Add Configuration Module with Environment Schema Validation

drips/.env.example

@@ -7,4 +7,4 @@ SMTP_PASSWORD=your-app-password
 SMTP_FROM=skills <noreply@hospital.com>
 
 # Application URL
-APP_URL=http://localhost:3000
+APP_URL=http://localhost:3000

drips/README.md

@@ -93,6 +93,40 @@ Nest is an MIT-licensed open source project. It can grow thanks to the sponsors
 - Website - [https://nestjs.com](https://nestjs.com/)
 - Twitter - [@nestframework](https://twitter.com/nestframework)
 
+## Configuration
+
+The application uses a centralized configuration module with environment variable validation using Joi.
+
+### Environment Files
+The application loads environment variables from `.env` files. You can use different files for different environments:
+- `.env`: Default environment variables
+- `.env.development`: Development-specific variables
+- `.env.test`: Test-specific variables
+
+### Required Variables
+See [.env.example](.env.example) for the list of required environment variables. Key variables include:
+- `PORT`: Server port (default: 3000)
+- `NODE_ENV`: Environment mode (`development`, `production`, `test`)
+- `DATABASE_HOST`: Database host
+- `DATABASE_PORT`: Database port
+- `DATABASE_USER`: Database user
+- `DATABASE_PASSWORD`: Database password
+- `DATABASE_NAME`: Database name
+
+### Validation
+Environment variables are validated at startup. If any required variable is missing or malformed, the application will fail to boot with a descriptive error message.
+
+### Usage
+To access configuration in other modules, inject `AppConfigService`:
+
+```typescript
+import { AppConfigService } from './config/config.service';
+
+constructor(private configService: AppConfigService) {
+  const port = this.configService.port;
+}
+```
+
 ## License
 
 Nest is [MIT licensed](https://github.com/nestjs/nest/blob/master/LICENSE).

drips/package.json

@@ -25,8 +25,10 @@
     "@nestjs/core": "^11.0.1",
     "@nestjs/platform-express": "^11.0.1",
     "@nestjs/typeorm": "^11.0.0",
+    "@types/joi": "^17.2.2",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.14.3",
+    "joi": "^18.0.2",
     "pg": "^8.17.2",
     "reflect-metadata": "^0.2.2",
     "rxjs": "^7.8.1",

drips/src/app.module.ts

@@ -1,28 +1,26 @@
 import { Module } from '@nestjs/common';
-import { ConfigModule, ConfigService } from '@nestjs/config';
 import { TypeOrmModule } from '@nestjs/typeorm';
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
+import { AppConfigModule } from './config/config.module';
+import { AppConfigService } from './config/config.service';
 
 @Module({
   imports: [
-    ConfigModule.forRoot({
-      isGlobal: true,
-      envFilePath: '.env',
-    }),
+    AppConfigModule,
     TypeOrmModule.forRootAsync({
-      inject: [ConfigService],
-      useFactory: (configService: ConfigService) => ({
+      inject: [AppConfigService],
+      useFactory: (configService: AppConfigService) => ({
         type: 'postgres',
-        host: configService.get('DATABASE_HOST', 'localhost'),
-        port: configService.get('DATABASE_PORT', 5432),
-        username: configService.get('DATABASE_USER', 'postgres'),
-        password: configService.get('DATABASE_PASSWORD', 'postgres'),
-        database: configService.get('DATABASE_NAME', 'drips_db'),
+        host: configService.databaseHost,
+        port: configService.databasePort,
+        username: configService.databaseUser,
+        password: configService.databasePassword,
+        database: configService.databaseName,
         entities: ['dist/**/*.entity{.ts,.js}'],
         migrations: ['dist/migrations/*{.ts,.js}'],
-        synchronize: configService.get('NODE_ENV') === 'development',
-        logging: configService.get('NODE_ENV') === 'development',
+        synchronize: configService.nodeEnv === 'development',
+        logging: configService.nodeEnv === 'development',
         // namingStrategy: new (require('typeorm').SnakeNamingStrategy)(),
       }),
     }),

