# Packaging

Extraction plugins are packaged as OCI images (also known as Docker images).
The OCI images are labeled with the PluginInfo.
To automate packaging of a Java plugin and labeling the OCI image, the Extraction Plugin SuperPom has been configured to automate this for you.

If your project uses the Extraction Plugin SuperPom (see [Prerequisites](prerequisites.md)), Packaging an extraction plugin is handled by Maven.
To package your plugin into a container image, the following command can be used:

```bash
mvn package docker:build
```

This will generate a plugin image:

* The extraction plugin is added to your local image registry
(`docker images`),
* The image name is `extraction-plugin/PLUGINID`, e.g.
`extraction-plugin/nfi.nl/extract/chat/whatsapp`,
* The image is labeled with two tags: `latest`, and your plugin version.

It is possible to apply extra arguments to the docker command [as described here](http://dmp.fabric8.io/#docker:build).
For example, to specify a proxy, use the following command:

```bash
mvn package docker:build -Ddocker.buildArg.https_proxy=https://proxy:8001
```

Once your plugin is packaged, it can be published or 'uploaded' to Hansken.
See ":ref:`upload_plugin`" for instructions.

.. _java_superpom_podman:

Note: if your build environment does not have Docker available, you can use
[podman](https://podman.io/) as an alternative. Install podman on your machine
or build agent, and run the following commands _before_ invoking the
`mvn package docker:build` command:

```bash
podman system service --time=0 unix:/run/user/$(id -u)/podman/podman.sock &
export DOCKER_HOST="unix:/run/user/$(id -u)/podman/podman.sock"
```