Backend

• Using Express for server

Architecture

• We are using the controller-service-repository pattern

  • Controller: Where APIs are defined and exposed

  • Service: Business logic implementations, 3rd party integrations. Logic of fetching/filling up cache

  • Repository: Storage (database) retrieval

• Divide functionalities by course, reviews, reports, and users

  • Course: Getting & searching courses

  • Reviews: Getting & searching for reviews

  • Reports: Reports made by users on a review reporting inappropriate content

  • Users: Creates new users, update them, get their info, and verify their session

Users

• Uses csesoc’s authentication system

• The user class stores their reviews, bookmarks, admin status, and report logs

• We are using NextAuth to handle sign in and sign out functionalities

• validationMiddleware: Checks if the request has the correct structure based on the defined schema

• verifyToken: Making sure the user in session is correct by calling csesoc’s auth and matching the zid’s

• validateReq: Alternative to request (wrapper for fetch API calls) that takes in the user’s ID and token session along the request. Used where we care about user sessions

Redis

• In-memory data storage, cache

• Class in modules/redis.ts

• Stores data in key-value pairs

  • E.g. CourseID: Course Data

• Will get called first to fetch data. If there is a miss, the service will call the repository and then put the data in the cache

Prisma

• Object-Relational Mapper (ORM)

• Class in modules/prisma.ts

• When the server starts, it will create a Prisma manager that connects to our database

• The repositories will do the SQL queries through Prisma, which will interact with our database

• We define all the table schemas in Typescript so that Prisma understands the data