podman-docker doesn't support --config

[coiby]

Is this a BUG REPORT or FEATURE REQUEST? (leave only one on its own line)

/kind bug

Description

podman doesn't support --config. One consequence is Github Action could fail because when using a podman-docker on a self-hosted runner.

Steps to reproduce the issue:

1. Install podman-docker (podman version 4.1.1)

2. docker --config

Describe the results you received:

$ docker --config test
Error: unknown flag: --config
See 'podman --help'

Describe the results you expected:
pod

Additional information you deem important (e.g. issue happens only occasionally):

Output of podman version:

podman version 4.1.1

Output of podman info --debug:

WARN[0000] The cgroupv2 manager is set to systemd but there is no systemd user session available 
WARN[0000] For using systemd, you may need to login using an user session 
WARN[0000] Alternatively, you can enable lingering with: `loginctl enable-linger 1001` (possibly as root) 
WARN[0000] Falling back to --cgroup-manager=cgroupfs    
host:
  arch: amd64
  buildahVersion: 1.26.1
  cgroupControllers:
  - memory
  - pids
  cgroupManager: cgroupfs
  cgroupVersion: v2
  conmon:
    package: conmon-2.1.0-2.fc36.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.1.0, commit: '
  cpuUtilization:
    idlePercent: 99.27
    systemPercent: 0.23
    userPercent: 0.5
  cpus: 1
  distribution:
    distribution: fedora
    version: "36"
  eventLogger: journald
  hostname: ci-vm-10-0-137-206.hosted.upshift.rdu2.redhat.com
  idMappings:
    gidmap:
    - container_id: 0
      host_id: 1001
      size: 1
    - container_id: 1
      host_id: 165536
      size: 65536
    uidmap:
    - container_id: 0
      host_id: 1001
      size: 1
    - container_id: 1
      host_id: 165536
      size: 65536
  kernel: 5.17.13-300.fc36.x86_64
  linkmode: dynamic
  logDriver: journald
  memFree: 159924224
  memTotal: 2064752640
  networkBackend: netavark
  ociRuntime:
    name: crun
    package: crun-1.4.5-1.fc36.x86_64
    path: /usr/bin/crun
    version: |-
      crun version 1.4.5
      commit: c381048530aa750495cf502ddb7181f2ded5b400
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +YAJL
  os: linux
  remoteSocket:
    exists: true
    path: /run/user/1001/podman/podman.sock
  security:
    apparmorEnabled: false
    capabilities: CAP_CHOWN,CAP_DAC_OVERRIDE,CAP_FOWNER,CAP_FSETID,CAP_KILL,CAP_NET_BIND_SERVICE,CAP_SETFCAP,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT
    rootless: true
    seccompEnabled: true
    seccompProfilePath: /usr/share/containers/seccomp.json
    selinuxEnabled: true
  serviceIsRemote: false
  slirp4netns:
    executable: /usr/bin/slirp4netns
    package: slirp4netns-1.2.0-0.2.beta.0.fc36.x86_64
    version: |-
      slirp4netns version 1.2.0-beta.0
      commit: 477db14a24ff1a3de3a705e51ca2c4c1fe3dda64
      libslirp: 4.6.1
      SLIRP_CONFIG_VERSION_MAX: 3
      libseccomp: 2.5.3
  swapFree: 2049175552
  swapTotal: 2064642048
  uptime: 24h 35m 46.48s (Approximately 1.00 days)
plugins:
  log:
  - k8s-file
  - none
  - passthrough
  - journald
  network:
  - bridge
  - macvlan
  volume:
  - local
registries:
  search:
  - registry.fedoraproject.org
  - registry.access.redhat.com
  - docker.io
  - quay.io
store:
  configFile: /home/test/.config/containers/storage.conf
  containerStore:
    number: 0
    paused: 0
    running: 0
    stopped: 0
  graphDriverName: overlay
  graphOptions: {}
  graphRoot: /home/test/.local/share/containers/storage
  graphRootAllocated: 21046689792
  graphRootUsed: 8748195840
  graphStatus:
    Backing Filesystem: extfs
    Native Overlay Diff: "true"
    Supports d_type: "true"
    Using metacopy: "false"
  imageCopyTmpDir: /var/tmp
  imageStore:
    number: 5
  runRoot: /run/user/1001/containers
  volumePath: /home/test/.local/share/containers/storage/volumes
version:
  APIVersion: 4.1.1
  Built: 1655303518
  BuiltTime: Wed Jun 15 10:31:58 2022
  GitCommit: ""
  GoVersion: go1.18.3
  Os: linux
  OsArch: linux/amd64
  Version: 4.1.1

Package info (e.g. output of rpm -q podman or apt list podman):

podman-4.1.1-1.fc36.x86_64

Have you tested with the latest version of Podman and have you checked the Podman Troubleshooting Guide? (https://github.com/containers/podman/blob/main/troubleshooting.md)

No

Additional environment details (AWS, VirtualBox, physical, etc.):

[vrothberg]

Thanks for reaching out, @coiby!

@containers/podman-maintainers WDYT? Supporting the flag would imply translating the dockerd config to something Podman can understand (containers.conf etc.).

[Luap99]

I think the --config flag is for the client config but you linked the server config, this should be the correct one: https://docs.docker.com/engine/reference/commandline/cli/#sample-configuration-file

[vrothberg]

Thanks for correcting, @Luap99. I agree, it should be the client config not the daemon one.

[rhatdan]

I think it would be difficult to support some of the flags. I guess we could add limited support perhaps specific to the requirements of a github action.

@coiby Do you know specifically what the github action is looking for? If we just added the flag and ignored it, would that still work in most cases?

[coiby]

@rhatdan According to https://github.com/coiby/kexec-tools/runs/7105084564?check_suite_focus=true, Github Action specify --config when logging into ghcr.io and then pulling image,

Checking docker version
Clean up resources from previous jobs
Create local container network
Starting job container
  /usr/bin/docker --config /home/test/actions-runner/_work/_temp/.docker_696612a3-8386-4209-b1f6-e04558b8d04f login ghcr.io -u coiby --password-stdin
  /usr/bin/docker --config /home/test/actions-runner/_work/_temp/.docker_696612a3-8386-4209-b1f6-e04558b8d04f pull ghcr.io/coiby/fedora:35
  Trying to pull ghcr.io/coiby/fedora:35...

Note one weird thing is /home/test/actions-runner/_work/_temp/.docker_696612a3-8386-4209-b1f6-e04558b8d04f is empty.

If I simply ignore --config in /usr/bin/docker,

#!/usr/bin/sh
[ -e /etc/containers/nodocker ] || \
echo "Emulate Docker CLI using podman. Create /etc/containers/nodocker to quiet msg." >&2
if [[ "$1" == --config ]]; then
        shift 2
fi

exec /usr/bin/podman "$@"

Github Action could continue.

[github-actions]

A friendly reminder that this issue had no activity for 30 days.

[rhatdan]

I have no idea how Podman could use that config file. Bottom line the simplest thing to do is add the option and then ignore it.

[github-actions]

A friendly reminder that this issue had no activity for 30 days.