typescript - NestJS 使用 .env 和 @nestjs/config 设置 TypeOrm 连接

Question

我试图找到使用 .env 文件设置 NestJS 数据库的最合法方法。那就是我想用 @nestjs/config用于导入 .env 变量并在 TypeOrmModule 中使用它们的包。
看来我需要使用 TypeOrmModule.forRootAsync .
我正在尝试这样做:

// app.module.ts

@Module({
  imports: [
    ConfigModule.forRoot({
      isGlobal: true,
    }),
    TypeOrmModule.forRootAsync({
      useClass: TypeOrmConfigService,
    }),
    ...
  ],

})
export class AppModule {}

然后，还有 TypeOrmConfigService :

import { Module } from '@nestjs/common';
import { ConfigModule, ConfigService } from '@nestjs/config';
import { TypeOrmModuleOptions, TypeOrmOptionsFactory } from '@nestjs/typeorm';

@Module({
  imports: [ConfigModule],
})
export class TypeOrmConfigService implements TypeOrmOptionsFactory {
  constructor(private configService: ConfigService) {}

  createTypeOrmOptions(): TypeOrmModuleOptions {
    return {
      type: 'mysql',
      host: this.configService.get('DATABASE_HOST'),
      username: this.configService.get('DATABASE_USERNAME'),
      password: this.configService.get('DATABASE_PASSWORD'),
    };
  }
}

最后一个不正确: Nest can't resolve dependencies of the TypeOrmConfigService (?). Please make sure that the argument at index [0] is available in the TypeOrmCoreModule context.如何解决？
或者(最喜欢的)是否有 NestJs + TypeOrm + @nestjs/config + .env(在 repo 之外，带有 DATABASE_PASSWORD)+ config(我的意思是处理 config/development.yml、config/的 npm 包配置)的例子production.yml 等)？
似乎我正在寻找一个非常标准的东西，hello world，它应该是每个 NestJS 项目的开始，但我发现将 @nestjs/config 和 TypeOrm 结合起来很困难。
更新。如果我更换 @Module与 @Injectable ，错误完全一样:

yarn run v1.22.4
$ NODE_ENV=development nodemon
[nodemon] 1.19.0
[nodemon] to restart at any time, enter `rs`
[nodemon] watching: /home/kasheftin/work/pubngn4/nestjs-course-task-management/src/**/*
[nodemon] starting `ts-node -r tsconfig-paths/register src/main.ts`
[Nest] 25384   - 09/01/2020, 8:07 PM   [NestFactory] Starting Nest application...
[Nest] 25384   - 09/01/2020, 8:07 PM   [InstanceLoader] AppModule dependencies initialized +11ms
[Nest] 25384   - 09/01/2020, 8:07 PM   [InstanceLoader] TypeOrmModule dependencies initialized +0ms
[Nest] 25384   - 09/01/2020, 8:07 PM   [InstanceLoader] PassportModule dependencies initialized +0ms
[Nest] 25384   - 09/01/2020, 8:07 PM   [ExceptionHandler] Nest can't resolve dependencies of the TypeOrmConfigService (?). Please make sure that the argument at index [0] is available in the TypeOrmCoreModule context. +1ms
Error: Nest can't resolve dependencies of the TypeOrmConfigService (?). Please make sure that the argument at index [0] is available in the TypeOrmCoreModule context.
    at Injector.lookupComponentInExports (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:180:19)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
    at Injector.resolveComponentInstance (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:143:33)
    at resolveParam (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:96:38)
    at async Promise.all (index 0)
    at Injector.resolveConstructorParams (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:112:27)
    at Injector.loadInstance (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:78:9)
    at Injector.loadProvider (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/injector.js:35:9)
    at async Promise.all (index 3)
    at InstanceLoader.createInstancesOfProviders (/home/kasheftin/work/pubngn4/nestjs-course-task-management/node_modules/@nestjs/core/injector/instance-loader.js:41:9)
 1: 0xa2afd0 node::Abort() [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
 2: 0xa9e7a9  [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
 3: 0xc06bab  [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
 4: 0xc08156  [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
 5: 0xc087d6 v8::internal::Builtin_HandleApiCall(int, unsigned long*, v8::internal::Isolate*) [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
 6: 0x13a9f19  [/home/kasheftin/.nvm/versions/node/v14.3.0/bin/node]
Aborted (core dumped)
[nodemon] app crashed - waiting for file changes before starting...

Answer 1

这是我在 app.module.ts 中使用 Postgres 的工作脚本，但对于 MySQL 将非常相似。有时在重建之前需要手动删除 dist 文件夹 - 当 DB 无法同步时。

import { ConfigModule, ConfigService } from '@nestjs/config';


@Module({
  imports: [
    ConfigModule.forRoot(),
    TypeOrmModule.forRootAsync({
      imports: [ConfigModule],      
      useFactory: (configService: ConfigService) => ({
        type: 'postgres' as 'postgres',
        host: configService.get<string>('DATABASE_HOST'),
        port: parseInt(configService.get<string>('DATABASE_PORT')),
        username: configService.get<string>('DATABASE_USER'),
        password: configService.get<string>('DATABASE_PASS'),
        database: configService.get<string>('DATABASE_NAME'),
        entities: [__dirname + '/**/*.entity{.ts,.js}'],
        synchronize: true,
      }),
      inject: [ConfigService],
    }),

.env 在根文件夹中

DATABASE_USER=
DATABASE_PASS=
DATABASE_HOST=
DATABASE_NAME=
DATABASE_PORT=