Backend System Design

[samuraikun]

Introduction

• The issue is written as a Design Document.

Design Document Based on https://www.industrialempathy.com/posts/design-docs-at-google/

Scope

Scope of this design document

• The design only includes backend API & Infrastructure

Background

Background: Why does this document write?

• The main purpose is to share knowledge about backend system design and context.

Required

• Start for free

Proposal

What kind of design will you choose? Also, write logically why you have chosen that option.

Language: TypeScript

Reason

• Everyone has enough experience with TypeScript.
• Type system helps us to collaborate effectively with each other

Database: PostgreSQL(Supabase)

• https://supabase.com/docs/guides/database/overview

Reason

• Start for free
• Able to create tables from GUI
• Support for Row Level Security
  • https://supabase.com/docs/guides/database/postgres/row-level-security
• Familiar with Prisma
  • https://supabase.com/partners/integrations/prisma

Database Architecture

• https://github.com/tabi-memo/backend/issues/5

Auth

• https://github.com/tabi-memo/backend/issues/4

GraphQL API

• https://github.com/tabi-memo/backend/issues/3

※ Full-scratch approach

Framework: Nest.js

• https://nestjs.com/
• https://awstip.com/understanding-nestjs-architecture-f257d054211d

GraphQL middleware:

These are described nest.js document. https://docs.nestjs.com/graphql/quick-start#installation

• @nestjs/graphql
• @nestjs/apollo
• @apollo/server
• graphql

Test tool: @nestjs/testing

• https://docs.nestjs.com/fundamentals/testing

ORM: Prisma

• https://github.com/prisma/prisma

Reason

• Implemented TypeScript
• More simple interface than TypeORM
• Most popular
  • https://npmtrends.com/prisma-vs-sequelize-vs-typeorm

Validation: zod

• https://zod.dev/

Reason

• Type-safe
• Understandable validation API
• Easy handling error message

Storage: Subase Storage

• https://supabase.com/docs/guides/storage

Reason

• Start for free
• Integrate easily Supabase Database
• Support for CDN
• Storage API is implemented by TypeScript

CI/CD

• GitHub Actions

Reason

• Start for free
• Run Job(lint, test, deploy, etc)
• Integrate another frontend repository
  • ex. Sync GraphQL Schema file

[Yo-mah-Ya]

Seems to be great overall, but I'd like to add some comments below.

Framework: Nest.js

No suggestion or preferable but just simple question: As long as I google GraphQL servers, Apollo server is also popular and reliable. And I've used this before. And Nest.js seems to use it within it. It might be useful and simplified, but when some problems happens, it's going to be more difficult to fix it, for sure. What do you think about the pros and cons of them ?

Authentication/Authorization: Supabase

Want some explicit comments where and how exactly we store user password just in case. And token as well.

Server (WIP)

First of all, Cloud Run looks nice ! But I'd say it's not going to be the reason that we'll choose it as a server with above investigation.

Somewhat it looks docker is considered that important though, is it really necessary in this project first of all? From where I sit, it'd be rather inconvenient when we can prepare particular environment, which are like exact version of nodejs run time, OS and whatnot. My concern is building time of container image and how we manage.

And AWS says it officially supports Docker with Lambda

Database Architecture (WIP)

• naming rule From where I sit, in general, snake case seems to be preferable in RDB context instead of camel case.

• overall What is uuid for in each table? Is id as PK used internal system, and uuid for external, as in API (GraphQL id ?), something like that ?

• Users => After I figure out where and how exactly we handle with password, just wanna clarify

• Profiles Do we actually need this table ? Can you give me some use case ?

• Invitations How we handle with permissionLevel.. yes nice, and how we regulate.

• TripFiles I'm wondering if we could allow users to add more than 1 images to every trip. As long as I see UI wireframe, it'd be enough 1.

[samuraikun]

@Yo-mah-Ya This issue is too huge💦 So, I divided it into several like below.

• https://github.com/tabi-memo/backend/issues/3
• https://github.com/tabi-memo/backend/issues/4
• https://github.com/tabi-memo/backend/issues/5