patterns

[TYPESCRIPT] 타입스크립트 디자인 패턴 - Facade

Facade Pattern

The façade pattern is one of the structural software design patterns.

Structural: 객체간의 관계를 처리

이점

  1. 여러시스템을 통합하는 인터페이스가 필요한 경우 사용.

서브시스템1

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// subsystem1.ts
export class Contract {
  private contractTerminationDateexport class Contract {
  private contractTerminationDate: Date;
  constructor(terminationDate: Date) {
    this.contractTerminationDate = terminationDate;
  }
  checkActiveContract(date: Date): boolean {
    if (date < this.contractTerminationDate) {
      return true;
    } else {
      return false;
    }
  }
}

서브시스템2

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// subsystem2.ts
export class TeamFunds {
  private totalFunds: number;
  constructor(total: number) {
    this.totalFunds = total;
  }
  checkFunds(transferFee: number): boolean {
    if (transferFee < this.totalFunds) {
      return true;
    } else {
      return false;
    }
  }
}

Facade 패턴으로 2개의 서브 시스템을 통합하여 기능제공

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// facade.ts
import { Contract } from './subsystem1';
import { TeamFunds } from './subsystem2';
 
export class Facade {
  private contract: Contract = new Contract(new Date(new Date().setDate(new Date().getDate() + 10)));
  private funds: TeamFunds = new TeamFunds(200000);
 
  private playerContract: Date;
  private playerPrice: number;
 
  constructor(playerPrice: number) {
    this.playerContract = new Date();
    this.playerPrice = playerPrice;
  }
 
  buyPlayer(): void {
    if (this.contract.checkActiveContract(this.playerContract)) {
      console.log('Player has active contract');
    } else {
      console.log('Player has no active contract');
      if (!this.funds.checkFunds(this.playerPrice)) {
        console.log('Player is too expensive to buy.');
      } else {
        console.log('Player can be bought.');
      }
    }
  }
}

사용시

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// app.ts
import { Facade } from './facade';
 
const facade: Facade = new Facade(200001);
facade.buyPlayer();