Dota Showcase - Inventory Service

REST API service to store and track changes of steam user's dota 2 inventory items.

Features

• Inventory history - created, updated, deleted items
• Rate limiter
• Unit tests

API Docs

Swagger OpenAPI 3 is available by path:

• UI: host:port/swagger-ui.html
• JSON: host:port/api-docs

Inventory Endpoints

• Show Inventories: GET /api/v1/inventories/
• Create an Inventory (load items from steam): POST /api/v1/inventories/:steamid/
• Show an Inventory: GET /api/v1/inventories/:steamid/
• Update an Inventory (reload items from steam): PUT /api/v1/inventories/:steamid/
• Delete an Inventory: DELETE /api/v1/inventories/:steamid/

Inventory Items Endpoints

• Show Inventory Items: GET /api/v1/inventories/:steamid/items/
• Show Inventory Items (pagination): GET /api/v1/inventories/:steamid/items/page/
• Show Inventory Items changes: GET /api/v1/inventories/:steamid/changes/
• Show Inventory Items changes (for a version): GET /api/v1/inventories/:steamid/changes/:version/

Getting Started

Prerequisites

• Java 17
• Apache Maven
• MongoDB 5.0

Installation

1. Create .env based on .env.example
2. Create environment.properties based on environment.properties.example in app/src/main/resources
3. Set the steam api key property to access Steam's API:

   env.steam.api.key=your_api_key

4. To run in development environment. You can use a default build for IntelliJ IDEA to run the app - .run/dev-build.run.xml.

   docker-compose up

5. To run in production environment

   docker compose -f docker-compose.prod.yml up -d

Data Model

Conceptual entity relation diagram (Barker's system):

Back-of-the-envelope Estimations

Storage Space

Assumptions:

• Average inventory item size - 500 bytes.
• Average user has 7000 inventory items.
• Users update inventory once per day. Each day it increased by some small coefficient (0.05).
• Data is stored for a year.

Estimate:

• User inventory size: 500 * 7000 = 3.5 MB
• User inventory size for a year: 3.5 MB + (365 * 0.05 * 3.5) = ~70 MB
• Storage for 100K users: 70MB * 1000000 = 7 GB

Resources

• Steam API - GetPlayerItems

License

The GNU General Public License v3.0. Please see License File for more information.