使用AWS参数存储的NestJs TypeORM配置

Question

NestJS的新手，遇到了一个问题。对于我们的部署，我们需要从AWS Parameter Store（Systems Manager）获取配置，包括数据库连接字符串。我有一个配置模块和配置服务，它基于参数存储路径检索我的环境的所有参数存储项：

这是我的配置服务：

import * as dotenv from 'dotenv';
import * as fs from 'fs';
import * as AWS from 'aws-sdk';

export class ConfigService {
    private readonly envConfig: { [key: string]: string };
    private awsParamStoreEntries: { [key: string]: string }[];

    constructor(awsParamStorePath: string, filePath: string) {
        this.envConfig = dotenv.parse(fs.readFileSync(filePath));

        this.loadAwsParameterStoreEntries(awsParamStorePath).then((data) => {
            this.awsParamStoreEntries = data;
        });
    }

    loadAwsParameterStoreEntries(pathPrefix: string) {
        const credentials = new AWS.SharedIniFileCredentials({ profile: 'grasshopper-parameter' });
        AWS.config.credentials = credentials;
        const ssm = new AWS.SSM({ region: 'us-west-2' });
        var params: { [key: string]: string }[] = [];

        return getParams({
            Path: '/app/v3/development/',
            Recursive: true,
            WithDecryption: true,
            MaxResults: 10,
        }).then(() => {
            return params;
        });

        function getParams(options) {
            return new Promise((resolve, reject) => {
                ssm.getParametersByPath(options, processParams(options, (err, data) => {
                    if (err) {
                        return reject(err);
                    }
                    resolve(data);
                }));
            });
        }

        function processParams(options, cb) {
            return function (err, data) {
                if (err) {
                    return cb(err)
                };
                data.Parameters.forEach(element => {
                    let key = element.Name.split('/').join(':')
                    params.push({ key: key, value: element.Value });
                });
                if (data.NextToken) {
                    const nextOptions = Object.assign({}, options);
                    nextOptions.NextToken = data.NextToken;
                    return ssm.getParametersByPath(nextOptions, processParams(options, cb));
                }
                return cb(null);
            };
        }
    }

    get(key: string): string {
        return this.envConfig[key];
    }

    getParamStoreValue(key: string): string {
        return this.awsParamStoreEntries.find(element => element.key === key)['value'];
    }

    getDatabase(): string {
        return this.awsParamStoreEntries.find(element => element.key === 'ConnectionStrings:CoreDb')['value'];
    }
}

下面是主要的应用模块声明块：

@Module({
  imports: [ConfigModule, TypeOrmModule.forRootAsync({
    imports: [ConfigModule],
    useFactory: async (configService: ConfigService) => ({
      url: configService.getDatabase()
    }),
    inject: [ConfigService]
  }),
    CoreModule, AuthModule],
  controllers: [AppController],
  providers: [AppService],
})

如您所见，我正在告诉TypeForm在ConfigService中调用getDatabase（）方法，但问题是加载参数存储条目需要3-4秒，因此出现“未定义”错误，因为TypeForm尝试加载连接字符串时“this.awsParamStoreEntries”仍然未定义。

我在网上搜索了一下，看看是否已经这样做了，但是找不到任何以这种方式使用NestJS/TypeORM/AWS参数存储的东西。这里还有一个关于StackOverflow的现有（未回答）问题。

谢谢！

Answer 1

我们可以使用异步提供者。

将AWS SSM param store参数与NestJS配置服务一起使用的工作项目示例：

创建异步提供程序：

import * as AWS from 'aws-sdk';
import { Parameter } from 'aws-sdk/clients/ssm';

export const ssmProvider = {
  provide: 'AWS_SSM',
  useFactory: async (): Promise<Parameter[]> => {
    const ssmClient = new AWS.SSM({
      endpoint: 'endpoint',
      region: 'us-west-2',
    });
    const result = await ssmClient
      .getParametersByPath({
        Path: '/ssm/path',
        Recursive: true,
      })
      .promise();
    return result?.Parameters;
  },
};

然后，我们可以使用该提供程序来注入值。

例如，在配置服务中注入AWS SSM参数：

export class ConfigModule {
  static register(options: ConfigModuleOptions): DynamicModule {
    return {
      global: true,
      module: ConfigModule,
      providers: [
        ssmProvider,
        {
          provide: CONFIG_OPTIONS,
          useValue: options,
        },
        ConfigService,
      ],
      exports: [ConfigService],
    };
  }
}

在配置服务构造函数中：

constructor(
    @Inject(CONFIG_OPTIONS) options: ConfigOptions,
    @Inject('AWS_SSM') awsParameters: Parameter[],
  ) {}

编辑：NPM软件包，它提供在应用程序启动时加载aws参数store参数的服务：

参数-store服务

Answer 2

你能这样做吗。

import { TypeOrmOptionsFactory, TypeOrmModuleOptions } from '@nestjs/typeorm';
import { ConfigService } from './config.service';
import { Injectable } from '@nestjs/common';

@Injectable()
export class TypeOrmConfigService implements TypeOrmOptionsFactory {
    constructor(private readonly configService: ConfigService) {
    }

    async createTypeOrmOptions(): Promise<TypeOrmModuleOptions> {
        this.configService.awsParamStoreEntries = await this.configService.loadAwsParameterStoreEntries(this.configService.awsParamStorePath);

        return {
            url: this.configService.getDatabase(),
        };
    }
}

@Module({
  imports: [
    ConfigModule, 
    TypeOrmModule.forRootAsync({
      imports: [ConfigModule],
      useClass: TypeOrmConfigService,
    }),
    CoreModule, 
    AuthModule
  ],
  controllers: [AppController],
  providers: [AppService],
})

import * as dotenv from 'dotenv';
import * as fs from 'fs';
import * as AWS from 'aws-sdk';
import { Injectable } from '@nestjs/common';

@Injectable()
export class ConfigService {
    private readonly envConfig: { [key: string]: string };
    awsParamStoreEntries: { [key: string]: string }[];
    private readonly awsParamStorePath: string;

    constructor(awsParamStorePath: string, filePath: string) {
        this.envConfig = dotenv.parse(fs.readFileSync(filePath));
        this.awsParamStorePath = awsParamStorePath;
    }

    loadAwsParameterStoreEntries(pathPrefix: string) {...

https://docs.nestjs.com/techniques/database