• • 错误**迁移生成错误：MissingDriverError：错误的司机："undefined"给出。支持的驱动程序有："aurora-data-api"，"aurora-data-api-pg"，"better-sqlite3"，"capacitor"，"cockroachdb"，"cordova"，"expo"，"mariadb"，"mongodb"，"mssql"，"mysql"，"nativescript"，"oracle"，"postgres"，"react-native"，"sap"，"sqlite"，"sqljs". at MissingDriverError. TypeORMError [as constructor]（D：\Projects\Mark1\api2\src\error\TypeORMError.ts：7：9）在新MissingDriverError（D：\Projects\Mark1\api2\src\error\MissingDriverError.ts：8：9）at DriverFactory. create（D：\Projects\Mark1\api2\src\driver\DriverFactory.ts：七十：23）在新连接（D：\Projects\Mark1\api2\src\connection\Connection.ts：一百二十二：43）在ConnectionManager. create（D：\Projects\Mark1\api2\src\connection\ConnectionManager.ts：六十一：28）在D：\Projects\Mark1\api2\src\globals.ts：七十七：35在步骤（D：\Projects\Mark1\api2\node_modules\tslib\tslib.js：一百四十三：27）在 www.example.com (D:\Projects\Mark1\api2\node_modules\tslib\tslib.js:124:57) at D:\Projects\Mark1\api2\node_modules\tslib\tslib.js:117:75 at new Promise ()
• • ormConfig. ts**

import { TypeOrmModuleOptions } from '@nestjs/typeorm';
import { join } from 'path';

require('dotenv').config();

class ConfigService {

  constructor(private env: { [k: string]: string | undefined }) { }

  private getValue(key: string, throwOnMissing = true): string {
    const value = this.env[key];
    if (!value && throwOnMissing) {
      throw new Error(`config error - missing env.${key}`);
    }

    return value;
  }

  public ensureValues(keys: string[]) {
    keys.forEach(k => this.getValue(k, true));
    return this;
  }

  public getPort() {
    return this.getValue('PORT', true);
  }

  public isProduction() {
    const mode = this.getValue('MODE', false);
    return mode != 'DEV';
  }

  public getTypeOrmConfig(): TypeOrmModuleOptions {
    return {
      type: 'postgres',
      host: this.getValue('POSTGRES_HOST'),
      port: parseInt(this.getValue('POSTGRES_PORT')),
      username: this.getValue('POSTGRES_USER'),
      password: this.getValue('POSTGRES_PASSWORD'),
      database: this.getValue('POSTGRES_DATABASE'),
      entities: [join(__dirname, '**', '*.entity.{ts,js}')],
      migrationsTableName: 'migration',
      migrations: ['src/migration/*.ts'],
      cli: {
        migrationsDir: 'src/migration',
      },
    };
  }

}

const configService = new ConfigService(process.env)
  .ensureValues([
    'POSTGRES_HOST',
    'POSTGRES_PORT',
    'POSTGRES_USER',
    'POSTGRES_PASSWORD',
    'POSTGRES_DATABASE'
  ]);

export = configService ;

• • appmodule. ts**

import { Module } from '@nestjs/common';
import { TypeOrmModule } from '@nestjs/typeorm';
import configService from 'ormConfig';
import { AppController } from './app.controller';
import { AppService } from './app.service';

@Module({
  imports: [TypeOrmModule.forRoot(configService.getTypeOrmConfig())],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {

}

• . env文件*

POSTGRES_HOST=localhost
POSTGRES_PORT=8080
POSTGRES_USER=postgres
POSTGRES_PASSWORD=saad2113
POSTGRES_DATABASE=mark1
PORT=3000
MODE=DEV
RUN_MIGRATIONS=true