feat: title of session (#12971)

fix AI-253

packages/backend/server/src/__tests__/__snapshots__/copilot.spec.ts.md

@@ -330,3 +330,45 @@ Generated by [AVA](https://avajs.dev).
       ],
       {},
     ]
+
+## should handle generateSessionTitle correctly under various conditions
+
+> should generate title when conditions are met
+
+    {
+      chatWithPromptCalled: undefined,
+      exists: true,
+      title: 'What is Machine Learning?',
+    }
+
+> should not generate title when session already has title
+
+    {
+      chatWithPromptCalled: false,
+      exists: true,
+      title: 'Existing Title',
+    }
+
+> should not generate title when no user messages exist
+
+    {
+      chatWithPromptCalled: false,
+      exists: true,
+      title: null,
+    }
+
+> should not generate title when no assistant messages exist
+
+    {
+      chatWithPromptCalled: false,
+      exists: true,
+      title: null,
+    }
+
+> should use correct prompt for title generation
+
+    {
+      content: `[user]: Explain quantum computing briefly␊
+      [assistant]: Quantum computing uses quantum mechanics principles.`,
+      promptName: 'Summary as title',
+    }

packages/backend/server/src/__tests__/copilot.spec.ts

@@ -11,7 +11,11 @@ import { EventBus, JobQueue } from '../base';
 import { ConfigModule } from '../base/config';
 import { AuthService } from '../core/auth';
 import { QuotaModule } from '../core/quota';
-import { ContextCategories, WorkspaceModel } from '../models';
+import {
+  ContextCategories,
+  CopilotSessionModel,
+  WorkspaceModel,
+} from '../models';
 import { CopilotModule } from '../plugins/copilot';
 import { CopilotContextService } from '../plugins/copilot/context';
 import {
@@ -57,12 +61,13 @@ import { MockCopilotProvider } from './mocks';
 import { createTestingModule, TestingModule } from './utils';
 import { WorkflowTestCases } from './utils/copilot';
 
-const test = ava as TestFn<{
+type Context = {
   auth: AuthService;
   module: TestingModule;
   db: PrismaClient;
   event: EventBus;
   workspace: WorkspaceModel;
+  copilotSession: CopilotSessionModel;
   context: CopilotContextService;
   prompt: PromptService;
   transcript: CopilotTranscriptionService;
@@ -78,7 +83,8 @@ const test = ava as TestFn<{
     html: CopilotCheckHtmlExecutor;
     json: CopilotCheckJsonExecutor;
   };
-}>;
+};
+const test = ava as TestFn<Context>;
 let userId: string;
 
 test.before(async t => {
@@ -119,6 +125,7 @@ test.before(async t => {
   const db = module.get(PrismaClient);
   const event = module.get(EventBus);
   const workspace = module.get(WorkspaceModel);
+  const copilotSession = module.get(CopilotSessionModel);
   const prompt = module.get(PromptService);
   const factory = module.get(CopilotProviderFactory);
 
