yeah, in some cases (devcontainer) we are using docker-compose to for the dev/pg/other systems and dockertest with docker in docker, to spin up the ephemeral pg instance for tests. It works fine, but is a little bit more complicated than I would like it.
Want to see if there's any speed improvements and better separation if we switch to pgtestdb. The transaction approach has worked well but on some larger integration tests I have seen some conflicts due to our test fixture ids.
One other nice thing about pgtestdb is that you can run all your tests in parallel, and if a test fails the related db will be left up for you to connect to via psql (helps a lot with debugging.) Compared to your transaction setup, the only data in the db will be from the test that failed.