Web R/DataSHIELD (webds)

R in the browser with webR: console, editor tabs, file browser, plot and help viewers. DataSHIELD client packages (DSI, DSOpal) can be installed and connect to public Opal servers.

Live: https://www.obiba.org/webDS/

Deployment notes

• Cross-origin isolation: webR needs SharedArrayBuffer for interrupt (Ctrl+C) and readline(), so pages must be served with Cross-Origin-Opener-Policy: same-origin and Cross-Origin-Embedder-Policy: require-corp. The dev server sends them (quasar.config.ts). On static hosts that cannot (GitHub Pages), public/coi-serviceworker.js adds them; the page reloads once on first visit.
• GitHub Pages: .github/workflows/pages.yml builds and deploys on push to master. PUBLIC_PATH sets the base path (/<repo>/).
• webR assets and packages are loaded from the webR CDN (webr.r-wasm.org, repo.r-wasm.org).
• HTTP from R (curl/httr, used by opalr): webR tunnels TCP through a WebSocket relay run by r-universe (ws.r-universe.dev). TLS is end to end, but only servers reachable from the internet work. httr's connect timeout is raised to 60s (src/stores/init.R); the relay appears to cap connections at about 30s.
• Fetch transport (prototype, ~10x faster): options(webds.fetch = "<opal host>") sends httr requests to that host from the browser instead of through the relay. The Opal server must support the X-Opal-Session header and allow CORS from the page origin (opal branch feat/session-header); dev/opal-cors-proxy.py simulates that in front of an unpatched Opal.
• Files live in the in-memory webR file system and are lost on reload: download what you want to keep.

Development

Install the dependencies

npm install

Start the app in development mode (HMR, error reporting, etc.)

npm run dev

Build the app for production

npm run build