@@ -136,6 +143,7 @@ test.before(async t => {
   t.context.db = db;
   t.context.event = event;
   t.context.workspace = workspace;
+  t.context.copilotSession = copilotSession;
   t.context.prompt = prompt;
   t.context.factory = factory;
   t.context.session = session;
@@ -1752,3 +1760,168 @@ test('should be able to manage workspace embedding', async t => {
     t.is(ret2.length, 0, 'should not match workspace context');
   }
 });
+
+test('should handle generateSessionTitle correctly under various conditions', async t => {
+  const { prompt, session, workspace, copilotSession } = t.context;
+
+  await prompt.set('test', 'model', [{ role: 'user', content: '{{content}}' }]);
+  const createSession = async (
+    options: {
+      userMessage?: string;
+      assistantMessage?: string;
+      existingTitle?: string;
+    } = {}
+  ) => {
+    const ws = await workspace.create(userId);
+    const sessionId = await session.create({
+      docId: 'test-doc',
+      workspaceId: ws.id,
+      userId,
+      promptName: 'test',
+      pinned: false,
+    });
+
+    if (options.existingTitle) {
+      await copilotSession.update({
+        userId,
+        sessionId,
+        title: options.existingTitle,
+      });
+    }
+
+    const chatSession = await session.get(sessionId);
+    if (chatSession) {
+      if (options.userMessage) {
+        chatSession.push({
+          role: 'user',
+          content: options.userMessage,
+          createdAt: new Date(),
+        });
+      }
+      if (options.assistantMessage) {
+        chatSession.push({
+          role: 'assistant',
+          content: options.assistantMessage,
+          createdAt: new Date(),
+        });
+      }
+      await chatSession.save();
+    }
+
+    return sessionId;
+  };
+
+  const testCases = [
+    {
+      name: 'should generate title when conditions are met',
+      setup: () =>
+        createSession({
+          userMessage: 'What is machine learning?',
+          assistantMessage:
+            'Machine learning is a subset of artificial intelligence.',
+        }),
+      mockFn: () => 'What is Machine Learning?',
+      expectSnapshot: true,
+    },
+    {
+      name: 'should not generate title when session already has title',
+      setup: () =>
+        createSession({
+          userMessage: 'Test message',
+          assistantMessage: 'Test response',
+          existingTitle: 'Existing Title',
+        }),
+      mockFn: () => 'New Title',
+      expectSnapshot: true,
+      expectNotCalled: true,
+    },
+    {
+      name: 'should not generate title when no user messages exist',
+      setup: () =>
+        createSession({ assistantMessage: 'Hello! How can I help you?' }),
+      mockFn: () => 'New Title',
+      expectSnapshot: true,
+      expectNotCalled: true,
+    },
+    {
+      name: 'should not generate title when no assistant messages exist',
+      setup: () => createSession({ userMessage: 'What is AI?' }),
+      mockFn: () => 'New Title',
+      expectSnapshot: true,
+      expectNotCalled: true,
+    },
+    {
+      name: 'should handle errors gracefully',
+      setup: () =>
+        createSession({
+          userMessage: 'Test question',
+          assistantMessage: 'Test answer',
+        }),
+      mockFn: () => {
+        throw new Error('Mock error for testing');
+      },
+      expectError: 'Mock error for testing',
+    },
+  ];
+
+  for (const testCase of testCases) {
+    const sessionId = await testCase.setup();
+    let chatWithPromptCalled = false;
+
+    const mockStub = Sinon.stub(session, 'chatWithPrompt').callsFake(
+      async () => {
+        chatWithPromptCalled = true;
+        return testCase.mockFn();
+      }
+    );
+
+    if (testCase.expectError) {
+      await t.throwsAsync(
+        () => session.generateSessionTitle({ sessionId }),
+        { message: testCase.expectError },
+        testCase.name
+      );
+    } else {
+      await session.generateSessionTitle({ sessionId });
+
+      if (testCase.expectSnapshot) {
+        const sessionState = await session.getSession(sessionId);
+        t.snapshot(
+          {
+            chatWithPromptCalled: testCase.expectNotCalled
+              ? chatWithPromptCalled
+              : undefined,
+            title: sessionState?.title,
+            exists: !!sessionState,
+          },
+          testCase.name
+        );
+      }
+    }
+
+    mockStub.restore();
+  }
+
+  {
+    const sessionId = await createSession({
+      userMessage: 'Explain quantum computing briefly',
+      assistantMessage: 'Quantum computing uses quantum mechanics principles.',
+    });
+
+    let capturedArgs: any[] = [];
+    Sinon.stub(session, 'chatWithPrompt').callsFake(async (...args) => {
+      capturedArgs = args;
+      return 'Quantum Computing Explained';
+    });
+
+    await session.generateSessionTitle({ sessionId });
+
+    t.snapshot(
+      {
+        promptName: capturedArgs[0],
+        content: capturedArgs[1]?.content,
+      },
+      'should use correct prompt for title generation'
+    );
+  }
+});

packages/backend/server/src/__tests__/models/copilot-context.spec.ts

@@ -58,6 +58,7 @@ test.beforeEach(async t => {
     workspaceId: workspace.id,
     docId,
     userId: user.id,
+    title: null,
     promptName: 'prompt-name',
     promptAction: null,
   });

