add area loader

src/crags/crags.module.ts

@@ -70,6 +70,7 @@ import { RouteLoader } from './loaders/route.loader';
 import { RouteEvent } from './entities/route-event.entity';
 import { Parking } from './entities/parking.entity';
 import { ParkingsService } from './services/parkings.service';
+import { AreaLoader } from './loaders/area.loader';
 
 @Module({
   imports: [
@@ -143,6 +144,7 @@ import { ParkingsService } from './services/parkings.service';
     MailService,
     SummaryQueueConsumer,
     ConfigService,
+    AreaLoader,
     CragLoader,
     RouteLoader,
     ParkingsService,

src/crags/loaders/area.loader.ts

@@ -0,0 +1,24 @@
+import DataLoader from 'dataloader';
+import { Injectable } from '@nestjs/common';
+import { NestDataLoader } from '../../core/interceptors/data-loader.interceptor';
+import { Area } from '../entities/area.entity';
+import { AreasService } from '../services/areas.service';
+
+@Injectable()
+export class AreaLoader implements NestDataLoader<string, Area> {
+  constructor(private readonly areasService: AreasService) {}
+
+  generateDataLoader(): DataLoader<string, Area> {
+    return new DataLoader<string, Area>(async (keys) => {
+      const areas = await this.areasService.findByIds(keys.map((k) => k));
+
+      const areasMap: { [key: string]: Area } = {};
+
+      areas.forEach((area) => {
+        areasMap[area.id] = area;
+      });
+
+      return keys.map((areaId) => areasMap[areaId] ?? null);
+    });
+  }
+}

src/crags/resolvers/areas.resolver.ts

@@ -1,4 +1,11 @@
-import { Resolver, Mutation, Args, Query } from '@nestjs/graphql';
+import {
+  Resolver,
+  Mutation,
+  Args,
+  Query,
+  ResolveField,
+  Parent,
+} from '@nestjs/graphql';
 import { Area } from '../entities/area.entity';
 import { Roles } from '../../auth/decorators/roles.decorator';
 import { UseFilters, UseInterceptors } from '@nestjs/common';
@@ -8,6 +15,11 @@ import { CreateAreaInput } from '../dtos/create-area.input';
 import { AreasService } from '../services/areas.service';
 import { AllowAny } from '../../auth/decorators/allow-any.decorator';
 import { NotFoundFilter } from '../filters/not-found.filter';
+import { Country } from '../entities/country.entity';
+import { Loader } from '../../core/interceptors/data-loader.interceptor';
+import { CountryLoader } from '../loaders/country.loader';
+import { Crag } from '../entities/crag.entity';
+import DataLoader from 'dataloader';
 
 @Resolver(() => Area)
 export class AreasResolver {
@@ -44,4 +56,13 @@ export class AreasResolver {
   async deleteArea(@Args('id') id: string): Promise<boolean> {
     return this.areasService.delete(id);
   }
+
+  @ResolveField('country', () => Country)
+  async getCountry(
+    @Parent() crag: Crag,
+    @Loader(CountryLoader)
+    loader: DataLoader<Country['id'], Country>,
+  ): Promise<Country> {
+    return loader.load(crag.countryId);
+  }
 }

src/crags/resolvers/crags.resolver.ts

@@ -44,6 +44,8 @@ import { NotificationService } from '../../notification/services/notification.se
 import { ForeignKeyConstraintFilter } from '../filters/foreign-key-constraint.filter';
 import { ImagesService } from '../services/images.service';
 import { Roles } from '../../auth/decorators/roles.decorator';
+import { Area } from '../entities/area.entity';
+import { AreaLoader } from '../loaders/area.loader';
 
 @Resolver(() => Crag)
 @UseInterceptors(DataLoaderInterceptor)
@@ -218,6 +220,15 @@ export class CragsResolver {
     return loader.load(crag.countryId);
   }
 
+  @ResolveField('area', () => Area, { nullable: true })
+  async getArea(
+    @Parent() crag: Area,
+    @Loader(AreaLoader)
+    loader: DataLoader<Area['id'], Area>,
+  ): Promise<Area> {
+    return crag.areaId ? loader.load(crag.areaId) : null;
+  }
+
   @Mutation(() => Boolean)
   @Roles('admin')
   @UseGuards(UserAuthGuard)

src/crags/services/areas.service.ts

@@ -25,6 +25,11 @@ export class AreasService {
     return this.areasRepository.findOneByOrFail({ slug });
   }
 
+  findByIds(ids: string[]): Promise<Area[]> {
+    const qb = this.areasRepository.createQueryBuilder('area');
+    return qb.whereInIds(ids).getMany();
+  }
+
   find(params: FindAreasInput = {}): Promise<Area[]> {
     const options: FindManyOptions = {
       order: {},