I am trying to send the exception using nestjs websocket based on conditions, tried using
throw new WsException('Invalid data');
but not sending any exception
Here is the sample code
import WebSocket from 'ws';
import {
SubscribeMessage,
WebSocketGateway,
WsException,
} from '@nestjs/websockets';
@WebSocketGateway({ path: '/api' })
export class MainGateway {
@SubscribeMessage('message')
handleMessage(client: WebSocket, payload: any) {
if (payload.id === 4) {
throw new WsException('Invalid Data');
}
client.send(JSON.stringify({ id: payload.id }));
}
}
and I'm creating the connection using angular here is the code snippet
export class WsComponent implements OnInit {
public value!: number;
public subject$ = webSocket('ws://localhost:3000/api');
ngOnInit(): void {
const event = { event: 'message', data: { id: 4 } };
this.subject$.subscribe({
next: (v: any) => (this.value = v.id),
error: (e) => console.error(e),
complete: () => console.info('complete'),
});
this.subject$.next(event);
}
}
Please help me to solve the issue
I have struggled with same issue. I believe the issus is with BaseWsExceptionFilter and its usage of soket.emit. I've come up with following:
import { ArgumentsHost, Catch, HttpException } from "@nestjs/common";
import { BaseWsExceptionFilter, WsException } from "@nestjs/websockets";
@Catch(WsException, HttpException)
export class WebsocketExceptionsFilter extends BaseWsExceptionFilter {
catch(exception: WsException | HttpException, host: ArgumentsHost) {
const client = host.switchToWs().getClient() as WebSocket;
const data = host.switchToWs().getData();
const error = exception instanceof WsException ? exception.getError() : exception.getResponse();
const details = error instanceof Object ? { ...error } : { message: error };
client.send(JSON.stringify({
event: "error",
data: {
id: (client as any).id,
rid: data.rid,
...details
}
}));
}
}
Pretty much sure extends BaseWsExceptionFilter is redundant as I did't use anything of that class. And then I applied it to my gateway:
@WebSocketGateway()
@UseFilters(WebsocketExceptionsFilter)
@UsePipes(new ValidationPipe({ transform: true }))
export class FeedGateway implements OnGatewayConnection, OnGatewayDisconnect {
}
This helped me to receive following error:
{"event":"error","data":{"id":"7a784ce568767a1016090c6a","rid":"connect","statusCode":400,"message":["language must be a valid enum value"],"error":"Bad Request"}}