packages/backend/server/src/__tests__/models/copilot-session.spec.ts

@@ -82,6 +82,7 @@ const createTestSession = async (
     workspaceId: workspace.id,
     docId: null,
     pinned: false,
+    title: null,
     promptName: TEST_PROMPTS.NORMAL,
     promptAction: null,
     ...overrides,
@@ -297,6 +298,7 @@ test('should pin and unpin sessions', async t => {
       promptName: 'test-prompt',
       promptAction: null,
       pinned: true,
+      title: null,
     });
 
     const firstSession = await copilotSession.get(firstSessionId);
@@ -312,6 +314,7 @@ test('should pin and unpin sessions', async t => {
       promptName: 'test-prompt',
       promptAction: null,
       pinned: true,
+      title: null,
     });
 
     const sessionStatesAfterSecondPin = await getSessionStates(db, [
@@ -796,6 +799,7 @@ test('should handle fork and session attachment operations', async t => {
       workspaceId: workspace.id,
       docId: forkConfig.docId,
       pinned: forkConfig.pinned,
+      title: null,
       parentSessionId,
       prompt: { name: TEST_PROMPTS.NORMAL, action: null, model: 'gpt-4.1' },
       messages: [

packages/backend/server/src/models/copilot-session.ts

@@ -50,6 +50,7 @@ type PureChatSession = {
   workspaceId: string;
   docId?: string | null;
   pinned?: boolean;
+  title: string | null;
   messages?: ChatMessage[];
   // connect ids
   userId: string;
@@ -82,7 +83,7 @@ type UpdateChatSessionMessage = ChatSessionBaseState & {
 };
 
 export type UpdateChatSessionOptions = ChatSessionBaseState &
-  Pick<Partial<ChatSession>, 'docId' | 'pinned' | 'promptName'>;
+  Pick<Partial<ChatSession>, 'docId' | 'pinned' | 'promptName' | 'title'>;
 
 export type UpdateChatSession = ChatSessionBaseState & UpdateChatSessionOptions;
 
@@ -254,7 +255,7 @@ export class CopilotSessionModel extends BaseModel {
     return (await this.db.aiSession.findUnique({
       where: { ...where, id: sessionId, deletedAt: null },
       select,
-    })) as Prisma.AiSessionGetPayload<{ select: Select }>;
+    })) as Prisma.AiSessionGetPayload<{ select: Select }> | null;
   }
 
   @Transactional()
@@ -266,6 +267,7 @@ export class CopilotSessionModel extends BaseModel {
       docId: true,
       pinned: true,
       parentSessionId: true,
+      title: true,
       messages: {
         select: {
           id: true,
@@ -331,6 +333,7 @@ export class CopilotSessionModel extends BaseModel {
         docId: true,
         parentSessionId: true,
         pinned: true,
+        title: true,
         promptName: true,
         tokenCost: true,
         createdAt: true,
@@ -373,7 +376,7 @@ export class CopilotSessionModel extends BaseModel {
 
   @Transactional()
   async update(options: UpdateChatSessionOptions): Promise<string> {
-    const { userId, sessionId, docId, promptName, pinned } = options;
+    const { userId, sessionId, docId, promptName, pinned, title } = options;
     const session = await this.getExists(
       sessionId,
       {
@@ -419,7 +422,7 @@ export class CopilotSessionModel extends BaseModel {
 
     await this.db.aiSession.update({
       where: { id: sessionId },
-      data: { docId, promptName, pinned },
+      data: { docId, promptName, pinned, title },
     });
 
