fix(M2-005,M2-006): enforce user ownership at repo level for conversations and agents (#293)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/gateway/src/__tests__/resource-ownership.test.ts

@@ -57,11 +57,13 @@ function createBrain() {
 describe('Resource ownership checks', () => {
   it('forbids access to another user conversation', async () => {
     const brain = createBrain();
-    brain.conversations.findById.mockResolvedValue({ id: 'conv-1', userId: 'user-2' });
+    // The repo enforces ownership via the WHERE clause; it returns undefined when the
+    // conversation does not belong to the requesting user.
+    brain.conversations.findById.mockResolvedValue(undefined);
     const controller = new ConversationsController(brain as never);
 
     await expect(controller.findOne('conv-1', { id: 'user-1' })).rejects.toBeInstanceOf(
-      ForbiddenException,
+      NotFoundException,
     );
   });
 

apps/gateway/src/agent/agent-configs.controller.ts

@@ -62,7 +62,11 @@ export class AgentConfigsController {
     if (!agent.isSystem && agent.ownerId !== user.id) {
       throw new ForbiddenException('Agent does not belong to the current user');
     }
-    const updated = await this.brain.agents.update(id, dto);
+
+    // Pass ownerId for user agents so the repo WHERE clause enforces ownership.
+    // For system agents (admin path) pass undefined so the WHERE matches only on id.
+    const ownerId = agent.isSystem ? undefined : user.id;
+    const updated = await this.brain.agents.update(id, dto, ownerId);
     if (!updated) throw new NotFoundException('Agent not found');
     return updated;
   }
@@ -78,7 +82,8 @@ export class AgentConfigsController {
     if (agent.ownerId !== user.id) {
       throw new ForbiddenException('Agent does not belong to the current user');
     }
-    const deleted = await this.brain.agents.remove(id);
+    // Pass ownerId so the repo WHERE clause enforces ownership at the DB level.
+    const deleted = await this.brain.agents.remove(id, user.id);
     if (!deleted) throw new NotFoundException('Agent not found');
   }
 }

apps/gateway/src/conversations/conversations.controller.ts

@@ -2,6 +2,7 @@ import {
   Body,
   Controller,
   Delete,
+  ForbiddenException,
   Get,
   HttpCode,
   HttpStatus,
@@ -16,7 +17,6 @@ import type { Brain } from '@mosaic/brain';
 import { BRAIN } from '../brain/brain.tokens.js';
 import { AuthGuard } from '../auth/auth.guard.js';
 import { CurrentUser } from '../auth/current-user.decorator.js';
-import { assertOwner } from '../auth/resource-ownership.js';
 import {
   CreateConversationDto,
   UpdateConversationDto,
@@ -35,7 +35,9 @@ export class ConversationsController {
 
   @Get(':id')
   async findOne(@Param('id') id: string, @CurrentUser() user: { id: string }) {
-    return this.getOwnedConversation(id, user.id);
+    const conversation = await this.brain.conversations.findById(id, user.id);
+    if (!conversation) throw new NotFoundException('Conversation not found');
+    return conversation;
   }
 
   @Post()
@@ -53,8 +55,7 @@ export class ConversationsController {
     @Body() dto: UpdateConversationDto,
     @CurrentUser() user: { id: string },
   ) {
-    await this.getOwnedConversation(id, user.id);
-    const conversation = await this.brain.conversations.update(id, dto);
+    const conversation = await this.brain.conversations.update(id, user.id, dto);
     if (!conversation) throw new NotFoundException('Conversation not found');
     return conversation;
   }
@@ -62,15 +63,16 @@ export class ConversationsController {
   @Delete(':id')
   @HttpCode(HttpStatus.NO_CONTENT)
   async remove(@Param('id') id: string, @CurrentUser() user: { id: string }) {
-    await this.getOwnedConversation(id, user.id);
-    const deleted = await this.brain.conversations.remove(id);
+    const deleted = await this.brain.conversations.remove(id, user.id);
     if (!deleted) throw new NotFoundException('Conversation not found');
   }
 
   @Get(':id/messages')
   async listMessages(@Param('id') id: string, @CurrentUser() user: { id: string }) {
-    await this.getOwnedConversation(id, user.id);
-    return this.brain.conversations.findMessages(id);
+    // Verify ownership explicitly to return a clear 404 rather than an empty list.
+    const conversation = await this.brain.conversations.findById(id, user.id);
+    if (!conversation) throw new NotFoundException('Conversation not found');
+    return this.brain.conversations.findMessages(id, user.id);
   }
 
   @Post(':id/messages')
@@ -79,19 +81,16 @@ export class ConversationsController {
     @Body() dto: SendMessageDto,
     @CurrentUser() user: { id: string },
   ) {
-    await this.getOwnedConversation(id, user.id);
-    return this.brain.conversations.addMessage({
-      conversationId: id,
-      role: dto.role,
-      content: dto.content,
-      metadata: dto.metadata,
-    });
-  }
-
-  private async getOwnedConversation(id: string, userId: string) {
-    const conversation = await this.brain.conversations.findById(id);
-    if (!conversation) throw new NotFoundException('Conversation not found');
-    assertOwner(conversation.userId, userId, 'Conversation');
-    return conversation;
+    const message = await this.brain.conversations.addMessage(
+      {
+        conversationId: id,
+        role: dto.role,
+        content: dto.content,
+        metadata: dto.metadata,
+      },
+      user.id,
+    );
+    if (!message) throw new ForbiddenException('Conversation not found or access denied');
+    return message;
   }
 }