chore: nest js best practices

backend/package.json

@@ -31,6 +31,8 @@
     "@nestjs/terminus": "^11.0.0",
     "@prisma/adapter-pg": "^7.0.0",
     "@prisma/client": "^7.0.0",
+    "class-transformer": "^0.5.1",
+    "class-validator": "^0.14.4",
     "dotenv": "^17.0.0",
     "express-prom-bundle": "^8.0.0",
     "helmet": "^8.0.0",

backend/src/app.module.ts

@@ -2,7 +2,7 @@ import 'dotenv/config'
 import type { MiddlewareConsumer } from '@nestjs/common'
 import { Module, RequestMethod } from '@nestjs/common'
 import { HTTPLoggerMiddleware } from './middleware/req.res.logger'
-import { PrismaService } from './prisma.service'
+import { PrismaModule } from './prisma.module'
 import { ConfigModule } from '@nestjs/config'
 import { UsersModule } from './users/users.module'
 import { AppService } from './app.service'
@@ -12,9 +12,9 @@ import { TerminusModule } from '@nestjs/terminus'
 import { HealthController } from './health.controller'
 
 @Module({
-  imports: [ConfigModule.forRoot(), TerminusModule, UsersModule],
+  imports: [ConfigModule.forRoot({ isGlobal: true }), TerminusModule, PrismaModule, UsersModule],
   controllers: [AppController, MetricsController, HealthController],
-  providers: [AppService, PrismaService],
+  providers: [AppService],
 })
 export class AppModule {
   // let's add a middleware on all routes

backend/src/app.ts

@@ -4,7 +4,7 @@ import { AppModule } from './app.module'
 import { customLogger } from './common/logger.config'
 import type { NestExpressApplication } from '@nestjs/platform-express'
 import helmet from 'helmet'
-import { VersioningType } from '@nestjs/common'
+import { ValidationPipe, VersioningType } from '@nestjs/common'
 import { metricsMiddleware } from './middleware/prom'
 
 /**
@@ -15,6 +15,16 @@ export async function bootstrap() {
     logger: customLogger,
   })
   app.use(helmet())
+  app.useGlobalPipes(
+    new ValidationPipe({
+      whitelist: true,
+      forbidNonWhitelisted: true,
+      transform: true,
+      transformOptions: {
+        enableImplicitConversion: true,
+      },
+    }),
+  )
   app.enableCors()
   app.set('trust proxy', 1)
   app.use(metricsMiddleware)

backend/src/health.controller.ts

@@ -5,8 +5,8 @@ import type { PrismaClient } from '../generated/prisma/client.js'
 @Controller('health')
 export class HealthController {
   constructor(
-    private health: HealthCheckService,
-    private prisma: PrismaHealthIndicator,
+    private readonly health: HealthCheckService,
+    private readonly prisma: PrismaHealthIndicator,
     private readonly prismaService: PrismaService,
   ) {}
 

backend/src/middleware/req.res.logger.ts

@@ -4,7 +4,7 @@ import { Injectable, Logger } from '@nestjs/common'
 
 @Injectable()
 export class HTTPLoggerMiddleware implements NestMiddleware {
-  private logger = new Logger('HTTP')
+  private readonly logger = new Logger('HTTP')
 
   use(request: Request, response: Response, next: NextFunction): void {
     const { method, originalUrl } = request

backend/src/prisma.service.spec.ts

@@ -14,7 +14,7 @@ describe('PrismaService', () => {
   })
 
   afterEach(async () => {
-    await service.$disconnect()
+    await service.onModuleDestroy()
   })
 
   it('should be defined', () => {

backend/src/prisma.service.ts

@@ -21,13 +21,9 @@ const PrismaClientWithLogs = PrismaClient as unknown as new (
 
 @Injectable()
 class PrismaService extends PrismaClientWithLogs implements OnModuleInit, OnModuleDestroy {
-  private logger = new Logger('PRISMA')
-  private static instance: PrismaService
-  private pool!: Pool
+  private readonly logger = new Logger('PRISMA')
+  private readonly pool: Pool
   constructor() {
-    if (PrismaService.instance) {
-      return PrismaService.instance
-    }
     const pool = new Pool({ connectionString: dataSourceURL })
     const adapter = new PrismaPg(pool, { schema: DB_SCHEMA })
     super({
@@ -41,7 +37,6 @@ class PrismaService extends PrismaClientWithLogs implements OnModuleInit, OnModu
       ],
     })
     this.pool = pool
-    PrismaService.instance = this
   }
 
   async onModuleInit() {
@@ -59,6 +54,7 @@ class PrismaService extends PrismaClientWithLogs implements OnModuleInit, OnModu
 
   async onModuleDestroy() {
     await this.$disconnect()
+    await this.pool.end()
   }
 }
 

backend/src/users/dto/search-users-query.dto.ts

@@ -0,0 +1,25 @@
+import { Type } from 'class-transformer'
+import { IsInt, IsJSON, IsOptional, Max, Min } from 'class-validator'
+
+export class SearchUsersQueryDto {
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(1)
+  page = 1
+
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(1)
+  @Max(200)
+  limit = 10
+
+  @IsOptional()
+  @IsJSON()
+  sort = '[]'
+
+  @IsOptional()
+  @IsJSON()
+  filter = '[]'
+}

backend/src/users/dto/update-user.dto.ts

@@ -1,3 +1,4 @@
+import { PartialType } from '@nestjs/swagger'
 import { CreateUserDto } from './create-user.dto'
 
-export class UpdateUserDto extends CreateUserDto {}
+export class UpdateUserDto extends PartialType(CreateUserDto) {}

backend/src/users/dto/user.dto.ts

@@ -1,21 +1,29 @@
 import { ApiProperty } from '@nestjs/swagger'
+import { Transform } from 'class-transformer'
+import { IsEmail, IsInt, IsNotEmpty, IsPositive, IsString, MaxLength } from 'class-validator'
 
 export class UserDto {
   @ApiProperty({
     description: 'The ID of the user',
-    // default: '9999',
   })
+  @IsInt()
+  @IsPositive()
   id!: number
 
   @ApiProperty({
     description: 'The name of the user',
-    // default: 'username',
   })
+  @Transform(({ value }) => (typeof value === 'string' ? value.trim() : value))
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(200)
   name!: string
 
   @ApiProperty({
     description: 'The contact email of the user',
-    default: '',
   })
+  @Transform(({ value }) => (typeof value === 'string' ? value.trim() : value))
+  @IsEmail()
+  @MaxLength(200)
   email!: string
 }