     return sessionId;
@@ -522,17 +525,29 @@ export class CopilotSessionModel extends BaseModel {
     if (!id) {
       throw new CopilotSessionNotFound();
     }
-    const ids = await this.getMessages(id, { id: true, role: true }).then(
-      roles =>
-        roles
-          .slice(
-            roles.findLastIndex(({ role }) => role === AiPromptRole.user) +
-              (removeLatestUserMessage ? 0 : 1)
-          )
-          .map(({ id }) => id)
-    );
+    const messages = await this.getMessages(id, { id: true, role: true });
+    const ids = messages
+      .slice(
+        messages.findLastIndex(({ role }) => role === AiPromptRole.user) +
+          (removeLatestUserMessage ? 0 : 1)
+      )
+      .map(({ id }) => id);
+
     if (ids.length) {
       await this.db.aiSessionMessage.deleteMany({ where: { id: { in: ids } } });
+
+      // clear the title if there only one round of conversation left
+      const remainingMessages = await this.getMessages(id, { role: true });
+      const userMessageCount = remainingMessages.filter(
+        m => m.role === AiPromptRole.user
+      ).length;
+
+      if (userMessageCount <= 1) {
+        await this.db.aiSession.update({
+          where: { id },
+          data: { title: null },
+        });
+      }
     }
   }
 

packages/backend/server/src/plugins/copilot/resolver.ts

@@ -67,7 +67,9 @@ class CreateChatSessionInput {
 }
 
 @InputType()
-class UpdateChatSessionInput implements Omit<UpdateChatSession, 'userId'> {
+class UpdateChatSessionInput
+  implements Omit<UpdateChatSession, 'userId' | 'title'>
+{
   @Field(() => String)
   sessionId!: string;
 
@@ -336,6 +338,9 @@ export class CopilotSessionType {
   @Field(() => Boolean)
   pinned!: boolean;
 
+  @Field(() => String, { nullable: true })
+  title!: string | null;
+
   @Field(() => ID, { nullable: true })
   parentSessionId!: string | null;
 
@@ -653,6 +658,7 @@ export class CopilotResolver {
       parentSessionId: session.parentSessionId,
       docId: session.docId,
       pinned: session.pinned,
+      title: session.title,
       promptName: session.prompt.name,
       model: session.prompt.model,
       optionalModels: session.prompt.optionalModels,

packages/backend/server/src/plugins/copilot/session.ts

@@ -1,6 +1,7 @@
 import { randomUUID } from 'node:crypto';
 
 import { Injectable, Logger } from '@nestjs/common';
+import { ModuleRef } from '@nestjs/core';
 import { Transactional } from '@nestjs-cls/transactional';
 import { AiPromptRole } from '@prisma/client';
 
@@ -11,6 +12,9 @@ import {
   CopilotQuotaExceeded,
   CopilotSessionInvalidInput,
   CopilotSessionNotFound,
+  JobQueue,
+  NoCopilotProviderAvailable,
+  OnJob,
 } from '../../base';
 import { QuotaService } from '../../core/quota';
 import {
@@ -22,7 +26,12 @@ import {
 } from '../../models';
 import { ChatMessageCache } from './message';
 import { PromptService } from './prompt';
-import { PromptMessage, PromptParams } from './providers';
+import {
+  CopilotProviderFactory,
+  ModelOutputType,
+  PromptMessage,
+  PromptParams,
+} from './providers';
 import {
   type ChatHistory,
   type ChatMessage,
@@ -33,6 +42,14 @@ import {
   type SubmittedMessage,
 } from './types';
 
+declare global {
+  interface Jobs {
+    'copilot.session.generateTitle': {
+      sessionId: string;
+    };
+  }
+}
+
 export class ChatSession implements AsyncDisposable {
   private stashMessageCount = 0;
   constructor(
@@ -224,10 +241,12 @@ export class ChatSessionService {
   private readonly logger = new Logger(ChatSessionService.name);
 
   constructor(
+    private readonly moduleRef: ModuleRef,
+    private readonly models: Models,
+    private readonly jobs: JobQueue,
     private readonly quota: QuotaService,
     private readonly messageCache: ChatMessageCache,
-    private readonly prompt: PromptService,
-    private readonly models: Models
+    private readonly prompt: PromptService
   ) {}
 
