refactor(infra): directory structure (#4615)

packages/backend/server/src/modules/sync/events/events.gateway.ts

@@ -0,0 +1,212 @@
+import { Logger } from '@nestjs/common';
+import {
+  ConnectedSocket,
+  MessageBody,
+  OnGatewayConnection,
+  OnGatewayDisconnect,
+  SubscribeMessage,
+  WebSocketGateway,
+  WebSocketServer,
+} from '@nestjs/websockets';
+import { Server, Socket } from 'socket.io';
+import { encodeStateAsUpdate, encodeStateVector } from 'yjs';
+
+import { Metrics } from '../../../metrics/metrics';
+import { DocID } from '../../../utils/doc';
+import { Auth, CurrentUser } from '../../auth';
+import { DocManager } from '../../doc';
+import { UserType } from '../../users';
+import { PermissionService } from '../../workspaces/permission';
+import { Permission } from '../../workspaces/types';
+
+@WebSocketGateway({
+  cors: process.env.NODE_ENV !== 'production',
+  transports: ['websocket'],
+})
+export class EventsGateway implements OnGatewayConnection, OnGatewayDisconnect {
+  protected logger = new Logger(EventsGateway.name);
+  private connectionCount = 0;
+
+  constructor(
+    private readonly docManager: DocManager,
+    private readonly metric: Metrics,
+    private readonly permissions: PermissionService
+  ) {}
+
+  @WebSocketServer()
+  server!: Server;
+
+  handleConnection() {
+    this.connectionCount++;
+    this.metric.socketIOConnectionGauge(this.connectionCount, {});
+  }
+
+  handleDisconnect() {
+    this.connectionCount--;
+    this.metric.socketIOConnectionGauge(this.connectionCount, {});
+  }
+
+  @Auth()
+  @SubscribeMessage('client-handshake')
+  async handleClientHandShake(
+    @CurrentUser() user: UserType,
+    @MessageBody() workspaceId: string,
+    @ConnectedSocket() client: Socket
+  ) {
+    this.metric.socketIOEventCounter(1, { event: 'client-handshake' });
+    const endTimer = this.metric.socketIOEventTimer({
+      event: 'client-handshake',
+    });
+
+    const canWrite = await this.permissions.tryCheck(
+      workspaceId,
+      user.id,
+      Permission.Write
+    );
+    if (canWrite) await client.join(workspaceId);
+
+    endTimer();
+    return canWrite;
+  }
+
+  @SubscribeMessage('client-leave')
+  async handleClientLeave(
+    @MessageBody() workspaceId: string,
+    @ConnectedSocket() client: Socket
+  ) {
+    this.metric.socketIOEventCounter(1, { event: 'client-leave' });
+    const endTimer = this.metric.socketIOEventTimer({
+      event: 'client-leave',
+    });
+    await client.leave(workspaceId);
+    endTimer();
+  }
+
+  @SubscribeMessage('client-update')
+  async handleClientUpdate(
+    @MessageBody()
+    {
+      workspaceId,
+      guid,
+      update,
+    }: {
+      workspaceId: string;
+      guid: string;
+      update: string;
+    },
+    @ConnectedSocket() client: Socket
+  ) {
+    this.metric.socketIOEventCounter(1, { event: 'client-update' });
+    const endTimer = this.metric.socketIOEventTimer({ event: 'client-update' });
+
+    if (!client.rooms.has(workspaceId)) {
+      this.logger.verbose(
+        `Client ${client.id} tried to push update to workspace ${workspaceId} without joining it first`
+      );
+      endTimer();
+      return;
+    }
+
+    const docId = new DocID(guid, workspaceId);
+    client
+      .to(docId.workspace)
+      .emit('server-update', { workspaceId, guid, update });
+
+    const buf = Buffer.from(update, 'base64');
+
+    await this.docManager.push(docId.workspace, docId.guid, buf);
+    endTimer();
+  }
+
+  @Auth()
+  @SubscribeMessage('doc-load')
+  async loadDoc(
+    @ConnectedSocket() client: Socket,
+    @CurrentUser() user: UserType,
+    @MessageBody()
+    {
+      workspaceId,
+      guid,
+      stateVector,
+    }: {
+      workspaceId: string;
+      guid: string;
+      stateVector?: string;
+    }
+  ): Promise<{ missing: string; state?: string } | false> {
+    this.metric.socketIOEventCounter(1, { event: 'doc-load' });
+    const endTimer = this.metric.socketIOEventTimer({ event: 'doc-load' });
+    if (!client.rooms.has(workspaceId)) {
+      const canRead = await this.permissions.tryCheck(workspaceId, user.id);
+      if (!canRead) {
+        endTimer();
+        return false;
+      }
+    }
+
+    const docId = new DocID(guid, workspaceId);
+    const doc = await this.docManager.get(docId.workspace, docId.guid);
+
+    if (!doc) {
+      endTimer();
+      return false;
+    }
+
+    const missing = Buffer.from(
+      encodeStateAsUpdate(
+        doc,
+        stateVector ? Buffer.from(stateVector, 'base64') : undefined
+      )
+    ).toString('base64');
+    const state = Buffer.from(encodeStateVector(doc)).toString('base64');
+
+    endTimer();
+    return {
+      missing,
+      state,
+    };
+  }
+
+  @SubscribeMessage('awareness-init')
+  async handleInitAwareness(
+    @MessageBody() workspaceId: string,
+    @ConnectedSocket() client: Socket
+  ) {
+    this.metric.socketIOEventCounter(1, { event: 'awareness-init' });
+    const endTimer = this.metric.socketIOEventTimer({
+      event: 'init-awareness',
+    });
+    if (client.rooms.has(workspaceId)) {
+      client.to(workspaceId).emit('new-client-awareness-init');
+    } else {
+      this.logger.verbose(
+        `Client ${client.id} tried to init awareness for workspace ${workspaceId} without joining it first`
+      );
+    }
+    endTimer();
+  }
+
+  @SubscribeMessage('awareness-update')
+  async handleHelpGatheringAwareness(
+    @MessageBody() message: { workspaceId: string; awarenessUpdate: string },
+    @ConnectedSocket() client: Socket
+  ) {
+    this.metric.socketIOEventCounter(1, { event: 'awareness-update' });
+    const endTimer = this.metric.socketIOEventTimer({
+      event: 'awareness-update',
+    });
+
+    if (client.rooms.has(message.workspaceId)) {
+      client.to(message.workspaceId).emit('server-awareness-broadcast', {
+        ...message,
+      });
+    } else {
+      this.logger.verbose(
+        `Client ${client.id} tried to update awareness for workspace ${message.workspaceId} without joining it first`
+      );
+    }
+
+    endTimer();
+    return 'ack';
+  }
+}

