diff --git a/packages/data-center/src/datacenter.ts b/packages/data-center/src/datacenter.ts
index 47d4480e71..cd4bbf905a 100644
--- a/packages/data-center/src/datacenter.ts
+++ b/packages/data-center/src/datacenter.ts
@@ -1,23 +1,25 @@
-import { Workspaces } from './workspaces';
-import type { WorkspacesChangeEvent } from './workspaces';
+import { WorkspaceMetaCollection } from './workspace-meta-collection.js';
+import type { WorkspaceMetaCollectionChangeEvent } from './workspace-meta-collection';
 import { Workspace as BlocksuiteWorkspace } from '@blocksuite/store';
 import { BaseProvider } from './provider/base';
 import { LocalProvider } from './provider/local/local';
 import { AffineProvider } from './provider';
-import type { WorkspaceMeta } from './types';
+import type { Message, WorkspaceMeta } from './types';
 import assert from 'assert';
 import { getLogger } from './logger';
 import { applyUpdate, encodeStateAsUpdate } from 'yjs';
 import { createBlocksuiteWorkspace } from './utils/index.js';
+import { MessageCenter } from './message/message';
 
 /**
  * @class DataCenter
  * @classdesc Data center is made for managing different providers for business
  */
 export class DataCenter {
-  private readonly _workspaces = new Workspaces();
+  private readonly _workspaceMetaCollection = new WorkspaceMetaCollection();
   private readonly _logger = getLogger('dc');
   private _workspaceInstances: Map<string, BlocksuiteWorkspace> = new Map();
+  private _messageCenter = new MessageCenter();
   /**
    * A mainProvider must exist as the only data trustworthy source.
    */
@@ -30,19 +32,16 @@ export class DataCenter {
 
   static async init(debug: boolean): Promise<DataCenter> {
     const dc = new DataCenter(debug);
+    const getInitParams = () => {
+      return {
+        logger: dc._logger,
+        workspaces: dc._workspaceMetaCollection.createScope(),
+        messageCenter: dc._messageCenter,
+      };
+    };
     // TODO: switch different provider
-    dc.registerProvider(
-      new LocalProvider({
-        logger: dc._logger,
-        workspaces: dc._workspaces.createScope(),
-      })
-    );
-    dc.registerProvider(
-      new AffineProvider({
-        logger: dc._logger,
-        workspaces: dc._workspaces.createScope(),
-      })
-    );
+    dc.registerProvider(new LocalProvider(getInitParams()));
+    dc.registerProvider(new AffineProvider(getInitParams()));
 
     return dc;
   }
@@ -69,7 +68,7 @@ export class DataCenter {
   }
 
   public get workspaces() {
-    return this._workspaces.workspaces;
+    return this._workspaceMetaCollection.workspaces;
   }
 
   public async refreshWorkspaces() {
@@ -104,7 +103,7 @@ export class DataCenter {
    * @param {string} workspaceId workspace id
    */
   public async deleteWorkspace(workspaceId: string) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     assert(provider, `Workspace exists, but we couldn't find its provider.`);
@@ -116,7 +115,7 @@ export class DataCenter {
    * @param {string} workspaceId workspace id
    */
   private _getBlocksuiteWorkspace(workspaceId: string) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     return (
       this._workspaceInstances.get(workspaceId) ||
@@ -150,7 +149,7 @@ export class DataCenter {
    * @returns {Promise<BlocksuiteWorkspace>}
    */
   public async loadWorkspace(workspaceId: string) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     const currentProvider = this.providerMap.get(workspaceInfo.provider);
     if (currentProvider) {
@@ -181,9 +180,9 @@ export class DataCenter {
    * @param {Function} callback callback function
    */
   public async onWorkspacesChange(
-    callback: (workspaces: WorkspacesChangeEvent) => void
+    callback: (workspaces: WorkspaceMetaCollectionChangeEvent) => void
   ) {
-    this._workspaces.on('change', callback);
+    this._workspaceMetaCollection.on('change', callback);
   }
 
