'--infra-command' parameter in pod create not working as expected

[KKoukiou]

/kind bug

Description

Running the following command podman pod create --infra-image alpine --infra-command 'sleep 1000' --name pod-1
will create pod-1 with and infra container whose command is /bin/bash and not sleep 1000 as specified in the arguments.

I would expect that the infra container created would now have an EntryPoint equal to sleep 1000`. Instead I get the following configuration.

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

[root@localhost ~]# podman ps --all
CONTAINER ID  IMAGE                            COMMAND  CREATED         STATUS                         PORTS   NAMES
...
a7b81b9a77e3  docker.io/library/alpine:latest  /bin/sh  3 minutes ago   Exited (0) About a minute ago          23a396950741-infra

[root@localhost ~]# podman pod inspect pod-1
{
    "Id": "23a3969507419bbe8a095d3313e79286e66a9ddd57bcb1ee125318d4ad4b02bd",
    "Name": "pod-1",
    "Created": "2020-07-31T07:53:18.994608342-04:00",
    "CreateCommand": [
        "podman",
        "pod",
        "create",
        "--infra-image",
        "alpine",
        "--infra-command",
        "sleep 1000",
        "--name",
        "pod-1"
    ],
    "State": "Stopped",
    "Hostname": "pod-1",
    "CreateCgroup": false,
    "CgroupParent": "machine.slice",
    "CgroupPath": "machine.slice/machine-libpod_pod_23a3969507419bbe8a095d3313e79286e66a9ddd57bcb1ee125318d4ad4b02bd.slice",
    "CreateInfra": false,
    "InfraContainerID": "a7b81b9a77e30c7c783dddf9af11b1f617b84eef12f36115053dd469270a4e80",
    "SharedNamespaces": [
        "ipc",
        "net",
        "uts"
    ],
    "NumContainers": 2,
    "Containers": [
        {
            "Id": "9db93de08b23d0fb2814cae0df653e75207e747638fe0d7a1cd00e3764640fc7",
            "Name": "test-pod-1-system",
            "State": "configured"
        },
        {
            "Id": "a7b81b9a77e30c7c783dddf9af11b1f617b84eef12f36115053dd469270a4e80",
            "Name": "23a396950741-infra",
            "State": "stopped"
        }
    ]
}

Output of podman version:

2.0.2

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

podman-2.0.2-1.fc32.x86_64

[vrothberg]

In case another image is specified, we default to the image's entrypoint. I think that behaviour is sane.

However, if we specify a custom infra-command we should set it. It looks like we ignore it entirely (even without specifying a custom image).

@mheon, I'll hand this over to you as I won't be able to tackle it today. Feel free to reassign to me if you don't find time today.

s.InfraCommand = strings.Split(p.InfraCommand, " ") ... is dangerous in for string arguments such as --infra-command '/bin/tool "string argument with space". Instead we should use github.com/google/shlex.

I also noted that containers.conf doesn't account for arguments, so we could shlex the input from there as well.

It looks like there are a couple of things to unpack. We also need tests for infra-command.

[mheon]

I think what we should do if have InfraCommand and InfraArgs - InfraCommand can be the entrypoint and remains a string, and we gain the ability to set arguments for it with InfraArgs, a []string appended to the command. It's a little awkward but it keeps backwards compat.

[vrothberg]

I (weakly) prefer shlex-ing over adding InfraArgs as the latter adds more complexity: command and args could both be set in the config and in the CLI and on top we have data from the image to consider if --infra-image is specified.

[Luap99]

Why not make it compatible with podman create and accept the image as first argument and the command as 1-n args?

[mheon]

Pods don't need to have infra containers - we actually have (loose) plans to replace them with pinned namespaces in the future - so I'm hesitant to make their arguments a required part of the pod command.

[github-actions]

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

[vrothberg]

I think what we should do if have InfraCommand and InfraArgs - InfraCommand can be the entrypoint and remains a string, and we gain the ability to set arguments for it with InfraArgs, a []string appended to the command. It's a little awkward but it keeps backwards compat.

@mheon, I assigned the issue to you. I simply forgot to unassign myself before.

[mheon]

@ParkerVR PTAL

[rhatdan]

I believe this is now fixed, reopen if I am mistaken.