Batch Connect - OSC Code Server

Overview

An Open OnDemand Batch Connect app that launches Code Server as an interactive web-based session on OSC HPC clusters. Code Server provides a full VS Code editing experience running on a compute node and accessible through a browser.

This app uses the Batch Connect basic template with Slurm and supports clusters: Ascend and Pitzer.

• Upstream project: Code Server / VS Code
• Batch Connect template: basic
• Scheduler: Slurm

Screenshots

Features

• Full VS Code editor experience in the browser via Code Server
• Multi-cluster support (Ascend, Pitzer)
• Working directory selector for the Code Server session
• Dynamic Code Server module selection via auto_modules_app_code_server
• Password-authenticated sessions
• C/C++ extension support with IntelliSense database on local filesystem
• Telemetry disabled by default
• Module-based software loading via Lmod (project/ondemand, app_code_server/)

Requirements

Compute Node Software

This Batch Connect app requires the following software be installed on the compute nodes that the batch job is intended to run on (NOT the OnDemand node):

• Lmod 6.0.1+ or any other module purge and module load <modules> based CLI used to load appropriate environments within the batch job before launching Code Server
• Code Server 2.x+ available from GitHub: https://github.com/coder/code-server/releases

Open OnDemand

• Tested to work with the latest version of Open OnDemand
• Slurm scheduler

App Installation

1. Clone the repository

cd /var/www/ood/apps/sys
git clone https://github.com/OSC/bc_osc_codeserver.git
cd bc_osc_codeserver

# Pin to a release (recommended)
git checkout v0.13.0

No restart is needed -- Batch Connect apps are not Passenger apps and are detected automatically.

2. Deploy Code Server binary

If you are not using the app_code_server/ module, you can deploy the code-server binary manually:

# Replace URL with latest release from code-server
wget https://github.com/coder/code-server/releases/download/<version>/code-server-<version>-linux-amd64.tar.gz
tar -xzf code-server-<version>-linux-amd64.tar.gz

3. Configure for your site

Edit form.yml and update these values for your cluster:

Attribute	OSC Default	Change to
cluster	ascend, pitzer	Your cluster name(s)
auto_modules_app_code_server	(dynamic)	Code Server module name(s) on your system

In script.sh.erb, the app loads modules with:

module load project/ondemand app_code_server/<version>

Ensure equivalent modules are available on your system, or update the script to point to your code-server binary path.

4. Update the app

cd /var/www/ood/apps/sys/bc_osc_codeserver
git fetch
git checkout <tag>

No restart is needed.

Configuration

form.yml attributes

Attribute	Widget	Description	Default
cluster	select	Target cluster ID(s)	ascend, pitzer
bc_num_hours	number	Maximum wall time (hours)	1
working_dir	path_selector	Working directory for the Code Server session	$HOME
auto_modules_app_code_server	select	Code Server module version to load (auto-detected)	(dynamic)

Known Limitations

• In-app installation of extensions does not work
• The authentication provided by code-server is unencrypted

Troubleshooting

Connection timeout

The app may need more time to start. Increase the connection timeout or check that the compute node can open the required port.

Testing

Site	OOD Version	Scheduler	Status
Ohio Supercomputer Center	4.2.2	Slurm	Production

Contributing

1. Fork it ( https://github.com/OSC/bc_osc_codeserver/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

For bugs or feature requests, open an issue.

References

• Code Server -- the application launched by this app
• VS Code -- the editor Code Server is based on
• code-server GitHub releases -- binary releases of Code Server
• Open OnDemand -- the HPC portal framework
• OOD Batch Connect app development docs
• Changelog -- release history for this app

License

• Documentation, website content, and logo is licensed under CC-BY-4.0
• Code is licensed under GPL-3.0 (See LICENSE.xt)

Acknowledgments

This app is built on Open OnDemand, developed and maintained by the Ohio Supercomputer Center (OSC).

Open OnDemand is supported by the National Science Foundation under awards NSF SI2-SSE-1534949 and NSF CSSI-Frameworks-1835725.