   async getSession(sessionId: string): Promise<ChatSessionState | undefined> {
@@ -244,6 +263,7 @@ export class ChatSessionService {
       workspaceId: session.workspaceId,
       docId: session.docId,
       pinned: session.pinned,
+      title: session.title,
       parentSessionId: session.parentSessionId,
       prompt,
       messages: messages.success ? messages.data : [],
@@ -282,6 +302,7 @@ export class ChatSessionService {
           workspaceId: session.workspaceId,
           docId: session.docId,
           pinned: session.pinned,
+          title: session.title,
           parentSessionId: session.parentSessionId,
           prompt,
         };
@@ -303,6 +324,7 @@ export class ChatSessionService {
           workspaceId,
           docId,
           pinned,
+          title,
           promptName,
           tokenCost,
           messages,
@@ -347,6 +369,7 @@ export class ChatSessionService {
                 workspaceId,
                 docId,
                 pinned,
+                title,
                 action: prompt.action || null,
                 tokens: tokenCost,
                 createdAt,
@@ -418,6 +441,7 @@ export class ChatSessionService {
         ...options,
         sessionId,
         prompt,
+        title: null,
         messages: [],
         // when client create chat session, we always find root session
         parentSessionId: null,
@@ -520,8 +544,78 @@ export class ChatSessionService {
     if (state) {
       return new ChatSession(this.messageCache, state, async state => {
         await this.models.copilotSession.updateMessages(state);
+        if (!state.prompt.action) {
+          await this.jobs.add('copilot.session.generateTitle', { sessionId });
+        }
       });
     }
     return null;
   }
+
+  // public for test mock
+  async chatWithPrompt(
+    promptName: string,
+    message: Partial<PromptMessage>
+  ): Promise<string> {
+    const prompt = await this.prompt.get(promptName);
+    if (!prompt) {
+      throw new CopilotPromptNotFound({ name: promptName });
+    }
+
+    const cond = { modelId: prompt.model };
+    const msg = { role: 'user' as const, content: '', ...message };
+    const config = Object.assign({}, prompt.config);
+
+    const provider = await this.moduleRef
+      .get(CopilotProviderFactory)
+      .getProvider({
+        outputType: ModelOutputType.Text,
+        modelId: prompt.model,
+      });
+
+    if (!provider) {
+      throw new NoCopilotProviderAvailable();
+    }
+
+    return provider.text(cond, [...prompt.finish({}), msg], config);
+  }
+
+  @OnJob('copilot.session.generateTitle')
+  async generateSessionTitle(job: Jobs['copilot.session.generateTitle']) {
+    const { sessionId } = job;
+
+    try {
+      const session = await this.models.copilotSession.get(sessionId);
+      if (!session) {
+        this.logger.warn(
+          `Session ${sessionId} not found when generating title`
+        );
+        return;
+      }
+      const { userId, title, messages } = session;
+      if (
+        title ||
+        !messages.length ||
+        messages.filter(m => m.role === 'user').length === 0 ||
+        messages.filter(m => m.role === 'assistant').length === 0
+      ) {
+        return;
+      }
+
+      {
+        const title = await this.chatWithPrompt('Summary as title', {
+          content: session.messages
+            .map(m => `[${m.role}]: ${m.content}`)
+            .join('\n'),
+        });
+        await this.models.copilotSession.update({ userId, sessionId, title });
+      }
+    } catch (error) {
+      console.error(
+        `Failed to generate title for session ${sessionId}:`,
+        error
+      );
+      throw error;
+    }
+  }
 }

packages/backend/server/src/plugins/copilot/types.ts

@@ -50,6 +50,7 @@ export const ChatHistorySchema = z
     workspaceId: z.string(),
     docId: z.string().nullable(),
     pinned: z.boolean(),
+    title: z.string().nullable(),
     action: z.string().nullable(),
     tokens: z.number(),
     messages: z.array(ChatMessageSchema),
@@ -85,6 +86,7 @@ export interface ChatSessionForkOptions
 
 export interface ChatSessionState
   extends Omit<ChatSessionOptions, 'promptName'> {
+  title: string | null;
   // connect ids
   sessionId: string;
   parentSessionId: string | null;

packages/backend/server/src/schema.gql

@@ -324,6 +324,7 @@ type CopilotSessionType {
   parentSessionId: ID
   pinned: Boolean!
   promptName: String!
+  title: String
 }
 
 type CopilotWorkspaceConfig {