How to install plugins into a NOMAD Oasis¶

Plugins allow the customization of a NOMAD deployment in terms of which apps, normalizers, parsers and schema packages are available. In order for these customization to be activated, they have to be installed into an Oasis.

Oasis is controlled and run through a docker-compose.yaml file, which specifies the different software services and how they interact. Some of these services are using a Docker image that contains the actual NOMAD software. It is in this image where we will need to install any additional plugins with pip install.

The following sections contain some alternatives for achieving this, with the first option being the preferred one.

Option 1: Create a new customized NOMAD Oasis distribution with your plugins¶

When initially starting to create a customized NOMAD Oasis distribution, it is strongly advised that you create a GitHub repository to persist your work, collaborate with coworkers and also to automate the building and distribution of your custom image. To streamline this process, we have created a GitHub template repository that helps with all of this. It can do the following for you:

Plugins are controlled with a simple plugins.txt file where it is easy to install plugins from PyPI, Git repositories, local files, etc.
The automatic pipeline will create a new Docker image for your Oasis. This image will also be stored on GitHub servers.
Initial modifications to the docker-compose.yaml are done automatically so you can boot up the software directly.

To learn more, head over to the template repository and follow the instructions there.

Option 2: Only create a customized Docker image¶

If you already have an existing NOMAD Oasis setup, or do not wish to use the template, you can also just create a new Docker image which has your plugin installed as a pip package. For this approach, you need to create a new Dockerfile, which runs the installation step on top of our default image. The basic idea is that your Dockerfile looks something like this:

FROM gitlab-registry.mpcdf.mpg.de/nomad-lab/nomad-fair:latest

# Switch to root user to install packages to the system with pip
USER root

# Install your plugin here, e.g.:
RUN pip install git+https://<repository_url>

# Remember to switch back to the 'nomad' user
USER nomad

Depending on how your plugin code is distributed, you have several options for the actual install steps:

Plugin published in PyPI:
```
RUN pip install <package_name>
```

Plugin code available in GitHub:

RUN pip install git+https://<repository_url>

Plugin published in MPCDF GitLab registry:

RUN pip install nomad-example-schema-plugin --index-url https://gitlab.mpcdf.mpg.de/api/v4/projects/2187/packages/pypi/simple

Copy plugin folder from host machine. Note that the folder needs to be in the Docker build context:

COPY <nomad-plugin-folder-name> <nomad-plugin-folder-name>
RUN cd <nomad-plugin-folder-name> && pip install .

The customized image can then be built like this:

docker build -t nomad-with-plugins .

This will create a new image with the tag nomad-with-plugins, which you can use in your docker-compose.yaml file:

#image: gitlab-registry.mpcdf.mpg.de/nomad-lab/nomad-fair:latest
image: nomad-with-plugins

Option 3 (deprecated): Mount the plugin code directly into the container¶

Attention

This option only works with the old plugin mechanism that is based on nomad_plugin.yaml files instead of Python entry points.

The NOMAD docker image adds the folder /app/plugins to the PYTHONPATH. This means that you can mount your code into the /app/plugins directory via the volumes section of the app and worker services in your docker-compose.yaml.

For example, you can do this by adding an extension to the docker-compose.yaml, e.g. a file called docker-compose.plugins.yaml. Assuming you have cloned three plugins into the Oasis folder as ./nomad-schema-plugin-example, ./nomad-parser-plugin-example and ./nomad-normalizer-plugin-example, your docker-compose.plugins.yaml should look like this:

services:
  worker:
    volumes:
      - ./nomad-schema-plugin-example/nomadschemaexample:/app/plugins/nomadschemaexample
      - ./nomad-parser-plugin-example/nomadparserexample:/app/plugins/nomadparserexample
      - ./nomad-normalizer-plugin-example/nomadparserexample:/app/plugins/nomadparserexample
  app:
    volumes:
      - ./nomad-schema-plugin-example/nomadschemaexample:/app/plugins/nomadschemaexample
      - ./nomad-parser-plugin-example/nomadparserexample:/app/plugins/nomadparserexample
      - ./nomad-normalizer-plugin-example/nomadparserexample:/app/plugins/nomadparserexample

You have to tell docker that there are now two compose files. This can be done via the COMPOSE_FILE environment variable. This is how you can start the Oasis with the plugins:

export COMPOSE_FILE=docker-compose.yaml:docker-compose.plugins.yaml
docker compose up -d

Read the Oasis install guide for more details.