Using local and non-docker-hub registries

[mskyttner]

This might be more of a question since I haven't found anything in the vignettes or when searching through issues. My use case is to work with a) locally built containers and b) containers hosted on the github container registry (see https://www.docker.com/blog/docker-support-for-the-new-github-container-registry/).

a) To run a container residing only in the local registry I have tried:

docker <- stevedore::docker_client()
potrace <- docker$container$run(image = "image/slug:localregistry", cmd = "potrace -h", rm = TRUE, tty = TRUE)

This gives: Error: OCI runtime create failed: container_linux.go:349: starting container process caused "exec: "potrace -h": executable file not found in $PATH": unknown

Regardless of the parameter tty I get the same message. Am I doing it wrong? I'm trying to replicate what I have working at the bash prompt when I do this:

docker run --rm image/slug:localregistry potrace -h

b) How do I configure the client to use the github container registry for pulling images?