feat: add space subdomain routing and ownership support

- Traefik wildcard HostRegexp for <space>.r*.online subdomains
- Middleware subdomain extraction and path rewriting
- Provision endpoint with owner_did acknowledgement
- Registry enforces space ownership via EncryptID JWT

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -23,7 +23,7 @@ services:
       - /tmp
     labels:
       - "traefik.enable=true"
-      - "traefik.http.routers.rcal.rule=Host(`rcal.jeffemmett.com`) || Host(`rcal.online`) || Host(`www.rcal.online`) || Host(`booking.xhiva.art`)"
+      - "traefik.http.routers.rcal.rule=Host(`rcal.jeffemmett.com`) || Host(`rcal.online`) || Host(`www.rcal.online`) || Host(`booking.xhiva.art`) || HostRegexp(`{subdomain:[a-z0-9-]+}.rcal.online`)"
       - "traefik.http.routers.rcal.entrypoints=web"
       - "traefik.http.services.rcal.loadbalancer.server.port=3000"
     networks:

src/app/api/internal/provision/route.ts

@@ -4,6 +4,9 @@ import { NextResponse } from "next/server";
  * Internal provision endpoint — called by rSpace Registry when activating
  * this app for a space. No auth required (only reachable from Docker network).
  *
+ * Payload: { space, description, admin_email, public, owner_did }
+ * The owner_did identifies who registered the space via the registry.
+ *
  * rcal will associate calendars with space slugs in future.
  * Acknowledges provisioning for now.
  */
@@ -13,5 +16,6 @@ export async function POST(request: Request) {
   if (!space) {
     return NextResponse.json({ error: "Missing space name" }, { status: 400 });
   }
-  return NextResponse.json({ status: "ok", space, message: "rcal space acknowledged" });
+  const ownerDid: string = body.owner_did || "";
+  return NextResponse.json({ status: "ok", space, owner_did: ownerDid, message: "rcal space acknowledged" });
 }

src/middleware.ts

@@ -0,0 +1,45 @@
+import { NextResponse } from 'next/server';
+import type { NextRequest } from 'next/server';
+
+/**
+ * Middleware to handle subdomain-based space routing.
+ *
+ * Routes:
+ * - rcal.online -> home/landing page
+ * - www.rcal.online -> home/landing page
+ * - <space>.rcal.online -> rewrite to /s/<space>
+ *
+ * Also handles localhost for development.
+ */
+export function middleware(request: NextRequest) {
+  const url = request.nextUrl.clone();
+  const hostname = request.headers.get('host') || '';
+
+  let subdomain: string | null = null;
+
+  // Match production: <space>.rcal.online
+  const match = hostname.match(/^([a-z0-9][a-z0-9-]*[a-z0-9]|[a-z0-9])\.\w+\.online/);
+  if (match && match[1] !== 'www') {
+    subdomain = match[1];
+  } else if (hostname.includes('localhost')) {
+    // Development: <space>.localhost:port
+    const parts = hostname.split('.localhost')[0].split('.');
+    if (parts.length > 0 && parts[0] !== 'localhost') {
+      subdomain = parts[parts.length - 1];
+    }
+  }
+
+  // If we have a subdomain, rewrite root path to space page
+  if (subdomain && subdomain.length > 0 && url.pathname === '/') {
+    url.pathname = `/s/${subdomain}`;
+    return NextResponse.rewrite(url);
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: [
+    '/((?!_next/static|_next/image|favicon.ico|.*\\..*|api).*)',
+  ],
+};