docker-stats: Podman not working correctly

[akqopensystems]

This issue respects the following points:

• This is a bug, not a question or a setup/configuration issue.
• This issue is not already reported on Github (I've searched it).
• I use the latest release of the Monitoring Plugins (https://github.com/Linuxfabrik/monitoring-plugins/releases).
• I agree to follow Monitoring Plugins's Code of Conduct.

Which variant of the Monitoring Plugins do you use?

• .rpm/.deb package from repo.linuxfabrik.ch
• Compiled for Windows from download.linuxfabrik.ch
• Source Code from GitHub

Bug description

When i execute the Monitoring Check i get the following Error Message.

[root@example plugins]# ./docker-stats
Unable to compute docker info (Traceback for debugging purposes attached)

Traceback (most recent call last):
  File "/usr/lib64/nagios/plugins/./docker-stats", line 167, in main
    host_cpus = int(stdout[strpos1:strpos2])
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: invalid literal for int() with base 10: ''

Steps to reproduce - Plugin call

./docker-stats

Steps to reproduce - Data

1. Install podman, podman-docker & linuxfabrik-monitoring-plugins
2. Execute the Monitoring Check as any User

Environment

Linux host.example 6.12.0-124.21.1.el10_1.x86_64 #1 SMP PREEMPT_DYNAMIC Mon Dec 22 05:10:57 EST 2025 x86_64 GNU/Linux

[root@example ~]# podman version
Client:        Podman Engine
Version:       5.6.0
API Version:   5.6.0
Go Version:    go1.25.3 (Red Hat 1.25.3-1.el10_1.alma.2)
Git Commit:    3bf531332cf3895b4a8220532c84e5849824e9e9
Built:         Wed Dec  3 01:00:00 2025
Build Origin:  AlmaLinux Packaging Team <packager@almalinux.org>
OS/Arch:       linux/amd64

Plugin Version

docker-stats: v2025022501 by Linuxfabrik GmbH, Zurich/Switzerland

Python version

Python 3.12.12

List of Python modules

No response

Additional Information

When i change CPUs on line 165 to cpus which is the format podman gives out when using docker info.
And then execute the Monitoring Check i get:

[root@example plugins]# ./docker-stats
Emulate Docker CLI using podman. Create /etc/containers/nodocker to quiet msg.

Which is a message from podman which comes whenever a docker command is used.

If i create the file using touch /etc/containers/nodocker then the Monitoring Check is working.

[root@example plugins]# ./docker-stats
Everything is ok.

Container            ! CPU % ! Mem %
---------------------+-------+------
example_container ! 0.3   ! 0.09|'cpu'=2;;;0; 'example_container_cpu_usage'=0.3%;80;90;0;100 'example_container_mem_usage'=0.09%;80;90;0;100