Setting up a development install

System requirements

JupyterHub can only run on macOS or Linux operating systems. If you are using Windows, we recommend using VirtualBox or a similar system to run Ubuntu Linux for development.

Install Python

JupyterHub is written in the Python programming language and requires you have at least version 3.6 installed locally. If you haven’t installed Python before, the recommended way to install it is to use Miniforge.

Install nodejs

NodeJS 12+ is required for building some JavaScript components. configurable-http-proxy, the default proxy implementation for JupyterHub, is written in Javascript. If you have not installed NodeJS before, we recommend installing it in the miniconda environment you set up for Python. You can do so with conda install nodejs.

Many in the Jupyter community use [nvm](nvm-sh/nvm) to managing node dependencies.

Install git

JupyterHub uses Git & GitHub for development & collaboration. You need to install git to work on JupyterHub. We also recommend getting a free account on GitHub.com.

Setting up a development install

When developing JupyterHub, you would need to make changes and be able to instantly view the results of the changes. To achieve that, a developer install is required.

Note

This guide does not attempt to dictate how development environments should be isolated since that is a personal preference and can be achieved in many ways, for example, tox, conda, docker, etc. See this forum thread for a more detailed discussion.

1. Clone the JupyterHub git repository to your computer.

   git clone https://github.com/jupyterhub/jupyterhub
   cd jupyterhub
   

2. Make sure the python you installed and the npm you installed are available to you on the command line.

   python -V
   

   This should return a version number greater than or equal to 3.6.

   npm -v
   

   This should return a version number greater than or equal to 5.0.

3. Install configurable-http-proxy (required to run and test the default JupyterHub configuration) and yarn (required to build some components):

   npm install -g configurable-http-proxy yarn
   

   If you get an error that says Error: EACCES: permission denied, you might need to prefix the command with sudo. sudo may be required to perform a system-wide install. If you do not have access to sudo, you may instead run the following commands:

   npm install configurable-http-proxy yarn
   export PATH=$PATH:$(pwd)/node_modules/.bin
   

   The second line needs to be run every time you open a new terminal.

   If you are using conda you can instead run:

   conda install configurable-http-proxy yarn
   

4. Install an editable version of JupyterHub and its requirements for development and testing. This lets you edit JupyterHub code in a text editor & restart the JupyterHub process to see your code changes immediately.

   python3 -m pip install --editable ".[test]"
   

5. Set up a database.

   The default database engine is sqlite so if you are just trying to get up and running quickly for local development that should be available via Python. See The Hub’s Database for details on other supported databases.

6. You are now ready to start JupyterHub!

   jupyterhub
   

7. You can access JupyterHub from your browser at http://localhost:8000 now.

Happy developing!

Using DummyAuthenticator & SimpleLocalProcessSpawner

To simplify testing of JupyterHub, it is helpful to use DummyAuthenticator instead of the default JupyterHub authenticator and SimpleLocalProcessSpawner instead of the default spawner.

There is a sample configuration file that does this in testing/jupyterhub_config.py. To launch JupyterHub with this configuration:

jupyterhub -f testing/jupyterhub_config.py

The default JupyterHub authenticator & spawner require your system to have user accounts for each user you want to log in to JupyterHub as.

DummyAuthenticator allows you to log in with any username & password, while SimpleLocalProcessSpawner allows you to start servers without having to create a Unix user for each JupyterHub user. Together, these make it much easier to test JupyterHub.

Tip: If you are working on parts of JupyterHub that are common to all authenticators & spawners, we recommend using both DummyAuthenticator & SimpleLocalProcessSpawner. If you are working on just authenticator-related parts, use only SimpleLocalProcessSpawner. Similarly, if you are working on just spawner-related parts, use only DummyAuthenticator.

Troubleshooting

This section lists common ways setting up your development environment may fail, and how to fix them. Please add to the list if you encounter yet another way it can fail!

lessc not found

If the python3 -m pip install --editable . command fails and complains about lessc being unavailable, you may need to explicitly install some additional JavaScript dependencies:

npm install

This will fetch client-side JavaScript dependencies necessary to compile CSS.

You may also need to manually update JavaScript and CSS after some development updates, with:

python3 setup.py js    # fetch updated client-side js
python3 setup.py css   # recompile CSS from LESS sources
python3 setup.py jsx   # build React admin app