The Repository pattern is widely used in software applications to separate the data access logic from the business logic. The main purpose of this project is to explore how the Repository pattern can be applied in Node.js projects.
As mentioned earlier, the Repository pattern is used to separate the data access logic from the business logic, and for that, we need a place where data access is performed.
Within the src folder, we have a folder called repositories, and inside it, we have our contracts and their respective repositories, but first, we need to understand what contracts are.
Contracts are nothing more than interfaces responsible for telling us which methods we need to implement in our repository, for example:
import { Prisma, User } from '@prisma/client';
export interface UsersRepository {
create(user: Prisma.UserCreateInput): Promise<User>;
}The above contract (located in src/repositories/interfaces) tells us that we need to implement the create method in our user repository, as well as informing us which data should be provided and returned.
The repository responsible for working with user data (located in src/repositories/prisma) will implement our contract and the logic for inserting data:
import { Prisma } from '@prisma/client';
import { prisma } from '../../libs';
import { UsersRepository } from '../interfaces';
export class PrismaUsersRepository implements UsersRepository {
async create(data: Prisma.UserCreateInput) {
const user = await prisma.user.create({ data });
return user;
}
}With the repository created, the logic responsible for inserting user data into our database is centralized in one place.
To use the repository, we create an instance of it and use its methods:
const prismaUsersRepository = new PrismaUsersRepository();
const user = await prismaUsersRepository.create({
bio: 'Developer since 2021.',
email: 'marcosjbotene@gmail.com',
name: 'Marcos Botene',
});