packages/backend/server/src/modules/sync/events/events.module.ts

@@ -0,0 +1,11 @@
+import { Module } from '@nestjs/common';
+
+import { DocModule } from '../../doc';
+import { PermissionService } from '../../workspaces/permission';
+import { EventsGateway } from './events.gateway';
+
+@Module({
+  imports: [DocModule.forFeature()],
+  providers: [EventsGateway, PermissionService],
+})
+export class EventsModule {}

packages/backend/server/src/modules/sync/index.ts

@@ -0,0 +1,8 @@
+import { Module } from '@nestjs/common';
+
+import { EventsModule } from './events/events.module';
+
+@Module({
+  imports: [EventsModule],
+})
+export class SyncModule {}

packages/backend/server/src/modules/sync/redis-adapter.ts

@@ -0,0 +1,37 @@
+import { IoAdapter } from '@nestjs/platform-socket.io';
+import { createAdapter } from '@socket.io/redis-adapter';
+import { Redis } from 'ioredis';
+import { ServerOptions } from 'socket.io';
+
+export class RedisIoAdapter extends IoAdapter {
+  private adapterConstructor: ReturnType<typeof createAdapter> | undefined;
+
+  async connectToRedis(
+    host: string,
+    port: number,
+    username: string,
+    password: string,
+    db: number
+  ): Promise<void> {
+    const pubClient = new Redis(port, host, {
+      username,
+      password,
+      db,
+    });
+    pubClient.on('error', err => {
+      console.error(err);
+    });
+    const subClient = pubClient.duplicate();
+    subClient.on('error', err => {
+      console.error(err);
+    });
+
+    this.adapterConstructor = createAdapter(pubClient, subClient);
+  }
+
+  override createIOServer(port: number, options?: ServerOptions): any {
+    const server = super.createIOServer(port, options);
+    server.adapter(this.adapterConstructor);
+    return server;
+  }
+}

packages/backend/server/src/modules/sync/utils.ts

@@ -0,0 +1,11 @@
+export function assertExists<T>(
+  val: T | null | undefined,
+  message: string | Error = 'val does not exist'
+): asserts val is T {
+  if (val === null || val === undefined) {
+    if (message instanceof Error) {
+      throw message;
+    }
+    throw new Error(message);
+  }
+}