feat(appservice): room provisioning via bridge API (M4c, agent-comms#9)

POST /bridge/v1/provision/rooms (inside the authed bridge block): creates
rooms AS the appservice sender (PL 100 override), optional alias/topic/
invite/space. Space-link failures surface partial success (room_id +
space_linked:false + space_error) instead of orphaning the room behind an
exception (review blocker); invite list capped at 50 (review blocker:
amplification via stolen bridge token); alias length capped. 13+14 vitest.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/appservice/src/__tests__/server.test.ts

@@ -137,6 +137,97 @@ describe('AppserviceDaemon routing', () => {
     expect(res.status).toBe(405);
   });
 
+  it('provisions a room as the AS sender with space linking', async () => {
+    const calls: Array<{ url: URL; body: unknown }> = [];
+    const fetchMock = vi.fn(async (input: URL | string, init?: RequestInit) => {
+      const url = new URL(String(input));
+      calls.push({ url, body: init?.body ? JSON.parse(String(init.body)) : undefined });
+      if (url.pathname.endsWith('/createRoom'))
+        return jsonResponse(200, { room_id: '!new:hs.example' });
+      return jsonResponse(200, {});
+    });
+    const daemon = new AppserviceDaemon(cfg, fetchMock as unknown as typeof fetch, () => {});
+    const res = await daemon.handle(
+      request({
+        method: 'POST',
+        path: '/bridge/v1/provision/rooms',
+        authorizationHeader: 'Bearer bridge-secret',
+        body: {
+          name: 'proj-x',
+          alias: 'mosaic-proj-x',
+          invite: ['@jason.woltje:hs.example'],
+          space_id: '!space:hs.example',
+        },
+      }),
+    );
+    expect(res.status).toBe(200);
+    expect(res.body.room_id).toBe('!new:hs.example');
+    expect(res.body.space_linked).toBe(true);
+    const create = calls.find((c) => c.url.pathname.endsWith('/createRoom'));
+    expect(create!.url.searchParams.get('user_id')).toBe('@mosaic-as:hs.example');
+    const body = create!.body as Record<string, unknown>;
+    expect(body.room_alias_name).toBe('mosaic-proj-x');
+    expect((body.power_level_content_override as Record<string, unknown>).users).toEqual({
+      '@mosaic-as:hs.example': 100,
+    });
+    expect(calls.some((c) => c.url.pathname.includes('/state/m.space.child/'))).toBe(true);
+    expect(calls.some((c) => c.url.pathname.includes('/state/m.space.parent/'))).toBe(true);
+  });
+
+  it('space-link failure still returns the room id (no orphan)', async () => {
+    const fetchMock = vi.fn(async (input: URL | string) => {
+      const url = new URL(String(input));
+      if (url.pathname.endsWith('/createRoom'))
+        return jsonResponse(200, { room_id: '!new:hs.example' });
+      if (url.pathname.includes('/state/m.space.child/'))
+        return jsonResponse(403, { errcode: 'M_FORBIDDEN', error: 'no PL in space' });
+      return jsonResponse(200, {});
+    });
+    const daemon = new AppserviceDaemon(cfg, fetchMock as unknown as typeof fetch, () => {});
+    const res = await daemon.handle(
+      request({
+        method: 'POST',
+        path: '/bridge/v1/provision/rooms',
+        authorizationHeader: 'Bearer bridge-secret',
+        body: { name: 'proj-x', space_id: '!space:hs.example' },
+      }),
+    );
+    expect(res.status).toBe(200);
+    expect(res.body.room_id).toBe('!new:hs.example');
+    expect(res.body.space_linked).toBe(false);
+    expect(String(res.body.space_error)).toContain('403');
+  });
+
+  it('invite list cap enforced', async () => {
+    const { daemon } = makeDaemon();
+    const res = await daemon.handle(
+      request({
+        method: 'POST',
+        path: '/bridge/v1/provision/rooms',
+        authorizationHeader: 'Bearer bridge-secret',
+        body: { name: 'x', invite: Array.from({ length: 51 }, (_, i) => `@u${i}:hs`) },
+      }),
+    );
+    expect(res.status).toBe(400);
+  });
+
+  it('provision rejects bad payloads and requires auth', async () => {
+    const { daemon } = makeDaemon();
+    const noAuth = await daemon.handle(
+      request({ method: 'POST', path: '/bridge/v1/provision/rooms', body: { name: 'x' } }),
+    );
+    expect(noAuth.status).toBe(403);
+    const bad = await daemon.handle(
+      request({
+        method: 'POST',
+        path: '/bridge/v1/provision/rooms',
+        authorizationHeader: 'Bearer bridge-secret',
+        body: { name: '', alias: 'BAD ALIAS' },
+      }),
+    );
+    expect(bad.status).toBe(400);
+  });
+
   it('empty bridge token list denies everything', async () => {
     const daemon = new AppserviceDaemon({ ...cfg, bridgeTokens: [] }, undefined, () => {});
     const res = await daemon.handle(

apps/appservice/src/server.ts

@@ -5,6 +5,7 @@ import {
   TransactionHandler,
   validateBridgeMessage,
   validateBridgeTyping,
+  validateProvisionRoom,
 } from '@mosaicstack/appservice';
 import type { AppserviceConfig, MatrixEvent } from '@mosaicstack/appservice';
 
@@ -109,6 +110,27 @@ export class AppserviceDaemon {
           await this.intent.setTyping(req.body.room_id, req.body.agent, req.body.typing);
           return { status: 200, body: {} };
         }
+        if (req.method === 'POST' && req.path === '/bridge/v1/provision/rooms') {
+          validateProvisionRoom(req.body);
+          const result = await this.intent.createRoom({
+            name: req.body.name,
+            alias: req.body.alias,
+            topic: req.body.topic,
+            invite: req.body.invite,
+            spaceId: req.body.space_id,
+          });
+          this.log(
+            `provisioned room ${result.roomId} (${req.body.name}) space_linked=${result.spaceLinked}`,
+          );
+          return {
+            status: 200,
+            body: {
+              room_id: result.roomId,
+              space_linked: result.spaceLinked,
+              ...(result.spaceError ? { space_error: result.spaceError } : {}),
+            },
+          };
+        }
       } catch (error) {
         const message = error instanceof Error ? error.message : String(error);
         this.log(`bridge error ${req.method} ${req.path}: ${message}`);