Files
supabase/apps/www/content/md/realtime.md
Pamela Chia d409836ca7 feat(www,docs): serve marketing pages as .md, advertise via link rel=alternate (#45277)
## Summary

Adds `/<page>.md` routes for 10 marketing/product pages (homepage, auth,
database, edge-functions, realtime, storage, vector, pricing,
modules/cron, modules/queues) so AI agents can fetch clean markdown
instead of parsing JS-rendered HTML. Also advertises the markdown
alternate via `<link rel="alternate" type="text/markdown">` on marketing
and docs pages so agents can discover it.

Pricing is generated dynamically via `generatePricingContent()` (single
source of truth with `/llms.txt` and `/llms-full.txt`); the other nine
slugs are bundled at build time from `content/md/*.md` into a
`MD_CONTENT` map.

Supersedes #44891 (rebased fresh off current master to avoid a 9-commit
replay over rename/rename conflicts created by #44897).

## Changes

- New `/api-v2/md/[...slug]` route handler returns the bundled markdown
(or dynamic pricing) with `Content-Type: text/markdown`,
`X-Content-Type-Options: nosniff`, and appropriate cache headers
- Middleware rewrites `/<slug>.md` and `Accept: text/markdown` to the
API route for the `MD_PAGES` allowlist; trailing-slash variants
(`/auth/`) are normalized so they resolve the same as `/auth`
- Build-time codegen `scripts/generateMdContent.mjs` scans `content/md/`
and emits `app/api-v2/md/content.generated.ts` exporting both
`MD_CONTENT` (Map) and `MD_PAGES` (Set, incl. dynamic `pricing`). Fails
the build on slug collision between `content/md/` and `DYNAMIC_SLUGS`.
Adding a new marketing `.md` is just dropping a file in `content/md/`
(also update `PRODUCT_OVERVIEW_LINKS` in `/llms.txt` since that list is
editorial).
- 8 permanent redirects `/llms/<product>.txt` → `/<product>.md` so
legacy URLs in caches and downstream `llms.txt` copies keep working
- `/llms.txt` product overview now references `.md` URLs (incl.
`modules/cron`, `modules/queues`); `/llms-full.txt` iterates
`MD_CONTENT.values()` (homepage first, then alphabetical) and appends
dynamic pricing
- `/llms/[slug]` route slimmed to proxy SDK reference files (`js.txt`,
`dart.txt`, etc.) since redirects handle product slugs and pricing;
pricing branch retained as fallback in case redirects are bypassed
- `apps/www/pages/_app.tsx` injects the alternate link conditionally
based on `MD_PAGES`; `/pricing` (app router) sets it via page metadata
- `apps/docs/app/page.tsx` (the `/docs` root) sets the text/markdown
alternate to `/llms-full.txt`; per-guide pages override with their
specific `.md` URL via `genGuideMeta` in `GuidesMdx.utils.tsx`. Other
docs pages (reference, troubleshooting) inherit nothing.
- `apps/www/.vercelignore`: replaces the prior `*.md`/`README.md` rules
with `*.md` + `!content/md/**/*.md` so Edge Function READMEs and future
scratch `.md` files aren't silently shipped to the build artifact
- Drops `apps/www/data/llms/*.txt` and the related
`outputFileTracingIncludes`
- Test coverage for the new middleware branches: `.md` suffix rewrite
(allowlisted vs. fall-through), `Accept: text/markdown` content
negotiation, trailing-slash normalization

## Testing (Vercel preview)

Local dev server smoke tests passing on `:3771` after each iteration.
Re-verified on the preview URL after the latest hardening commit:

- [x] `curl -I https://<preview>/llms/auth.txt` — expect `308 Permanent
Redirect` to `/auth.md`
- [x] `curl https://<preview>/auth.md | head -3` — expect `# Supabase
Auth`
- [x] `curl https://<preview>/pricing.md | head -3` — expect `# Supabase
Pricing` with current tier values
- [x] `curl https://<preview>/modules/cron.md | head -3` — expect `#
Supabase Cron`
- [x] `curl -H 'Accept: text/markdown' https://<preview>/ | head -3` —
expect `# Supabase` (homepage.md)
- [x] `curl https://<preview>/llms.txt` — Product Overview section lists
`.md` URLs and includes Cron + Queues
- [x] `curl https://<preview>/llms-full.txt | grep -E '^# Supabase
(Cron\|Queues\|Pricing)'` — Cron and Pricing each match once; Queues
matches twice (marketing module + existing docs guide)
- [x] View source on `/`, `/pricing`, `/database` — expect `<link
rel="alternate" type="text/markdown" href="/<slug>.md">`
- [x] View source on `/docs` — expect `<link rel="alternate"
type="text/markdown" href="/llms-full.txt">`
- [x] View source on a docs guide page (e.g., `/docs/guides/auth`) —
expect per-guide `.md` alternate; reference/troubleshooting pages should
NOT emit a markdown alternate
- [x] `curl -I https://<preview>/auth.md` — expect
`X-Content-Type-Options: nosniff`
- [x] `curl -I -L -H 'Accept: text/markdown' https://<preview>/auth/` —
should resolve to markdown content (trailing-slash normalization, with
Vercel's auto-redirect)

## Linear

- fixes GROWTH-760

## Follow-up (separate PR)

GROWTH-760 also asks about extending `.md` to blog/customers/events.
Different mechanism (path-prefix middleware, MDX read at request time
via `gray-matter`) so it deserves its own review. Will open a follow-up
PR after this lands.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Serve prebuilt and dynamic Markdown docs via new markdown endpoints
and routing; pages now advertise markdown alternates (including
pricing).
  * Added Cron and Queues module documentation pages.

* **Documentation**
  * Minor formatting tweaks to Realtime and Storage docs.

* **Chores**
* Added build-time Markdown content generation and adjusted
ignore/deploy rules for generated files.
* Added redirects from legacy text-based product URLs to new markdown
pages.

* **Tests**
* Expanded tests for markdown routing and content-negotiation behavior.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
2026-04-28 16:41:03 +09:00

1.7 KiB

Supabase Realtime

Sync client state globally over WebSockets in real time.

Supabase Realtime enables live data synchronization between your database and connected clients. It provides three capabilities: listening to database changes, tracking user presence, and broadcasting arbitrary messages between clients.

Capabilities

Database Changes

Listen to Postgres INSERT, UPDATE, and DELETE events in real time. Subscribe to specific tables, filter by columns, and receive only the changes you care about. Powered by Postgres logical replication.

Presence

Store and synchronize online user state across all connected clients. Track who is online, what page they are viewing, or their cursor position. State is automatically cleaned up when clients disconnect.

Broadcast

Send arbitrary messages to all clients subscribed to the same Channel. Useful for typing indicators, live cursors, game state, notifications, or any real-time communication that does not need to be persisted.

Technical Details

  • Transport: WebSockets
  • Protocol: Phoenix Channels
  • Database integration: Postgres logical replication (CDC)
  • Client libraries: JavaScript (supabase-js), Dart (Flutter), Swift, Kotlin
  • Authorization: Row Level Security policies applied to database change subscriptions
  • Scaling: horizontally scalable across multiple nodes

Common Use Cases

  • Collaborative editing and live cursors
  • Chat and messaging applications
  • Live dashboards and analytics
  • Multiplayer games
  • Notifications and activity feeds
  • Auction and bidding systems