NestJS query + Mongoose bugs?

[mareksuscak]

Hi there,

I've been trying to use this lib with Mongoose and followed the documentation and official examples but I'm struggling with a few things that I'd appreciate getting some help on from someone more experienced to see if I'm doing something wrong or if I'm running into a bug:

1. Mongoose + Offset pagination works with caveats

Pagination works in general but whenever I request the totalCount property from the "read many" resolver, I get the following error: Cannot return null for non-nullable field BrokerConnection.totalCount.

// broker.module.ts
import { Module } from '@nestjs/common';
import { NestjsQueryGraphQLModule } from '@ptc-org/nestjs-query-graphql';
import { NestjsQueryMongooseModule } from '@ptc-org/nestjs-query-mongoose';
import { Broker, BrokerSchema } from '@app/persistence/models';

import { BrokerDto } from './dto/broker.dto';
import { CreateBrokerDto } from './dto/broker-create.dto';
import { UpdateBrokerDto } from './dto/broker-update.dto';
import { BrokerResolver } from './broker.resolver';
import { BrokerService } from './broker.service';

@Module({
  providers: [BrokerResolver],
  imports: [
    NestjsQueryGraphQLModule.forFeature({
      imports: [
        NestjsQueryMongooseModule.forFeature([
          { document: Broker, name: Broker.name, schema: BrokerSchema },
        ]),
      ],
      services: [BrokerService],
      resolvers: [
        {
          DTOClass: BrokerDto,
          CreateDTOClass: CreateBrokerDto,
          UpdateDTOClass: UpdateBrokerDto,
          EntityClass: Broker,
          ServiceClass: BrokerService,
          enableTotalCount: true,
          enableAggregate: true,
        },
      ],
    }),
  ],
})
export class BrokerModule {}

// broker.dto.ts
import { Field, ID, ObjectType } from '@nestjs/graphql';
import type {
  CreateManyInputType,
  CreateOneInputType, UpdateManyInputType, UpdateOneInputType} from '@ptc-org/nestjs-query-graphql';
import {
  FilterableField,
  IDField,
  ObjectId,
  PagingStrategies,
  QueryOptions,
} from '@ptc-org/nestjs-query-graphql';
import mongoose from 'mongoose';

@ObjectType('Broker')
@QueryOptions({
  pagingStrategy: PagingStrategies.OFFSET,
  enableTotalCount: true,
})
export class BrokerDto {
  @ObjectId()
  _id: mongoose.Types.ObjectId;

  @IDField(() => ID)
  id!: string;

  @FilterableField()
  firstName: string;

  @FilterableField()
  lastName: string;
}

2. Mongoose + Custom CRUD resolver

When I remove the auto-generated resolver from the module and replace it with a barebones custom resolver with no extra methods, I get a similar error where the fields aren't being retrieved anymore: Cannot return null for non-nullable field Broker.firstName.

// broker.module.ts
import { Module } from '@nestjs/common';
import { NestjsQueryGraphQLModule } from '@ptc-org/nestjs-query-graphql';
import { NestjsQueryMongooseModule } from '@ptc-org/nestjs-query-mongoose';
import { Broker, BrokerSchema } from '@app/persistence/models';

import { BrokerDto } from './dto/broker.dto';
import { BrokerResolver } from './broker.resolver';
import { BrokerService } from './broker.service';

@Module({
  providers: [BrokerResolver],
  imports: [
    NestjsQueryGraphQLModule.forFeature({
      imports: [
        NestjsQueryMongooseModule.forFeature([
          { document: Broker, name: Broker.name, schema: BrokerSchema },
        ]),
      ],

      dtos: [{ DTOClass: BrokerDto }],
      services: [BrokerService],
  ],
})
export class BrokerModule {}

// broker.resolver.ts
import { InjectQueryService, QueryService } from '@ptc-org/nestjs-query-core';
import { CRUDResolver } from '@ptc-org/nestjs-query-graphql';
import { Resolver } from '@nestjs/graphql';
import { Broker } from '@app/persistence/models';

import { BrokerDto } from './dto/broker.dto';

@Resolver(() => BrokerDto)
export class BrokerResolver extends CRUDResolver(BrokerDto) {
  constructor(
    @InjectQueryService(Broker) service: QueryService<BrokerDto>
  ) {
    super(service);
  }

// package.json
"@nestjs/mongoose": "10.0.2",
"@ptc-org/nestjs-query-core": "4.3.3",
"@ptc-org/nestjs-query-graphql": "4.3.3",
"@ptc-org/nestjs-query-mongoose": "4.3.3",
"mongodb": "5.9.2", 
"mongoose": "7.6.7",

[TriPSs]

Could be a bug inside the nestjs-query-mongoose, could you add an example + test to the repo that has this issue, than I can take look on how to fix it.

[mareksuscak]

Will do, thanks for getting back so fast!

[mareksuscak]

@TriPSs while creating a minimum reproducible example, I figured out what was causing the errors - it was the global ClassSerializerInterceptor

// main.ts

// This breaks NestJS query
app.useGlobalInterceptors(
  new ClassSerializerInterceptor(app.get(Reflector))
);

Once commented out. Everything started working as expected including the totalCount and custom resolvers + custom services.

[TriPSs]

Aah, yea somehow that makes sense as totalCount is not a "real" variable but a get totalCount so the count query is not done when the field is not retrieved.