Container samples not working using podman

[mjbvz]

Refs #2854

repro

1. Using podman 1.9
2. Run Containers: Try a sample and select Python

Bug
The container fails to start.

Logs:

[0 ms] Start: Resolving remote
[2 ms] Start: Check Docker is running
[2 ms] Start: Run: docker info
[366 ms] Start: Run: docker volume create --label vsch.local.repository=https://github.com/Microsoft/vscode-remote-try-python --label vsch.local.repository.unique=false vsc-remote-sample
[473 ms] Start: Run: docker ps -q -a --filter label=vsch.local.repository=https://github.com/Microsoft/vscode-remote-try-python --filter label=vsch.local.repository.volume=vsc-remote-sample --filter label=vsch.local.repository.folder=vscode-remote-try-python --filter label=vsch.quality=insider
[590 ms] Start: Run: docker build -f /home/parallels/.vscode-insiders/extensions/ms-vscode-remote.remote-containers-0.113.0/scripts/volumeBootstrap.Dockerfile -t vsc-volume-bootstrap /home/parallels/.vscode-insiders/extensions/ms-vscode-remote.remote-containers-0.113.0/scripts
STEP 1: FROM alpine:3.11.2
STEP 2: RUN apk add --no-cache  nodejs  git     openssh-client  docker-cli      ;
--> Using cache 0faec7dc36e550fd8340d295a87eac456ae140b80a203267ccd6b6f0e0a2c286
STEP 3: COMMIT vsc-volume-bootstrap
--> 0faec7dc36e
0faec7dc36e550fd8340d295a87eac456ae140b80a203267ccd6b6f0e0a2c286
[731 ms] Cloning Github repository: Microsoft/vscode-remote-try-python into /workspaces/vscode-remote-try-python

[731 ms] Start: Run: docker run -d --mount src=vsc-remote-sample,dst=/workspaces,type=volume,volume-driver=local -v /var/run/docker.sock:/var/run/docker.sock vsc-volume-bootstrap sleep infinity```

And the specific error:

$ docker run -d --mount src=vsc-remote-sample,dst=/workspaces,type=volume,volume-driver=local -v /var/run/docker.sock:/var/run/docker.sock vsc-volume-bootstrap sleep infinity
Error: "src=vsc-remote-sample,dst=/workspaces,type=volume,volume-driver=local": incorrect mount format: should be --mount type=<bind|tmpfs|volume>,[src=<host-dir|volume-name>,]target=<ctr-dir>[,options]

[chrmarti]

With Docker we mount the Docker socket into a container to build the image from a volume. We need to investigate if something similar can be done with Podman. (Seeing containers/podman#4056 and containers/podman#4131 discussions.)

[chrmarti]

/cc @egamma

[Chuxel]

@egamma @chrmarti Related question: Given the challenges with the repo approach that people are experiencing yet, should we have the getting started documentation reference the local clone based approach for try repos still while we iron out the kinks?

[chrmarti]

@Chuxel Makes sense, although I wouldn't consider this Podman issue a blocker. It would be good to have a fix for the Docker case where the user gets stuck with a bad config (#2428). I think @egamma mentioned looking into fixing that, so a solution might not be too far out.

[smekkley]

I created this issue in libpod. It's technically possible to control podman from container through ssh varlink but there is a new api server. I'd say we can wait until podman api is complete, then vscode sample container can have podman inside access it through unix socket or tcp socket.
containers/podman#6219

[chrmarti]

Do we need to go through an API server? My understanding of Podman is that it works without a server, so the API server shouldn't add anything beyond giving access to the local libpod. Maybe we can access that from the container directly if we give the container the required privileges.

The reason we need this is that we want to build a Docker image from the sources we clone into a Docker volume. The container for doing this is temporary.

[smekkley]

API is just a way to get out of podman container to do what the current docker solution in vscode is basically doing, it's not actually a container in container. This is already supported by varlink or api(in the future) in podman.

If building container in container is the only requirement, that's also supported but you have to use buildah with chroot isolation mode with vfs inside podman.
This has been supported for a while. It can be done inside rootless podman or docker as long as buildah is present inside the container.

[smekkley]

I wonder if there has been any decision made on this topic.
Mounting docker socket is really bad imo. I think that should be solved first and then support podman properly.