create systemd unit files

[Klaas-]

Hi,
I am interested in implementing systemd units for containers and especially pods, would you see that as part of podman_container or should that go into a new module?

I already looked into the podman command, I think podman generate systemd needs another output format for it to be easily parseable in python, but I would welcome any suggestions.

Greetings
Klaas

[sshnaidm]

@Klaas- , I think we'd better to make it as a separate module. Even if we integrate it into podman_container, it's always good to have it separately in case you need just to generate files for existing containers.
You can just parse output of command, it's actually the text of systemd file, like we do here with version for example: https://github.com/containers/ansible-podman-collections/blob/master/plugins/modules/podman_container.py#L1777-L1778

def _get_podman_version(self):
      # pylint: disable=unused-variable
      rc, out, err = self.module.run_command(
          [self.module.params['executable'], b'--version'])
      if rc != 0 or not out or "version" not in out:
          self.module.fail_json(msg="%s run failed!" % self.module.params['executable'])
      return out.split("version")[1].strip()

[Klaas-]

@sshnaidm using the stdout output works for a single container, my main focus for now is getting awx to work (and that is a pod with multiple containers). I looked at the output, that's a concatination of the multiple service files without a real seperator if I did not misread the output :) I was going to suggest to add a json output or something like that but go is not really my language :D

[sshnaidm]

@Klaas- you're right, there is no visible delimiter. We can try to rely on comments, which are first lines in the file like:

# pod-mypod.service
# autogenerated by Podman 1.8.1
# Wed Apr  8 22:16:40 IDT 2020

But it'll be a guess.
Can you point me please to pod configuration with AWX?
I'm not sure Podman team will adopt JSON for a file output, might be challenging with multiline and indentation. But for a visible and well defined delimiter I think would be reasonable to ask.

[Klaas-]

@sshnaidm I'm currently working on getting the current version to work ikke-t/awx_pod#7 is what I'm using for now, but I want to replace the podman role with something working smoother :)

[sshnaidm]

@Klaas- hi, any work in progress about generation of systemd files?
I think to start systemd files generation for pods and containers, also play_kube functionality. I wonder if you made something or maybe have use cases for this. I think it's worth to add automatic generation of systemd units and their installation.

[Klaas-]

@sshnaidm hi, no I haven't worked on it more. For now I my primary usecase is the awx_pod and that is using https://github.com/ikke-t/podman-container-systemd - I would like to see this implemented here but I haven't found the time yet :D

[Luap99]

I have added the --format json option in containers/podman#7329. This will be included in podman v2.1.

$ podman generate systemd --format json ad352b0cb348
{
 "container-ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667": "# container-ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667.service\n# autogenerated by Podman 2.1.0-dev\n# Mon Sep 14 20:26:09 CEST 2020\n\n[Unit]\nDescription=Podman container-ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667.service\nDocumentation=man:podman-generate-systemd(1)\nWants=network.target\nAfter=network-online.target\n\n[Service]\nEnvironment=PODMAN_SYSTEMD_UNIT=%n\nRestart=on-failure\nExecStart=/home/paul/go/src/github.com/containers/libpod/bin/podman start ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667\nExecStop=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667\nExecStopPost=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667\nPIDFile=/run/user/1000/containers/overlay-containers/ad352b0cb348cd28d097dae8902a444e5fca1aacd834698018aa482437b8f667/userdata/conmon.pid\nKillMode=none\nType=forking\n\n[Install]\nWantedBy=multi-user.target default.target\n"
}

Output for a pod:

$ bin/podman generate systemd --format json pod
{
 "container-6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268": "# container-6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268.service\n# autogenerated by Podman 2.1.0-dev\n# Mon Sep 14 20:37:28 CEST 2020\n\n[Unit]\nDescription=Podman container-6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268.service\nDocumentation=man:podman-generate-systemd(1)\nWants=network.target\nAfter=network-online.target\nBindsTo=pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\nAfter=pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\n\n[Service]\nEnvironment=PODMAN_SYSTEMD_UNIT=%n\nRestart=on-failure\nExecStart=/home/paul/go/src/github.com/containers/libpod/bin/podman start 6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268\nExecStop=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268\nExecStopPost=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268\nPIDFile=/run/user/1000/containers/overlay-containers/6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268/userdata/conmon.pid\nKillMode=none\nType=forking\n\n[Install]\nWantedBy=multi-user.target default.target\n",
 "container-a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a": "# container-a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a.service\n# autogenerated by Podman 2.1.0-dev\n# Mon Sep 14 20:37:28 CEST 2020\n\n[Unit]\nDescription=Podman container-a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a.service\nDocumentation=man:podman-generate-systemd(1)\nWants=network.target\nAfter=network-online.target\nBindsTo=pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\nAfter=pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\n\n[Service]\nEnvironment=PODMAN_SYSTEMD_UNIT=%n\nRestart=on-failure\nExecStart=/home/paul/go/src/github.com/containers/libpod/bin/podman start a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a\nExecStop=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a\nExecStopPost=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a\nPIDFile=/run/user/1000/containers/overlay-containers/a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a/userdata/conmon.pid\nKillMode=none\nType=forking\n\n[Install]\nWantedBy=multi-user.target default.target\n",
 "pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f": "# pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\n# autogenerated by Podman 2.1.0-dev\n# Mon Sep 14 20:37:28 CEST 2020\n\n[Unit]\nDescription=Podman pod-9c478a337035daffc68d0a0618bfce0ec97ff9612a3face59302ad51b539101f.service\nDocumentation=man:podman-generate-systemd(1)\nWants=network.target\nAfter=network-online.target\nRequires=container-6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268.service container-a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a.service\nBefore=container-6ae41af23d0292450901204a29227e0420c081a1a71b89429142d5aa719a5268.service container-a3aeb4ccd27b3b66a5786982da65da9ee59a9c1da1e70951ce99b53a0542361a.service\n\n[Service]\nEnvironment=PODMAN_SYSTEMD_UNIT=%n\nRestart=on-failure\nExecStart=/home/paul/go/src/github.com/containers/libpod/bin/podman start 7443127611f85a0f2fbe7a5a33d94b262717e040295a1c33134775b991240b30\nExecStop=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 7443127611f85a0f2fbe7a5a33d94b262717e040295a1c33134775b991240b30\nExecStopPost=/home/paul/go/src/github.com/containers/libpod/bin/podman stop -t 10 7443127611f85a0f2fbe7a5a33d94b262717e040295a1c33134775b991240b30\nPIDFile=/run/user/1000/containers/overlay-containers/7443127611f85a0f2fbe7a5a33d94b262717e040295a1c33134775b991240b30/userdata/conmon.pid\nKillMode=none\nType=forking\n\n[Install]\nWantedBy=multi-user.target default.target\n"
}

[dan-m8t]

any updates here? Right now I'm using the shell module to create systemd files.

[soulmanos]

I'd be keen for this functionality too, likewise using shell

[sshnaidm]

This is an open source project, you're welcome to send a patch.