NestJS API Project

Monorepo-style project currently focused on one backend app (api/) built with NestJS + Prisma + PostgreSQL.

Project scope

• Root: project docs and repository metadata
• App: api/ (NestJS API)
• Current domain: users (CRUD + permission checks in use cases)

Architecture

The API is organized by layers inside api/src/modules/.:

1. Domain: entities/value objects + repository contracts
2. Application: use cases (business rules)
3. Infrastructure: Prisma repository implementation
4. Presentation: HTTP controller + DTOs
5. Shared: database and crypto services/modules

Flow:

HTTP Controller -> Use Case -> Repository Abstraction -> Prisma Repository -> PostgreSQL

Main structure

NestJS_API_Project/
|-- README.md
`-- api/
    |-- package.json
    |-- prisma.config.ts
    |-- prisma/
    |   |-- schema.prisma
    |   `-- migrations/
    `-- src/
        |-- main.ts
        |-- app.module.ts
        |-- modules/./
        |   |-- module.ts
        |   |-- presenters/http/.http.ts
        |   |-- presenters/dtos/.dto.ts
        |   |-- application/use-cases/.use-case.ts
        |   |-- domain/entities/.entity.ts
        |   |-- domain/repositories/.repository.ts
        |   `-- infrastructure/repositories/prisma.repository.ts
        `-- shared/
            |-- database/prisma.service.ts
            `-- infrastructure/crypto/hash.service.ts

Tech stack

• NestJS 11 (Express platform)
• Prisma 7 (@prisma/client, @prisma/adapter-pg)
• PostgreSQL
• Swagger (/api)
• class-validator + class-transformer
• Argon2 (password hashing with pepper)
• Jest + ESLint + Prettier

Setup and run

From repository root:

cd api
npm install
npx prisma migrate dev
npx prisma generate
npm run start:dev

Default URLs:

• API: http://localhost:3000
• Swagger: http://localhost:3000/api

Environment variables (api/.env)

DATABASE_URL=postgresql://postgres:postgres@localhost:5432/postgres
PEPPER=local-development-pepper

Variable	Required	Default fallback	Purpose
DATABASE_URL	No	postgresql://postgres:postgres@localhost:5432/postgres	PostgreSQL connection string
PEPPER	No	local-development-pepper	Extra secret added before hashing passwords

If missing, the app uses fallbacks and logs warnings.

Database models

Users

Role enum:

• USER
• ADMIN

users table:

Column	Type	Notes
id	TEXT	Primary key (UUID)
name	TEXT NULL	Optional
email	TEXT	Unique
password	TEXT NULL	Optional
googleId	TEXT NULL	Unique, optional
role	Role	Default USER
createdAt	TIMESTAMP(3)	Default now
updatedAt	TIMESTAMP(3)	Auto-updated

API reference

Base path: /users

Method	Endpoint	Description	Body	Success
POST	/users/create	Create user	email, password, name?	201
GET	/users/getAll	List users	-	200
GET	/users/get/:id	Get user by ID	-	200
PUT	/users/update/:id	Update user	email?, password?, name?	200
DELETE	/users/delete/:id	Delete user	-	204

Validation and rules

• Email must be valid
• Password must be at least 12 chars and include uppercase, lowercase, number, and special character
• Email uniqueness is enforced in create/update use cases
• IDs are generated as UUIDs
• Permission rule for update/delete:
  • requester is ADMIN, or
  • requester is the target user

Scripts (api/)

Command	Purpose
npm run start:dev	Run in watch mode
npm run build	Build project
npm run start:prod	Run compiled app
npm run lint	Run ESLint (--fix)
npm run test	Unit tests
npm run test:e2e	E2E tests

Author

jpedropraf