Implement Database component

[Keith-CY]

Please add more info on how to implement the storage component in this issue, e.g. tech stack, schedule, and the PR of adding the database component could be referenced here.

Ref:

• Architecture design of Kuai runtime #7
• Design of Database component of Kuai runtime #16

[felicityin]

• tech stack: inversify, typeorm

• schedule:

  • research & design: 11.21 - 11.24
  • implement: 11.24 - 12.01
  • test: 12.01 - 12.05

• usage

  • inject typeorm
    user.service.ts:

    import { DataSource, EntityManager, Repository } from 'typeorm';
    import { InjectDataSource, InjectRepository, InjectEntityManager, Service } from 'my-lib';
    import { User } from './user.entity';
    
    @Service()
    export class UserService {
      @InjectDataSource()
      private dataSource!: DataSource;
    
      @InjectEntityManager()
      private entityManager!: EntityManager;
    
      constructor(@InjectRepository(User) private repository: Repository<User>) {}
    
      savebyRepository(post: User) {
        return this.repository.save(post);
      }
    
      saveByManager(post: User) {
        return this.entityManager.save(post);
      }
    
      async saveManyByTransaction(users: User[]) {
        const queryRunner = this.dataSource.createQueryRunner();
      
        await queryRunner.connect();
        await queryRunner.startTransaction();
        try {
          for (const user of users) {
            await queryRunner.manager.save(user);
          }
      
          await queryRunner.commitTransaction();
        } catch (err) {
          await queryRunner.rollbackTransaction();
        } finally {
          await queryRunner.release();
        }
      }
    
      findAll() {
        return this.repository.find();
      }
    }
    

  • use case
    app.ts:

    import { DataSourceOptions } from 'typeorm';
    import { container, TypeOrmManager } from 'my-lib';
    import { UserService } from './user.service';
    import { User } from './user.entity';
    
    export async function startApp() {
      const options: DataSourceOptions = {
        type: "postgres",
        host: "localhost",
        port: 5432,
        username: "test",
        password: "test",
        database: "test",
        synchronize: true,
        logging: false,
        entities: [User],
        migrations: [],
        subscribers: [],
      };
      await TypeOrmManager.importRoot(options);
      await TypeOrmManager.importRepository(options, [User]);
    
      const userOne = new User();
      userOne.id = 1;
      userOne.name = 'Alice';
    
      const userTwo = new User();
      userTwo.id = 2;
      userTwo.name = `Bob`;
    
      const service = container.get<UserService>(UserService.name);
    
      await service.savebyRepository(userOne);
      await service.saveByManager(userTwo);
    
      const userThree = new User();
      userThree.id = 3;
      userThree.name = `Olivia`;
    
      const userFour = new User();
      userFour.id = 4;
      userFour.name = `Ada`;
      await service.saveManyByTransaction([userThree, userFour]);
    
      const userList = await service.findAll();
      console.log({ userList });
    
      const conn = await TypeOrmManager.getDataSource(options);
      conn.destroy();
    }
    

[felicityin]

PR: #56