RPG-SHOP

A (WIP) RESTful API and CLI client for an RPG shop inventory system, built with Go and PostgreSQL. The API handles all the business logic and database operations. The CLI client provides a terminal interface for browsing and purchasing items.

Tech Stack

• Go: HTTP server and CLI client
• PostgreSQL: persistent storage
• goose: database migrations
• sqlc: type-safe SQL query generation

Features

• Browse shop inventory with item names, prices, and current quantity
• Buy items by index number (stock decreases on purchase, fails if out of stock)
• Restock items by index with a specified quantity
• Full REST API with JSON responses
• Register and log in with a name and password
• Password hashing using argon2id

Project Structure:

rpg-shop/
├── main.go               # Server entry point
├── server.go             # Server struct and helpers
├── handler_items.go      # HTTP handlers
├── items.go              # Item type definition
├── cmd/
│   └── shop/
│       └── main.go       # CLI client entry point
├── internal/
│   └── auth/             # user authentication stuff
│   └── database/         # sqlc generated code
├── sql/
│   ├── queries/          # SQL queries
│   └── schema/           # goose migrations
└── sqlc.yaml

Prerequisites

• Go 1.21+
• PostgreSQL
• goose: go install github.com/pressly/goose/v3/cmd/goose@latest
• sqlc: go install github.com/sqlc-dev/sqlc/cmd/sqlc@latest

Setup

1. Clone the repository

git clone https://github.com/LunarDrift/rpg-shop
cd rpg-shop

2. Create the database

createdb rpg_shop

3. Run migrations

goose -dir sql/schema postgres "postgres://username:password@localhost/rpg_shop?sslmode=disable" up

4. Seed the database

psql rpg_shop < sql/seed.sql

5. Set up the environment variables

   • Copy and rename the .env.example file to .env and enter your database name:

   cp .env.example .env

   # Generate a secure JWT secret
   openssl rand -hex 64

   # If your Postgres user has a password:
   DB_URL=postgres://username:password@localhost/rpg_shop?sslmode=disable
   
   # If no password required:
   DB_URL=postgres://localhost/rpg_shop?sslmode=disable
   
   JWT_TOKEN=your_jwt_secret

6. Install dependencies

go mod tidy

Running the Server

go run .

The server starts on http://localhost:8080

Using the CLI

In a separate terminal:

# Browse all items in the shop
go run ./cmd/shop browse

# Register a new user (starts with 500g)
go run ./cmd/shop register <name> <password>

# Log in
go run ./cmd/shop login <name> <password>

# Buy an item by its index number and optional quantity
go run ./cmd/shop buy 2 5

# Show the current user and balance
go run ./cmd/shop whoami

# Explore and gain money
go run ./cmd/shop explore

# Restock an item (shopkeeper/admin)
go run ./cmd/shop/restock 2 10

# Log out
go run ./cmd/shop logout

API Endpoints

Method	Endpoint	Description
GET	/health	Health check
GET	/items	List all items
GET	/items/{id}	Get item by ID
POST	/items	Create a new item (requires admin privelages)
POST	/items/buy/{id}	Buy an item
PATCH	/items/restock/{id}	Restock an item (requires admin privelages)
DELETE	/items/{id}	Delete an item (requires admin privelages)
POST	/users	Register a new user
POST	/users/login	Log in to a registered user with name and password
GET	/users	Get a user by name or list all users if no name provided
GET	/users/{id}	Get a user by ID
PATCH	users/earn	Gain a random amount (10-100) of gold

Seeding the Database

To add items directly via psql:

psql rpg_shop

INSERT INTO items (name, description, price, quantity)
VALUES
  ('Iron Sword', 'A sturdy blade forged from iron', 100, 5),
  ('Health Potion', 'Restores 50 HP', 25, 10),
  ('Magic Staff', 'Channels arcane energy', 200, 2);