SpringBoot spring-boot-docker-compose doesn't create service connections when image has registry host but not project

I'm using spring-boot-docker-compose to automatically start a Postgres database before my application tests start. With this docker compose file, everything works fine:

services:
  postgres:
    image: postgres:latest
    environment:
      - 'POSTGRES_DB=mydatabase'
      - 'POSTGRES_PASSWORD=secret'
      - 'POSTGRES_USER=myuser'
    ports:
      - '5432'

But if I add the registry host in the image field, the application doesn't start because it couldn't read the information to connect to the database. This is an example that make it fails:

services:
  postgres:
    image: docker.my-company.com/postgres:latest
    environment:
      - 'POSTGRES_DB=mydatabase'
      - 'POSTGRES_PASSWORD=secret'
      - 'POSTGRES_USER=myuser'
    ports:
      - '5432'

The log show that the container started:

2025-08-27T15:56:04.917+02:00  INFO 11248 --- [           main] .s.b.d.c.l.DockerComposeLifecycleManager : Using Docker Compose file /Users/johnowl/Projects/company/application/compose.yml
2025-08-27T15:56:05.448+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Recreate
2025-08-27T15:56:05.493+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Recreated
2025-08-27T15:56:05.495+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Starting
2025-08-27T15:56:05.595+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Started
2025-08-27T15:56:05.596+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Waiting
2025-08-27T15:56:06.105+02:00  INFO 11248 --- [utReader-stderr] o.s.boot.docker.compose.core.DockerCli   :  Container application-postgres-1  Healthy
2025-08-27T15:56:06.832+02:00  INFO 11248 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data R2DBC repositories in DEFAULT mode.
2025-08-27T15:56:06.900+02:00  INFO 11248 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 65 ms. Found 2 R2DBC repository interfaces.

And then, I see this error:

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to configure a ConnectionFactory: 'url' attribute is not specified and no embedded database could be configured.

Reason: Failed to determine a suitable R2DBC Connection URL

Comment From: wilkinsona

I think this is a bug in ConnectionNamePredicate and related code. When the image name has a registry, as your does, we expect there to then be both a project and an image, but yours has only an image. The project is not required, however, as shown in the Docker Compose docs.

As a workaround, you can configure the service with a label.