refactor(server): events (#13003)

* refactor(server): events

* chore: better type

---------

Co-authored-by: Daniel Dietzler <mail@ddietzler.dev>

server/src/repositories/event.repository.ts

@@ -1,6 +1,5 @@
 import { Inject, Injectable } from '@nestjs/common';
 import { ModuleRef } from '@nestjs/core';
-import { EventEmitter2 } from '@nestjs/event-emitter';
 import {
   OnGatewayConnection,
   OnGatewayDisconnect,
@@ -13,16 +12,17 @@ import {
   ArgsOf,
   ClientEventMap,
   EmitEvent,
-  EmitHandler,
+  EventItem,
   IEventRepository,
-  ServerEvent,
-  ServerEventMap,
+  serverEvents,
+  ServerEvents,
 } from 'src/interfaces/event.interface';
 import { ILoggerRepository } from 'src/interfaces/logger.interface';
 import { AuthService } from 'src/services/auth.service';
 import { Instrumentation } from 'src/utils/instrumentation';
+import { handlePromiseError } from 'src/utils/misc';
 
-type EmitHandlers = Partial<{ [T in EmitEvent]: EmitHandler<T>[] }>;
+type EmitHandlers = Partial<{ [T in EmitEvent]: Array<EventItem<T>> }>;
 
 @Instrumentation()
 @WebSocketGateway({
@@ -39,7 +39,6 @@ export class EventRepository implements OnGatewayConnection, OnGatewayDisconnect
 
   constructor(
     private moduleRef: ModuleRef,
-    private eventEmitter: EventEmitter2,
     @Inject(ILoggerRepository) private logger: ILoggerRepository,
   ) {
     this.logger.setContext(EventRepository.name);
@@ -48,14 +47,10 @@ export class EventRepository implements OnGatewayConnection, OnGatewayDisconnect
   afterInit(server: Server) {
     this.logger.log('Initialized websocket server');
 
-    for (const event of Object.values(ServerEvent)) {
-      if (event === ServerEvent.WEBSOCKET_CONNECT) {
-        continue;
-      }
-
-      server.on(event, (data: unknown) => {
+    for (const event of serverEvents) {
+      server.on(event, (...args: ArgsOf<any>) => {
         this.logger.debug(`Server event: ${event} (receive)`);
-        this.eventEmitter.emit(event, data);
+        handlePromiseError(this.onEvent({ name: event, args, server: true }), this.logger);
       });
     }
   }
@@ -72,7 +67,7 @@ export class EventRepository implements OnGatewayConnection, OnGatewayDisconnect
       if (auth.session) {
         await client.join(auth.session.id);
       }
-      this.serverSend(ServerEvent.WEBSOCKET_CONNECT, { userId: auth.user.id });
+      await this.onEvent({ name: 'websocket.connect', args: [{ userId: auth.user.id }], server: false });
     } catch (error: Error | any) {
       this.logger.error(`Websocket connection error: ${error}`, error?.stack);
       client.emit('error', 'unauthorized');
@@ -85,18 +80,29 @@ export class EventRepository implements OnGatewayConnection, OnGatewayDisconnect
     await client.leave(client.nsp.name);
   }
 
-  on<T extends EmitEvent>(event: T, handler: EmitHandler<T>): void {
+  on<T extends EmitEvent>(item: EventItem<T>): void {
+    const event = item.event;
+
     if (!this.emitHandlers[event]) {
       this.emitHandlers[event] = [];
     }
 
-    this.emitHandlers[event].push(handler);
+    this.emitHandlers[event].push(item);
   }
 
   async emit<T extends EmitEvent>(event: T, ...args: ArgsOf<T>): Promise<void> {
-    const handlers = this.emitHandlers[event] || [];
-    for (const handler of handlers) {
-      await handler(...args);
+    return this.onEvent({ name: event, args, server: false });
+  }
+
+  private async onEvent<T extends EmitEvent>(event: { name: T; args: ArgsOf<T>; server: boolean }): Promise<void> {
+    const handlers = this.emitHandlers[event.name] || [];
+    for (const { handler, server } of handlers) {
+      // exclude handlers that ignore server events
+      if (!server && event.server) {
+        continue;
+      }
+
+      await handler(...event.args);
     }
   }
 
@@ -108,9 +114,8 @@ export class EventRepository implements OnGatewayConnection, OnGatewayDisconnect
     this.server?.emit(event, data);
   }
 
-  serverSend<E extends keyof ServerEventMap>(event: E, data: ServerEventMap[E]) {
+  serverSend<T extends ServerEvents>(event: T, ...args: ArgsOf<T>): void {
     this.logger.debug(`Server event: ${event} (send)`);
-    this.server?.serverSideEmit(event, data);
-    return this.eventEmitter.emit(event, data);
+    this.server?.serverSideEmit(event, ...args);
   }
 }