   /**
@@ -206,7 +205,7 @@ export class DataCenter {
       update.avatar = avatar;
     }
     // may run for change workspace meta
-    const workspaceInfo = this._workspaces.find(workspace.room);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspace.room);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     provider?.updateWorkspaceMeta(workspace.room, update);
@@ -218,7 +217,7 @@ export class DataCenter {
    * @param id workspace id
    */
   public async leaveWorkspace(workspaceId: string) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     if (provider) {
@@ -228,7 +227,7 @@ export class DataCenter {
   }
 
   public async setWorkspacePublish(workspaceId: string, isPublish: boolean) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     if (provider) {
@@ -237,7 +236,7 @@ export class DataCenter {
   }
 
   public async inviteMember(id: string, email: string) {
-    const workspaceInfo = this._workspaces.find(id);
+    const workspaceInfo = this._workspaceMetaCollection.find(id);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     if (provider) {
@@ -250,7 +249,7 @@ export class DataCenter {
    * @param {number} permissionId permission id
    */
   public async removeMember(workspaceId: string, permissionId: number) {
-    const workspaceInfo = this._workspaces.find(workspaceId);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspaceId);
     assert(workspaceInfo, 'Workspace not found');
     const provider = this.providerMap.get(workspaceInfo.provider);
     if (provider) {
@@ -281,7 +280,7 @@ export class DataCenter {
     providerId: string
   ) {
     assert(workspace.room, 'No workspace id');
-    const workspaceInfo = this._workspaces.find(workspace.room);
+    const workspaceInfo = this._workspaceMetaCollection.find(workspace.room);
     assert(workspaceInfo, 'Workspace not found');
     if (workspaceInfo.provider === providerId) {
       this._logger('Workspace provider is same');
@@ -371,4 +370,8 @@ export class DataCenter {
     const blobStorage = await workspace.blobs;
     return (await blobStorage?.set(blob)) || '';
   }
+
+  onMessage(cb: (message: Message) => void) {
+    return this._messageCenter.onMessage(cb);
+  }
 }
diff --git a/packages/data-center/src/index.ts b/packages/data-center/src/index.ts
index 96c281f373..bc816cb3f7 100644
--- a/packages/data-center/src/index.ts
+++ b/packages/data-center/src/index.ts
@@ -29,3 +29,4 @@ export type { DataCenter };
 export type { AccessTokenMessage } from './provider/affine/apis';
 export * from './types';
 export { getLogger } from './logger';
+export * from './message';
diff --git a/packages/data-center/src/message/code.ts b/packages/data-center/src/message/code.ts
new file mode 100644
index 0000000000..271ffc8d38
--- /dev/null
+++ b/packages/data-center/src/message/code.ts
@@ -0,0 +1,3 @@
+export enum MessageCode {
+  loginError,
+}
diff --git a/packages/data-center/src/message/index.ts b/packages/data-center/src/message/index.ts
new file mode 100644
index 0000000000..b04581df15
--- /dev/null
+++ b/packages/data-center/src/message/index.ts
@@ -0,0 +1,2 @@
+export { MessageCenter } from './message';
+export { MessageCode } from './code';
diff --git a/packages/data-center/src/message/message.ts b/packages/data-center/src/message/message.ts
new file mode 100644
index 0000000000..7a59f15bf4
--- /dev/null
+++ b/packages/data-center/src/message/message.ts
@@ -0,0 +1,24 @@
+import { Observable } from 'lib0/observable';
+import { Message } from 'src/types';
+import { MessageCode } from './code';
+
+export class MessageCenter extends Observable<string> {
+  constructor() {
+    super();
+  }
+
+  public send(message: MessageCode) {
+    this.emit('message', [message]);
+  }
+
+  public onMessage(callback: (message: Message) => void) {
+    this.on('message', callback);
+  }
+
+  private messages: Record<number, Message> = {
+    [MessageCode.loginError]: {
+      code: MessageCode.loginError,
+      message: 'Login failed',
+    },
+  };
+}
diff --git a/packages/data-center/src/provider/affine/__tests__/affine.spec.ts b/packages/data-center/src/provider/affine/__tests__/affine.spec.ts
index 3208c6d54d..f60af0d139 100644
--- a/packages/data-center/src/provider/affine/__tests__/affine.spec.ts
+++ b/packages/data-center/src/provider/affine/__tests__/affine.spec.ts
@@ -1,6 +1,6 @@
 import { test, expect } from '@playwright/test';
 import { AffineProvider } from '../affine.js';
-import { Workspaces } from '../../../workspaces/index.js';
+// import { Workspaces } from '../../../workspaces/index.js';
 import { apis } from './mock-apis.js';
 import 'fake-indexeddb/auto';
 
