JSON parse error - `Unexpected token 'N', "No connect"... is not valid JSON`

[mirkobertone]

Hi!
I have an architecture with an apigateway(grpc client) and a microservice(grpc server) .
When the grpc server is down, the GrpcToHttpInterceptor in controller catch this error:

{
  code: 14,
  details: "No connection established. Last error: connect ECONNREFUSED 0.0.0.0:50051 (2024-04-09T08:38:21.111Z)",
  metadata: {
    internalRepr: {
    },
    options: {
    },
  },
}

The JSON.parse(err.details) brake in this case. Is it possible the if statement isn't checking in the right way?
I've also check with debug and I attach a screen

Here my controller in apigateway and interceptor

@UseInterceptors(GrpcToHttpInterceptor)
@Controller('/api/actors')
export class ActorController {
  constructor(
    private readonly actorsService: ApiActorService,
    private readonly logger: WinstonLoggerService,
  ) {}

  @Post()
  @ApiOperation({ summary: 'Create an actor' })
  create(@Body() actor: CreateActorRequest, @GetTraceId() traceID: string): Promise<ActorResponse> {
    return this.actorsService.create(actor, { traceID });
  }

}

[mirkobertone]

I created a PR if need it #14

[rajibkuet07]

I think a proper solution for this issue would be to change the exception message in HttpToGrpcInterceptor as follows-

return throwError(
    () =>
        new RpcException({
            message: JSON.stringify({
                error: exception.message,
                type: typeof exception.message === 'string' ? 'string' : 'object',
                exceptionName: RpcException.name,
            }),
            code: statusCode,
        }),
);

As you are expecting an error object in the GrpcToHttpInterceptor interceptor.

It would work for all sorts of HTTP exceptions from gRPC clients.