It was also designed to be a drop-in replacement for Docker with similar command-line interface and everything.
Thus, it is also compatible with Docker images and configurations (i.e., Dockerfiles).
* Configuring to include =docker.io=
By default, Podman focuses on making the user concious about multiple registries outside DockerHub.
Thus, it doesn't have any by default.
You have to configure it first.
For more information, see the =podman.1= manual page and the linked pages.
Here's an incredibly simple example configuration that includes DockerHub.
#+begin_src toml
unqualified-search-registries = ['docker.io']
#+end_src
* Subcommands
Podman has Git-style command-line interface with subcommands and exclusive options.
- =build= is for building images from the configuration — e.g., ~podman build .~ will build an image from the current directory with the Dockerfile.
+ =-t, --tag [NAME]= attaches a tag to the image.
+ =-f, --file [FILE]= sets the name of the Dockerfile to be built from.
- =run= will create a container from an image.
+ =-d, --detach= will make the process run in the background.
+ =-it= will make an interactive shell.
+ =-p, --publish= exposes the port of the image to the host.
- =tag= will tag an existing image.
Useful for correcting tags for pushing into a remote registry.
- =image= is anything about interaction with images.
In fact, a lot of the subcommands presented so far are aliases with =image= being the original — e.g., =image tag= vs =tag=, =image pull= vs =pull=, =image rm= vs =rmi=.
* Examples
Podman is a big tool so it needs a big list of examples.
** Quickstart for pushing a container
As with big tools, comes with a big quickstart.
#+begin_src shell
# Builds an image from the Dockerfile of the current directory.
podman build --tag todo-list-web-app .
# List the images to see if our app image has been built.
podman image list
# Assuming the app creates an HTTP server at port 5000, we'll expose it to the host, making it accessible from there.
podman run -d -p 5111:5000 todo-list-web-app
# See if we did run a containerized version of our app.
podman container list
# Tag the image with the convention seen in Docker registry.
podman tag foodogsquared/python-helloworld:v1.0.0
# Push the image to the Docker registry (assuming you've already logged in to Docker registry).
podman push foodogsquared/python-helloworld
#+end_src
** Interactive selection of removing images
What would be an example script without something like [[id:4eb1f8b1-bc12-4a6c-8fa4-20e4c3542cf2][fzf]]?
#+begin_src bash
podman image list --format "{{.ID}} {{.Repository}} {{.Tag}}" \