diff --git a/packages/data-center/src/provider/affine/affine.ts b/packages/data-center/src/provider/affine/affine.ts
index b01766d906..537f54cd74 100644
--- a/packages/data-center/src/provider/affine/affine.ts
+++ b/packages/data-center/src/provider/affine/affine.ts
@@ -11,6 +11,7 @@ import { WebsocketProvider } from './sync.js';
 import { getApis } from './apis/index.js';
 import type { Apis, WorkspaceDetail, Callback } from './apis';
 import { setDefaultAvatar } from '../utils.js';
+import { MessageCode } from 'src/message/code.js';
 
 export interface AffineProviderConstructorParams
   extends ProviderConstructorParams {
@@ -196,7 +197,10 @@ export class AffineProvider extends BaseProvider {
         return;
       }
     }
-    await this._apis.signInWithGoogle?.();
+    const user = await this._apis.signInWithGoogle?.();
+    if (!user) {
+      this._messageCenter.send(MessageCode.loginError);
+    }
   }
 
   public override async getUserInfo(): Promise<User | undefined> {
diff --git a/packages/data-center/src/provider/base.ts b/packages/data-center/src/provider/base.ts
index f7a056110c..be075fefe6 100644
--- a/packages/data-center/src/provider/base.ts
+++ b/packages/data-center/src/provider/base.ts
@@ -1,6 +1,7 @@
 import { Workspace as BlocksuiteWorkspace, uuidv4 } from '@blocksuite/store';
+import { MessageCenter } from 'src/message';
 import { Logger, User, WorkspaceInfo, WorkspaceMeta } from '../types';
-import type { WorkspacesScope } from '../workspaces';
+import type { WorkspaceMetaCollectionScope } from '../workspace-meta-collection';
 
 const defaultLogger = () => {
   return;
@@ -8,17 +9,24 @@ const defaultLogger = () => {
 
 export interface ProviderConstructorParams {
   logger?: Logger;
-  workspaces: WorkspacesScope;
+  workspaces: WorkspaceMetaCollectionScope;
+  messageCenter: MessageCenter;
 }
 
 export class BaseProvider {
   public readonly id: string = 'base';
-  protected _workspaces!: WorkspacesScope;
+  protected _workspaces!: WorkspaceMetaCollectionScope;
   protected _logger!: Logger;
+  protected _messageCenter!: MessageCenter;
 
-  public constructor({ logger, workspaces }: ProviderConstructorParams) {
+  public constructor({
+    logger,
+    workspaces,
+    messageCenter,
+  }: ProviderConstructorParams) {
     this._logger = (logger || defaultLogger) as Logger;
     this._workspaces = workspaces;
+    this._messageCenter = messageCenter;
   }
 
   /**
diff --git a/packages/data-center/src/provider/local/local.spec.ts b/packages/data-center/src/provider/local/local.spec.ts
index 5d388470a6..eff462ef86 100644
--- a/packages/data-center/src/provider/local/local.spec.ts
+++ b/packages/data-center/src/provider/local/local.spec.ts
@@ -1,13 +1,13 @@
 import { test, expect } from '@playwright/test';
-import { Workspaces } from '../../workspaces/index.js';
+import { WorkspaceMetaCollection } from '../../workspace-meta-collection.js';
 import { LocalProvider } from './local.js';
 import { createBlocksuiteWorkspace } from '../../utils/index.js';
 import 'fake-indexeddb/auto';
 
 test.describe.serial('local provider', () => {
-  const workspaces = new Workspaces();
+  const workspaceMetaCollection = new WorkspaceMetaCollection();
   const provider = new LocalProvider({
-    workspaces: workspaces.createScope(),
+    workspaces: workspaceMetaCollection.createScope(),
   });
 
   const workspaceName = 'workspace-test';
@@ -25,30 +25,30 @@ test.describe.serial('local provider', () => {
       avatar: 'avatar-url-test',
     });
 
