# 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 Python plugin and labeling the OCI image,
the Extraction Plugin SDK comes with three utility applications: `label_plugin`, `build_plugin` and `build_plugin_ci`.

To package a plugin, make sure that the Extraction Plugins SDK is [installed](getting_started.md#Installation), as well as Docker.
Next build and label your plugin as described in the following sections.

To verify that the image has been built, use the following command to view all local images:

```bash
docker images
```

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

## `label_plugin`

`label_plugin` is a utility to add labels to an extraction plugin image.
To label a plugin, first build the plugin image with [docker build](https://docs.docker.com/reference/cli/docker/image/build/);
for example by using one of the following commands:

```shell
docker build . -t my_plugin
docker build . -t my_plugin --build-arg https_proxy=http://your_proxy:8080
```

Next, run the `label_plugin` utility to label the build plugin container:

```shell
label_plugin my_plugin
```

This utility will briefly start your plugin using Docker, and requests the PluginInfo from the plugin.
The information from the PluginInfo will be added as [labels](https://docs.docker.com/config/labels-custom-metadata/) to the plugin image.
The result of `label_plugin` is a plugin image that can be published to a docker/OCI image registry.

## `build_plugin`

The `build_plugin` extends `label_plugin` by also taking care of the docker build command.
Use this as an one-liner to both build and label your plugin image.

To build your plugin container image you can use the following command:

```bash
build_plugin DOCKER_FILE_DIRECTORY [DOCKER_IMAGE_NAME] [DOCKER_ARGS]
```

For example:

```bash
build_plugin .
```

and to pass proxy configurations to Docker:

```bash
build_plugin . --build-arg http_proxy="$http_proxy" --build-arg https_proxy="$https_proxy"
```

This will generate a plugin image:
* The extraction plugin is added to your local image registry (`docker images`),
* Note that the variables `$http_proxy` and `$https_proxy` are put in quotes, this is needed in case they contain
  spaces,
* The image is tagged with two tags: `latest`, and your plugin version.

Arguments:
* `DOCKER_FILE_DIRECTORY`: Path to the directory containing the Dockerfile of the plugin.
* (Optional) `DOCKER\_IMAGE\_NAME`: Name of the docker image without tag. Note that docker image names cannot start with
  a period or dash. If it starts with a dash, it will be interpreted as an additional docker argument (see
  DOCKER\_ARGS). If no name is given the name defaults to `extraction-plugin/PLUGINID`, e.g.
  `extraction-plugin/nfi.nl/extract/chat/whatsapp`.
* (Optional) `DOCKER\_ARGS`: Additional arguments for the docker command, which can be as many arguments as you like.

## `build_plugin_ci`

The `build_plugin_ci` performs the same tasks as `build_plugin` except that it uses a different approach for labeling
the plugin. Not all CI/CD pipelines allow docker containers to be started and connected to, something which
`build_plugin` relies on to label the plugin correctly using the plugin info specified in the plugin. `build_plugin_ci`
uses another approach which exports the image and then parses the plugin info from this image. This way a container
does not have to be started. Therefore the advantage of `build_plugin_ci` is that it can more reliably build plugins on
CI systems. The downside of this approach is that it is slower than `build_plugin` utility. It is therefore adviced to
use `build_plugin` when developing locally to speed up the development process and to use `build_plugin_ci` when
building plugins in CI/CD pipelines.

### Requirements

To build your plugin container image using `build_plugin_ci` you have to add the following line to your Containerfile
after you have copied your plugin to the image. `build_plugin_ci` requires this to find the plugin information.

<!-- pyml disable-next-line fenced-code-language-->
```
RUN plugin_info "/app/plugin.py"
```

### Command usage

`build_plugin_ci` can be invoked as follows:

```bash
build_plugin DOCKER_FILE_DIRECTORY [--target_name DOCKER_IMAGE_NAME] [--build_agent BUILD_AGENT] [BUILD_AGENT_ARGS]
```

Other than the options provided by `build_plugin` `build_plugin_ci` also provides a `--build_agent` flag which allows a
user to choose between different build agents to build and label their plugin. Currently only docker, podman and
buildah are supported. For example:

```bash
build_plugin . --target_name my-image:1.3.5 --build_agent "podman"
```

A proxy configurations can be configured as follows:

```bash
build_plugin . --build-arg http_proxy="$http_proxy" --build-arg https_proxy="$https_proxy"
```

This will generate a plugin image:
* The extraction plugin is added to your local image registry (`docker images`),
* Note that the variables `$http_proxy` and `$https_proxy` are put in quotes, this is needed in case they contain
  spaces,
* The image is tagged with two tags: `latest`, and your plugin version.

Arguments:
* `DOCKER_FILE_DIRECTORY`: Path to the directory containing the Dockerfile of the plugin.
* (Optional) `DOCKER\_IMAGE\_NAME`: Name of the docker image without tag. Note that docker image names cannot start with
  a period or dash. If it starts with a dash, it will be interpreted as an additional docker argument (see
  DOCKER\_ARGS). If no name is given the name defaults to `extraction-plugin/PLUGINID`, e.g.
  `extraction-plugin/nfi.nl/extract/chat/whatsapp`.
* (Optional) `BUILD\_AGENT`: The build agent that should be used to build the plugin. Either docker, podman or buildah.
  Docker is the default.
* (Optional) `BUILD\_AGENT\_ARGS`: Additional arguments for the buildagent command, which can be as many arguments as
  you like.