DRY - Updated ProductService

ProductService.ts

class ProductService {
    private db: DB<Product>;
    private entity = 'product';

    constructor() {
        this.db = new DB<Product>(this.entity);
    }
    
    async create(user: User, product: Product): Promise<Product | undefined> {
        if (userIsPermitted(user)) {
            console.log(`Create ${this.entity}.`);
            return this.db.create({user, product});
        }
        return undefined;
    }

    async read(user: User, product: Product): Promise<Product | undefined> {
        console.log(`Get ${this.entity}`);
        return this.db.read({user, product});
    }

    async update(user: User, product: Product): Promise<Product | undefined> {
        if (userIsPermitted(user)) {
            console.log(`Update ${this.entity}.`);
            return this.db.update({user, product});
        }
        return undefined;
    }

    async delete(user: User, product: Product): Promise<Product | undefined> {
        if (userIsPermitted(user)) {
            console.log(`Delete ${this.entity}.`);
            return this.db.delete({user, product});
        }
        return undefined;
    }
}