-    expect(workspaces.workspaces.length).toEqual(1);
-    expect(workspaces.workspaces[0].name).toEqual(workspaceName);
+    expect(workspaceMetaCollection.workspaces.length).toEqual(1);
+    expect(workspaceMetaCollection.workspaces[0].name).toEqual(workspaceName);
   });
 
   test('workspace list cache', async () => {
-    const workspaces1 = new Workspaces();
+    const workspacesMetaCollection1 = new WorkspaceMetaCollection();
     const provider1 = new LocalProvider({
-      workspaces: workspaces1.createScope(),
+      workspaces: workspacesMetaCollection1.createScope(),
     });
     await provider1.loadWorkspaces();
-    expect(workspaces1.workspaces.length).toEqual(1);
-    expect(workspaces1.workspaces[0].name).toEqual(workspaceName);
-    expect(workspaces1.workspaces[0].id).toEqual(workspaceId);
+    expect(workspacesMetaCollection1.workspaces.length).toEqual(1);
+    expect(workspacesMetaCollection1.workspaces[0].name).toEqual(workspaceName);
+    expect(workspacesMetaCollection1.workspaces[0].id).toEqual(workspaceId);
   });
 
   test('update workspace', async () => {
     await provider.updateWorkspaceMeta(workspaceId!, {
       name: '1111',
     });
-    expect(workspaces.workspaces[0].name).toEqual('1111');
+    expect(workspaceMetaCollection.workspaces[0].name).toEqual('1111');
   });
 
   test('delete workspace', async () => {
-    expect(workspaces.workspaces.length).toEqual(1);
+    expect(workspaceMetaCollection.workspaces.length).toEqual(1);
     /**
      * FIXME
      * If we don't wrap setTimeout,
@@ -56,8 +56,8 @@ test.describe.serial('local provider', () => {
      * InvalidStateError: An operation was called on an object on which it is not allowed or at a time when it is not allowed. Also occurs if a request is made on a source object that has been deleted or removed. Use TransactionInactiveError or ReadOnlyError when possible, as they are more specific variations of InvalidStateError.
      * */
     setTimeout(async () => {
-      await provider.deleteWorkspace(workspaces.workspaces[0].id);
-      expect(workspaces.workspaces.length).toEqual(0);
+      await provider.deleteWorkspace(workspaceMetaCollection.workspaces[0].id);
+      expect(workspaceMetaCollection.workspaces.length).toEqual(0);
     }, 10);
   });
 });
diff --git a/packages/data-center/src/provider/utils.ts b/packages/data-center/src/provider/utils.ts
index b0a08b92d7..d8e5f6d058 100644
--- a/packages/data-center/src/provider/utils.ts
+++ b/packages/data-center/src/provider/utils.ts
@@ -8,8 +8,7 @@ export const setDefaultAvatar = async (
   const blob = await getDefaultHeadImgBlob(blocksuiteWorkspace.meta.name);
   const blobStorage = await blocksuiteWorkspace.blobs;
   assert(blobStorage, 'No blob storage');
-  const blobId = await blobStorage.set(blob);
-  const avatar = await blobStorage.get(blobId);
+  const avatar = await blobStorage.set(blob);
   if (avatar) {
     blocksuiteWorkspace.meta.setAvatar(avatar);
   }
diff --git a/packages/data-center/src/types/index.ts b/packages/data-center/src/types/index.ts
index 1155ee325a..29e3a2f255 100644
--- a/packages/data-center/src/types/index.ts
+++ b/packages/data-center/src/types/index.ts
@@ -21,3 +21,8 @@ export type User = {
 export type WorkspaceMeta = Pick<WorkspaceInfo, 'name' | 'avatar'>;
 
 export type Logger = ReturnType<typeof getLogger>;
+
+export type Message = {
+  code: number;
+  message: string;
+};
diff --git a/packages/data-center/src/workspaces/workspaces.spec.ts b/packages/data-center/src/workspace-meta-collection.spec.ts
similarity index 64%
rename from packages/data-center/src/workspaces/workspaces.spec.ts
rename to packages/data-center/src/workspace-meta-collection.spec.ts
index c7925fdfff..afb3eb65f5 100644
--- a/packages/data-center/src/workspaces/workspaces.spec.ts
+++ b/packages/data-center/src/workspace-meta-collection.spec.ts
@@ -1,14 +1,14 @@
 import { test, expect } from '@playwright/test';
-import { Workspaces } from './workspaces.js';
-import type { WorkspacesChangeEvent } from './workspaces';
+import { WorkspaceMetaCollection } from './workspace-meta-collection.js';
+import type { WorkspaceMetaCollectionChangeEvent } from './workspace-meta-collection';
 
