✨ Provide a way to preview locally running applications on Analytical Platform

[jacobwoffenden]

Describe the feature request.

When developing applications on Analytical Platform's cloud development environment, it is essential that users can run and test their applications locally.

Describe the context.

Running Dash apps locally.

Reference: https://user-guidance.analytical-platform.service.justice.gov.uk/appendix/dash.html

Value / Purpose

This functionality exists in JupyterLab's NGINX proxy, but it uses path based routing.

User Types

Analytical Platform users

[Ed-Bajo]

The feature request would be tackled in #4167