drips/src/config/config.module.ts

@@ -0,0 +1,21 @@
+import { Module, Global } from '@nestjs/common';
+import { ConfigModule as NestConfigModule } from '@nestjs/config';
+import { AppConfigService } from './config.service';
+import { envValidationSchema } from './env.validation';
+
+@Global()
+@Module({
+  imports: [
+    NestConfigModule.forRoot({
+      isGlobal: true,
+      validationSchema: envValidationSchema,
+      validationOptions: {
+        allowUnknown: true,
+        abortEarly: true,
+      },
+    }),
+  ],
+  providers: [AppConfigService],
+  exports: [AppConfigService],
+})
+export class AppConfigModule {}

drips/src/config/config.service.ts

@@ -0,0 +1,55 @@
+import { Injectable } from '@nestjs/common';
+import { ConfigService as NestConfigService } from '@nestjs/config';
+
+@Injectable()
+export class AppConfigService {
+  constructor(private configService: NestConfigService) {}
+
+  get nodeEnv(): string {
+    return this.configService.get<string>('NODE_ENV')!;
+  }
+
+  get port(): number {
+    return this.configService.get<number>('PORT')!;
+  }
+
+  get databaseHost(): string {
+    return this.configService.get<string>('DATABASE_HOST')!;
+  }
+
+  get databasePort(): number {
+    return this.configService.get<number>('DATABASE_PORT')!;
+  }
+
+  get databaseUser(): string {
+    return this.configService.get<string>('DATABASE_USER')!;
+  }
+
+  get databasePassword(): string {
+    return this.configService.get<string>('DATABASE_PASSWORD')!;
+  }
+
+  get databaseName(): string {
+    return this.configService.get<string>('DATABASE_NAME')!;
+  }
+
+  get redisHost(): string {
+    return this.configService.get<string>('REDIS_HOST')!;
+  }
+
+  get redisPort(): number {
+    return this.configService.get<number>('REDIS_PORT')!;
+  }
+
+  get redisPassword(): string | undefined {
+    return this.configService.get<string>('REDIS_PASSWORD');
+  }
+
+  get redisDb(): number {
+    return this.configService.get<number>('REDIS_DB')!;
+  }
+
+  get(key: string): any {
+    return this.configService.get(key);
+  }
+}

drips/src/config/env.validation.ts

@@ -0,0 +1,17 @@
+import * as Joi from 'joi';
+
+export const envValidationSchema = Joi.object({
+  NODE_ENV: Joi.string()
+    .valid('development', 'production', 'test', 'provision')
+    .default('development'),
+  PORT: Joi.number().default(3000),
+  DATABASE_HOST: Joi.string().required(),
+  DATABASE_PORT: Joi.number().default(5432),
+  DATABASE_USER: Joi.string().required(),
+  DATABASE_PASSWORD: Joi.string().required(),
+  DATABASE_NAME: Joi.string().required(),
+  REDIS_HOST: Joi.string().default('localhost'),
+  REDIS_PORT: Joi.number().default(6379),
+  REDIS_PASSWORD: Joi.string().allow('').optional(),
+  REDIS_DB: Joi.number().default(0),
+});

drips/src/main.ts

@@ -1,6 +1,7 @@
 import { NestFactory } from '@nestjs/core';
 import { ValidationPipe } from '@nestjs/common';
 import { AppModule } from './app.module';
+import { AppConfigService } from './config/config.service';
 
 async function bootstrap() {
   const app = await NestFactory.create(AppModule);
@@ -14,8 +15,11 @@ async function bootstrap() {
     }),
   );
 
-  await app.listen(process.env.PORT ?? 3000, () => {
-    console.log(`Server running on http://localhost:${process.env.PORT ?? 3000}`);
+  const configService = app.get(AppConfigService);
+  const port = configService.port;
+
+  await app.listen(port, () => {
+    console.log(`Server running on http://localhost:${port}`);
   });
 }
 bootstrap();