Nest.js环境变量配置与序列化详解

yarn add dotenv-flow
yarn add @types/dotenv-flow -D

import * as dotenv from 'dotenv-flow'

/**
 * 导入 .env 环境
 * https://www.npmjs.com/package/dotenv-flow
 */
dotenv.config()

yarn add @nestjs/config

import { Module } from '@nestjs/common'
import { ConfigModule } from '@nestjs/config'

@Module({
 imports: [ConfigModule.forRoot()]
})
export class AppModule {}

DATABASE_USER=
DATABASE_PASSWORD=
DATABASE_NAME=
DATABASE_PORT=
DATABASE_HOST=

ConfigModule.forRoot({
 envFilePath: ['.env.development.local', '.env.development'],
})

export DATABASE_USER=root && nest start

export default () => ({
 port: parseInt(process.env.PORT, 10) || 3000,
 database: {
  host: process.env.DATABASE_HOST || 'localhost',
  port: parseInt(process.env.DATABASE_PORT, 10) || 3306
 }
})

import configuration from './config/configuration'

@Module({
 imports: [
  ConfigModule.forRoot({
   load: [configuration]
  })
 ]
})
export class AppModule {}

@Module({
 imports: [ConfigModule],
 // ...
})

import configuration from './config/configuration'

@Module({
 imports: [
  ConfigModule.forRoot({
   isGlobal: true,
   load: [configuration]
  })
 ]
})
export class AppModule {}

import { ConfigService } from '@nestjs/config'

constructor(private configService: ConfigService) {}

const dbUser = this.configService.get<string>('DATABASE_USER')
const dbHost = this.configService.get<string>('database.host')

yarn add class-transformer

import { Exclude } from 'class-transformer'

export class UserEntity {
 id: number
 firstName: string;
 lastName: string;

 @Exclude()
 password: string;

 constructor(partial: Partial<UserEntity>) {
  Object.assign(this, partial);
 }
}

@UseInterceptors(ClassSerializerInterceptor)
@Get(':id')
findOne(@Param('id') id: string): Promise<UserEntity> {
 return this.userService.findOne(id)
}