podman ps --format '{{.Label "mylabel"}}' fails with executing "ps" at <.Label>: can't evaluate field Label in type containers.psReporter

[eriksjolund]

Issue Description

$ podman ps --format '{{.Label "mylabel"}}'
Error: template: ps:1:13: executing "ps" at <.Label>: can't evaluate field Label in type containers.psReporter
$

The same command does not fail when trying it out on docker.

Steps to reproduce the issue

Steps to reproduce the issue

1. sudo useradd test
2. sudo machinectl shell --uid test
3. podman run --rm --label mylabel=hello -q -d docker.io/library/alpine sleep inf
4. podman ps --format '{{.Label "mylabel"}}'

Describe the results you received

The command in step 4 fails and prints the error message

Error: template: ps:1:13: executing "ps" at <.Label>: can't evaluate field Label in type containers.psReporter

Describe the results you expected

I expected the command in step 4 to succeed and print

hello

podman info output

host:
  arch: amd64
  buildahVersion: 1.33.2
  cgroupControllers:
  - cpu
  - io
  - memory
  - pids
  cgroupManager: systemd
  cgroupVersion: v2
  conmon:
    package: conmon-2.1.8-2.fc39.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.1.8, commit: '
  cpuUtilization:
    idlePercent: 99.74
    systemPercent: 0.2
    userPercent: 0.06
  cpus: 16
  databaseBackend: sqlite
  distribution:
    distribution: fedora
    variant: workstation
    version: "39"
  eventLogger: journald
  freeLocks: 2047
  hostname: asus
  idMappings:
    gidmap:
    - container_id: 0
      host_id: 50192
      size: 1
    - container_id: 1
      host_id: 67744801
      size: 1000000
    uidmap:
    - container_id: 0
      host_id: 50192
      size: 1
    - container_id: 1
      host_id: 67813730
      size: 1000000
  kernel: 6.6.4-200.fc39.x86_64
  linkmode: dynamic
  logDriver: journald
  memFree: 5928484864
  memTotal: 7686619136
  networkBackend: netavark
  networkBackendInfo:
    backend: netavark
    dns:
      package: aardvark-dns-1.8.0-1.fc39.x86_64
      path: /usr/libexec/podman/aardvark-dns
      version: aardvark-dns 1.8.0
    package: netavark-1.8.0-2.fc39.x86_64
    path: /usr/libexec/podman/netavark
    version: netavark 1.8.0
  ociRuntime:
    name: crun
    package: crun-1.12-1.fc39.x86_64
    path: /usr/bin/crun
    version: |-
      crun version 1.12
      commit: ce429cb2e277d001c2179df1ac66a470f00802ae
      rundir: /run/user/50192/crun
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +LIBKRUN +WASM:wasmedge +YAJL
  os: linux
  pasta:
    executable: /usr/bin/pasta
    package: passt-0^20231119.g4f1709d-1.fc39.x86_64
    version: |
      pasta 0^20231119.g4f1709d-1.fc39.x86_64
      Copyright Red Hat
      GNU General Public License, version 2 or later
        <https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>
      This is free software: you are free to change and redistribute it.
      There is NO WARRANTY, to the extent permitted by law.
  remoteSocket:
    exists: false
    path: /run/user/50192/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-1.2.2-1.fc39.x86_64
    version: |-
      slirp4netns version 1.2.2
      commit: 0ee2d87523e906518d34a6b423271e4826f71faf
      libslirp: 4.7.0
      SLIRP_CONFIG_VERSION_MAX: 4
      libseccomp: 2.5.3
  swapFree: 7686057984
  swapTotal: 7686057984
  uptime: 0h 38m 50.00s
  variant: ""
plugins:
  authorization: null
  log:
  - k8s-file
  - none
  - passthrough
  - journald
  network:
  - bridge
  - macvlan
  - ipvlan
  volume:
  - local
registries:
  search:
  - registry.fedoraproject.org
  - registry.access.redhat.com
  - docker.io
  - quay.io
store:
  configFile: /home/test695/.config/containers/storage.conf
  containerStore:
    number: 1
    paused: 0
    running: 1
    stopped: 0
  graphDriverName: overlay
  graphOptions: {}
  graphRoot: /home/test695/.local/share/containers/storage
  graphRootAllocated: 407822663680
  graphRootUsed: 388686446592
  graphStatus:
    Backing Filesystem: xfs
    Native Overlay Diff: "true"
    Supports d_type: "true"
    Supports shifting: "false"
    Supports volatile: "true"
    Using metacopy: "false"
  imageCopyTmpDir: /var/tmp
  imageStore:
    number: 2
  runRoot: /run/user/50192/containers
  transientStore: false
  volumePath: /home/test695/.local/share/containers/storage/volumes
version:
  APIVersion: 4.8.1
  Built: 1701777650
  BuiltTime: Tue Dec  5 13:00:50 2023
  GitCommit: ""
  GoVersion: go1.21.4
  Os: linux
  OsArch: linux/amd64
  Version: 4.8.1

Podman in a container

No

Privileged Or Rootless

Rootless

Upstream Latest Release

Yes

Additional environment details

Additional environment details

Additional information

It works when using docker.

$ docker run --rm --label mylabel=hello -q -d docker.io/library/alpine sleep inf
d180a9de004113adfc1c6b72da027ac8416a57d64ac884a6abf8bc61dfb42eba
$ docker ps --format '{{.Label "mylabel"}}'
hello
$ rpm -qf /usr/bin/docker
moby-engine-24.0.5-1.fc39.x86_64

Side note 1:
In a more realistic scenario you would probably like to filter the containers

$ docker ps --filter label=mylabel --format '{{.Label "mylabel"}}'
hello

Side note 2:
I found this issue when looking at the issues in the nerdctl project. I checked if Podman had a similar issue as

• nerdctl ps -a --filter label=io.x-k8s.kind.cluster --format '{{.Label "io.x-k8s.kind.cluster"}}' behaviour is inconsistent with docker containerd/nerdctl#2598

After that I found a similar old Podman issue from 2018:

• podman ps can't be formatted by Label, but only by Labels #1729
  that was closed.

Long time has gone since 2018. Maybe the issue is more relevant now?
Feel free to close this issue if it's of low priority.