[BUG] Misleading error message if user has no permission for docker socket

[jeffrson]

Description

If the user has no permission to access docker socket:

> docker ps
permission denied while trying to connect to the docker API at unix:///var/run/docker.sock

docker compose up shows a very misleading error message:

> docker compose up -d
read <pwd>: is a directory

Steps To Reproduce

Linux

docker compose version
Docker Compose version v5.1.1

obviously simple to reproduce (no docker-compose.yml, even empty directory suffices)

Compose Version

Docker Environment

Anything else?

No response

[m-alikhizar]

Hi, I'd like to work on this. I'll submit a PR.

[ndeloof]

AFAICT read <pwd>: is a directory error only appears as COMPOSE_FILE is set but doesn't point to an actual file. docker.sock permission is unrelated. Your fix won't help to close this issue. Anyway, this is relevant to test the API client before first use, I suggest apiClient() to use a sync.Once block to ping daemon on first actual access, then errConnectionFailed will report the expected error message

[ndeloof]

fixed by compose-spec/compose-go#909