ckbhatt / dockerspawner

Spawns JupyterHub single user servers in Docker containers

Prerequisites | Installation | Configuration | Building the Docker images | Contributing | License | Getting help

DockerSpawner

DockerSpawner enables JupyterHub to spawn single user notebook servers in Docker containers.

Prerequisites

JupyterHub 0.7 or above is required, which also means Python 3.3 or above.

Installation

Install dockerspawner to the system:

pip install dockerspawner

Configuration

Choose a spawner

Two basic types of spawners are available for dockerspawner:

• DockerSpawner: useful if you would like to spawn single user notebook servers on the fly. It will take an authenticated user and spawn a notebook server in a Docker container for the user.

• SystemUserSpawner: useful if you would like to spawn single user notebook servers that correspond to the system's users.

In most cases, we recommend using DockerSpawner. Use cases where you may wish to use SystemUserSpawner are:

• You are using docker just for environment management, but are running on a system where the users already have accounts and files they should be able to access from within the container. For example, you wish to use the system users and user home directories that already exist on a system.
• You are using an external service, such as nbgrader, that relies on distinct unix user ownership and permissions.

If neither of those cases applies, DockerSpawner is probably the right choice.

DockerSpawner

Tell JupyterHub to use DockerSpawner by adding the following line to your jupyterhub_config.py:

    c.JupyterHub.spawner_class = 'dockerspawner.DockerSpawner'

There is a complete example in examples/oauth for using GitHub OAuth to authenticate users, and spawn containers with docker.

SystemUserSpawner

If you want to spawn notebook servers for users that correspond to system users, you can use the SystemUserSpawner instead. Add the following to your jupyterhub_config.py:

    c.JupyterHub.spawner_class = 'dockerspawner.SystemUserSpawner'

The SystemUserSpawner will also need to know where the user home directories are on the host. By default, it expects them to be in /home/<username>, but if you want to change this, you'll need to further modify the jupyterhub_config.py. For example, the following will look for a user's home directory on the host system at /volumes/user/<username>:

    c.SystemUserSpawner.host_homedir_format_string = '/volumes/user/{username}'

For a full example of how SystemUserSpawner is used, see the compmodels-jupyterhub repository (this additionally runs the JupyterHub server within a docker container, and authenticates users using GitHub OAuth).

Using Docker Swarm (not swarm mode!)

Note: This is the older Docker Swarm, which makes a swarm look like a single docker instance. For the newer Docker Swarm Mode, see SwarmSpawner.

Both DockerSpawner and SystemUserSpawner are compatible with Docker Swarm when multiple system nodes will be used in a cluster for JupyterHub. Simply add 0.0.0.0 to your jupyterhub_config.py file as the host_ip:

c.DockerSpawner.host_ip = "0.0.0.0"

This will configure DockerSpawner and SystemUserSpawner to get the container IP address and port number using the docker port command.

Data persistence and DockerSpawner

With DockerSpawner, the user's home directory is not persistent by default, so some configuration is required to do so unless the directory is to be used with temporary or demonstration JupyterHub deployments.

The simplest version of persistence to the host filesystem is to isolate users in the filesystem, but leave everything owned by the same 'actual' user with DockerSpawner. That is, using docker mounts to isolate user files, not ownership or permissions on the host.

Volume mapping for DockerSpawner in jupyterhub_config.py is required configuration for persistence. To map volumes from the host file/directory to the container (referred to as guest) file/directory mount point, set the c.DockerSpawner.volumes to specify the guest mount point (bind) for the volume.

If you use {username} in either the host or guest file/directory path, username substitution will be done and {username} will be replaced with the current user's name.

(Note: The jupyter/docker-stacks notebook images run the Notebook server as user jovyan and set the user's notebook directory to /home/jovyan/work.)

# Explicitly set notebook directory because we'll be mounting a host volume to
# it.  Most jupyter/docker-stacks *-notebook images run the Notebook server as
# user `jovyan`, and set the notebook directory to `/home/jovyan/work`.
# We follow the same convention.
notebook_dir = os.environ.get('DOCKER_NOTEBOOK_DIR') or '/home/jovyan/work'
c.DockerSpawner.notebook_dir = notebook_dir

# Mount the real user's Docker volume on the host to the notebook user's
# notebook directory in the container
c.DockerSpawner.volumes = { 'jupyterhub-user-{username}': notebook_dir }

The jupyterhub-deploy-docker repo contains a reference deployment that persists the notebook directory; see its jupyterhub_config.py for an example configuration.

See Docker documentation on data volumes for more information on data persistence.

Memory limits

If you have jupyterhub >= 0.7, you can set a memory limit for each user's container easily.

c.Spawner.mem_limit = '2G'

The value can either be an integer (bytes) or a string with a 'K', 'M', 'G' or 'T' prefix.

Picking or building a Docker image

By default, DockerSpawner uses the jupyterhub/singleuser image with the appropriate tag that pins the right version of JupyterHub. Any of the existing Jupyter docker stacks can be used with JupyterHub, provided that the version of JupyterHub in the image matches, and are encouraged as the image of choice. Make sure to pick a tag!

c.DockerSpawner.image = 'jupyter/scipy-notebook:8f56e3c47fec'

The docker-stacks are moving targets with always changing versions. Since you need to make sure that JupyterHub in the image is compatible with JupyterHub, always include the :hash tag part when specifying the image.

You can also build your own image. The only requirements for an image to be used with JupyterHub:

1. it has Python >= 3.4
2. it has JupyterHub
3. it has the Jupyter notebook package
4. CMD launches jupyterhub-singleuser OR the c.Spawner.cmd configuration is used to do this.

For just about any starting image, you can make it work with JupyterHub by installing the appropriate JupyterHub version and the Jupyter notebook package.

For instance, from the docker-stacks, pin your JupyterHub version and you are done:

FROM jupyter/scipy-notebook:8f56e3c47fec
ARG JUPYTERHUB_VERSION=0.8.0
RUN pip3 install --no-cache \
    jupyterhub==$JUPYTERHUB_VERSION

Or for the absolute minimal JupyterHub user image starting only from the base Python image:

FROM python:3.6
RUN pip3 install \
    jupyterhub==0.7.2 \
    'notebook>=5.0,<=6.0'

# create a user, since we don't want to run as root
RUN useradd -m jovyan
ENV HOME=/home/jovyan
WORKDIR $HOME
USER jovyan

CMD ["jupyterhub-singleuser"]

This Dockerfile should work with just about any base image in the FROM line, provided it has Python 3 installed.

Contributing

If you would like to contribute to the project, please read our contributor documentation and the CONTRIBUTING.md.

For a development install, clone the repository and then install from source:

git clone https://github.com/jupyterhub/dockerspaawner
cd dockerspawner
pip3 install -r dev-requirements.txt -e .

License

We use a shared copyright model that enables all contributors to maintain the copyright on their contributions.

All code is licensed under the terms of the revised BSD license.

Getting help

We encourage you to ask questions on the mailing list, and you may participate in development discussions or get live help on Gitter.

Resources

Dockerspawner and JupyterHub

• Reporting Issues
• JupyterHub tutorial | Repo | Tutorial documentation
• Documentation for JupyterHub | PDF (latest) | PDF (stable)
• Documentation for JupyterHub's REST API

Project Jupyter

• Documentation for Project Jupyter | PDF
• Project Jupyter website