Fixes #756 (#763)

apps/gateway/src/chat/chat.gateway-redaction.spec.ts

@@ -4,6 +4,10 @@ import { ChatGateway } from './chat.gateway.js';
 const CONVERSATION_ID = 'conversation-1';
 const CANARY = 'sk_canary12345678';
 
+function clientConversationKey(clientId: string, conversationId: string): string {
+  return `${clientId}\u0000${conversationId}`;
+}
+
 type GatewayInternals = {
   clientSessions: Map<string, unknown>;
   relayEvent(client: unknown, conversationId: string, event: unknown): void;
@@ -40,6 +44,7 @@ describe('ChatGateway redaction boundary', (): void => {
       emit: vi.fn(),
     };
     const session = {
+      clientId: client.id,
       conversationId: CONVERSATION_ID,
       cleanup: vi.fn(),
       assistantText: '',
@@ -47,7 +52,7 @@ describe('ChatGateway redaction boundary', (): void => {
       pendingToolCalls: new Map(),
       scope: { userId: 'user-1', tenantId: 'tenant-1' },
     };
-    gateway.clientSessions.set(client.id, session);
+    gateway.clientSessions.set(clientConversationKey(client.id, CONVERSATION_ID), session);
 
     gateway.relayEvent(client, CONVERSATION_ID, {
       type: 'message_update',
@@ -139,6 +144,51 @@ describe('ChatGateway redaction boundary', (): void => {
     });
   });
 
+  it('isolates concurrent conversation streams sharing one Discord socket', (): void => {
+    const { gateway } = buildGateway();
+    const client = {
+      connected: true,
+      id: 'discord-client',
+      data: { user: { id: 'user-1' } },
+      emit: vi.fn(),
+    };
+    const firstConversation = 'Nova:discord:thread-1';
+    const secondConversation = 'Nova:discord:thread-2';
+    const createSession = (conversationId: string) => ({
+      clientId: client.id,
+      conversationId,
+      cleanup: vi.fn(),
+      assistantText: '',
+      toolCalls: [],
+      pendingToolCalls: new Map(),
+      scope: { userId: 'user-1', tenantId: 'tenant-1' },
+    });
+    const firstSession = createSession(firstConversation);
+    const secondSession = createSession(secondConversation);
+    gateway.clientSessions.set(clientConversationKey(client.id, firstConversation), firstSession);
+    gateway.clientSessions.set(clientConversationKey(client.id, secondConversation), secondSession);
+
+    gateway.relayEvent(client, firstConversation, {
+      type: 'message_update',
+      assistantMessageEvent: { type: 'text_delta', delta: 'first response ' },
+    });
+    gateway.relayEvent(client, secondConversation, {
+      type: 'message_update',
+      assistantMessageEvent: { type: 'text_delta', delta: 'second response ' },
+    });
+
+    expect(firstSession.assistantText).toBe('first response ');
+    expect(secondSession.assistantText).toBe('second response ');
+    expect(client.emit).toHaveBeenCalledWith('agent:text', {
+      conversationId: firstConversation,
+      text: 'first response ',
+    });
+    expect(client.emit).toHaveBeenCalledWith('agent:text', {
+      conversationId: secondConversation,
+      text: 'second response ',
+    });
+  });
+
   it('persists only redacted assistant content with classifications', (): void => {
     const { gateway, brain } = buildGateway();
     const client = {
@@ -147,7 +197,8 @@ describe('ChatGateway redaction boundary', (): void => {
       data: { user: { id: 'user-1' } },
       emit: vi.fn(),
     };
-    gateway.clientSessions.set(client.id, {
+    gateway.clientSessions.set(clientConversationKey(client.id, CONVERSATION_ID), {
+      clientId: client.id,
       conversationId: CONVERSATION_ID,
       cleanup: vi.fn(),
       assistantText: CANARY,