-test.describe.serial('workspaces observable', () => {
-  const workspaces = new Workspaces();
+test.describe.serial('workspace meta collection observable', () => {
+  const workspaces = new WorkspaceMetaCollection();
 
   const scope = workspaces.createScope();
 
   test('add workspace', () => {
-    workspaces.once('change', (event: WorkspacesChangeEvent) => {
+    workspaces.once('change', (event: WorkspaceMetaCollectionChangeEvent) => {
       expect(event.added?.id).toEqual('123');
     });
     scope.add({
@@ -30,7 +30,7 @@ test.describe.serial('workspaces observable', () => {
   });
 
   test('update workspace', () => {
-    workspaces.once('change', (event: WorkspacesChangeEvent) => {
+    workspaces.once('change', (event: WorkspaceMetaCollectionChangeEvent) => {
       expect(event.updated?.name).toEqual('demo');
     });
     scope.update('123', { name: 'demo' });
@@ -42,7 +42,7 @@ test.describe.serial('workspaces observable', () => {
   });
 
   test('delete workspace', () => {
-    workspaces.once('change', (event: WorkspacesChangeEvent) => {
+    workspaces.once('change', (event: WorkspaceMetaCollectionChangeEvent) => {
       expect(event.deleted?.id).toEqual('123');
     });
     scope.remove('123');
diff --git a/packages/data-center/src/workspaces/workspaces.ts b/packages/data-center/src/workspace-meta-collection.ts
similarity index 86%
rename from packages/data-center/src/workspaces/workspaces.ts
rename to packages/data-center/src/workspace-meta-collection.ts
index d248951dc7..6b7ce4a350 100644
--- a/packages/data-center/src/workspaces/workspaces.ts
+++ b/packages/data-center/src/workspace-meta-collection.ts
@@ -1,7 +1,7 @@
 import { Observable } from 'lib0/observable';
-import type { WorkspaceInfo, WorkspaceMeta } from '../types';
+import type { WorkspaceInfo, WorkspaceMeta } from './types';
 
-export interface WorkspacesScope {
+export interface WorkspaceMetaCollectionScope {
   get: (workspaceId: string) => WorkspaceInfo | undefined;
   list: () => WorkspaceInfo[];
   add: (workspace: WorkspaceInfo) => void;
@@ -10,13 +10,13 @@ export interface WorkspacesScope {
   update: (workspaceId: string, workspaceMeta: Partial<WorkspaceMeta>) => void;
 }
 
-export interface WorkspacesChangeEvent {
+export interface WorkspaceMetaCollectionChangeEvent {
   added?: WorkspaceInfo;
   deleted?: WorkspaceInfo;
   updated?: WorkspaceInfo;
 }
 
-export class Workspaces extends Observable<'change'> {
+export class WorkspaceMetaCollection extends Observable<'change'> {
   private _workspacesMap = new Map<string, WorkspaceInfo>();
 
   get workspaces(): WorkspaceInfo[] {
@@ -27,7 +27,7 @@ export class Workspaces extends Observable<'change'> {
     return this._workspacesMap.get(workspaceId);
   }
 
-  createScope(): WorkspacesScope {
+  createScope(): WorkspaceMetaCollectionScope {
     const scopedWorkspaceIds = new Set<string>();
 
     const get = (workspaceId: string) => {
@@ -47,7 +47,7 @@ export class Workspaces extends Observable<'change'> {
       this.emit('change', [
         {
           added: workspace,
-        } as WorkspacesChangeEvent,
+        } as WorkspaceMetaCollectionChangeEvent,
       ]);
     };
 
@@ -69,7 +69,7 @@ export class Workspaces extends Observable<'change'> {
         this.emit('change', [
           {
             deleted: workspace,
-          } as WorkspacesChangeEvent,
+          } as WorkspaceMetaCollectionChangeEvent,
         ]);
       }
       return true;
@@ -99,7 +99,7 @@ export class Workspaces extends Observable<'change'> {
       this.emit('change', [
         {
           updated: this._workspacesMap.get(workspaceId),
-        } as WorkspacesChangeEvent,
+        } as WorkspaceMetaCollectionChangeEvent,
       ]);
     };
 
diff --git a/packages/data-center/src/workspaces/index.ts b/packages/data-center/src/workspaces/index.ts
deleted file mode 100644
index a8ef316e8d..0000000000
--- a/packages/data-center/src/workspaces/index.ts
+++ /dev/null
@@ -1,2 +0,0 @@
-export { Workspaces } from './workspaces.js';
-export type { WorkspacesScope, WorkspacesChangeEvent } from './workspaces';