www/blog.bryanroessler.com/_posts/2020-05-15-podmanrun-a-simple-podman-wrapper.md

---

layout: post title: 'podmanRun' date: '2020-05-15 15:36' subtitle: A simple podman run wrapper tags:

• podman
• bash
• fedora
• containers ---

Rationale

In a previous post I demonstrated the benefits of running and developing code in containers in order to maintain a clean and predictable development environment. After using run-with-podman for several months I often ran into edge cases requiring additional argument handling. In light of this, I have simplified run-with-podman into podmanRun, a podman cli wrapper that can pass arguments directly to podman while maintaining the container management benefits of run-with-podman.

Who is podmanRun intended for?

Anyone that wants to easily run programs in ephemeral or persistent containers. Personally, I use podmanRun in order to quickly test code in different Linux distributions, automate compilation, and deploy containerized build services including preprocessors and web servers.

What does podmanRun actually do?

Not much, by design.

1. Generates a unique container name based on the --name argument passed to podman within the podmanRun --options string. If no --name is specified in the --options string, podmanRun will generate a unique container name based on the concatenated options and commands passed by the user. Thus, if any options or commands are changed, a new container will be recreated regardless if --mode=persistent was set.
2. Checks whether a container with that name already exists.
3. If no matching container was found: the --options are passed directly to podman run and the commands are executed in the new container.
4. If a matching container was found:
   • --mode=recreate will remove the existing container and run the commands in a new container using podman run with the provided --options.
   • --mode=persistent will run the commands in the existing container using podman exec and --options will be ignored.
5. By default, the container is not removed afterwards (it will only be removed upon subsequent invocations of podmanRun using --mode=recreate) to allow the user to inspect the container. Containers can be automatically removed after execution by uncommenting the requisite line in __main().

Usage

For the complete list of up-to-date options, run podmanRun --help.

podmanRun [-m MODE] [-o OPTIONS] [COMMANDS [ARGS]...] [--help] [--debug]

Options

--mode, -m MODE
    1. recreate (default) (remove container if it already exists and create a new one)
    2. persistent (reuse existing container if it exists)
--options, -o OPTIONS
    OPTIONS to pass to podman run/exec
--debug, -d
    Print debugging
--help, -h
    Print this help message and exit

podmanRun supports two modes: recreate and persistent. Recreate will always overwrite an existing container with the same name, while persistent will try to execute commands in an existing container (if found) using podman exec.

Podman options can be passed to --options as a single string to be split on whitespace or passed multiple times discretely.

Examples

Run an ephemeral PHP webserver container using the current directory as webroot:

podmanRun -o "-p=8000:80 --name=php_script -v=$PWD:/var/www/html:z php:7.3-apache"

Run an ephemeral PHP webserver container using the current directory as webroot using IDE:

podmanRun -o "-p=8000:80 --name=php_{FILE_ACTIVE_NAME_BASE} -v={FILE_ACTIVE_PATH}:/var/www/html:z php:7.3-apache"

Run an ephemeral bash script:

podmanRun -o "--name=bash_script -v=$PWD:$PWD:z -w=$PWD debian:testing" ./script.sh

Run an ephemeral bash script using IDE:

podmanRun -o "--name=bash_{FILE_ACTIVE_NAME_BASE}" \
          -o "-v={FILE_ACTIVE_PATH}:{FILE_ACTIVE_PATH}:z" \
          -o "-w={FILE_ACTIVE_PATH}" \
          -o "debian:testing" \
          {FILE_ACTIVE} arg1 arg2

Additional Info

Did you find podmanRun useful? Buy me a coffee!