0008. Router type (HashRouter / BrowserRouter) chosen by configuration

• Status: Accepted (retroactive)
• Date: 2021-11-08

Context and Problem Statement

The demo is deployed both to GitHub Pages (static hosting, no rewrite of deep links to index.html, sub-path /Front/) and to servers/containers that can rewrite all paths to the SPA.

Considered Options

• BrowserRouter only - breaks deep links on GitHub Pages.
• HashRouter only - ugly URLs, breaks OAuth return URLs.
• Choose per deployment (chosen).

Decision Outcome

REACT_APP_ROUTING_TYPE (now VITE_APP_ROUTING_TYPE, or window.VITE_APP_ROUTING_TYPE at runtime, see 0009) selects HashRouter or BrowserRouter in components/Routes/index.tsx via utils/router.ts. GitHub Pages builds set HashRouter; the Docker image defaults to ROUTING_TYPE=HashRouter. Code that builds URLs (social login return URLs in SocialButtons.tsx) adds /# or %23 when hash routing is active. Apache mod_rewrite was enabled later for BrowserRouter deployments.

Consequences

• Good: one build works on static hosting and on real servers.
• Bad: every absolute URL handed to the API (OAuth, payment return, e-mail links) must be router-aware; several later bug fixes concern return URLs.

Evidence

• 8dc08824 2021-11-08 “env for build and test (#110)” - front/.env, front/.github/workflows/pages.yml, front/src/components/Routes/{BrowserRouter,HashRouter,index}.tsx
• 5ece05f9 2022-01-26 “return url fix (#156)”
• 79b88b78 2022-02-09 “google login and mattermost fix refresh data (#167)”
• d4f4a06f 2024-11-20 “rewrite all (#511)” - front/Dockerfile (a2enmod rewrite)
• 32003f17 2024-11-27 “Feature/mod rewrite (#515)” - front/config/php/index.php, front/index.html
• current: front/src/utils/router.ts, front/Dockerfile (ENV ROUTING_TYPE="HashRouter")