datasource-personalization-api-2.ts

export class PersonalizationAPI extends RESTDataSource {
  baseURL = 'https://personalization-api.example.com';

  willSendRequest(request: Request) {
    request.headers.set('Authorization', this.context.token);
  }

  private progressLoader = new DataLoader(async (ids: string[]) => {
    const progressList = await this.get('progress', {
      ids: ids.join(','),
    });
    return ids.map(id =>
      progressList.find((progress: any) => progress.id === id),
    );
  });

  async getProgressFor(id: string) {
    return this.progressLoader.load(id);
  }
}