Do you need some help with managing GKE and CloudSQL from pulumi or you’re asking how you can deploy PgBouncer within k8s cluster?

What is not clear to me is how to specify the correct connection string from PgBouncer to Cloud SQL. The official documentation recommends to connect to Cloud SQL using Cloud SQL Auth proxy and load it as sidecar in the same pod as, I assume, PgBouncer.

Does it mean that the connection will look like this: microservice -> PgBouncer -> Cloud SQL Auth proxy -> Cloud SQL?

In terms of hosts and ports, is it going to be something like: microservice: pgbouncer-service:6432 (example port) -> localhost:5432 -> <cloud-sql-connection-stringg>:5432 -> Cloud SQL?

… or is there a simpler way to deploy PgBouncer to GKE?

It’s possible to setup CloudSQL and GKE to communicate over private IP address. In that case, you can simply get rid of cloud sql proxy.

but the way you described it seems legit as well. That’s how I did it back in time when private connections were not available in GCP (although without PgBouncer)