LibreMatch Backend

Some things may be out of scope, we can still collect them here, to have an overview and include some of them in the design process.

User stands for the user of the LibreMatch API.

We will need a running instance of a Steam Client for each game. To circumvent limitations (as only holding one login to steam per account on a certain moment in time is needed) we use a proxy to forward our requests on behalf of a certain session.

Usage

Base URL: https://rlink.api.tools.uber.space/relic

You need to get an API_KEY for the proxy from the team members.

Then you can make calls to the proxy e.g. for endpoint `/game/news/getNews` call:

https://proxy.api.tools.uber.space/relic/game/news/getNews

You need to supply a header with the API_KEY e.g.

API_KEY=...

All query parameters that you add to the request will be forwarded to the Relic Link API on your behalf.

Insomnia is a API design platform.

Bright Sky pulls weather data from DWD and implements a JSON-API on top of it for its users. Their architecture looks like on the image on the right side. It's some kind of the same what we also want to achieve.

This is taken from the Official repository :

• The brightsky worker, which leverages the logic contained in the brightsky Python package to retrieve weather records from the DWD server, parse them, and store them in a database. It will periodically poll the DWD servers for new data.
• The brightsky webserver (API), which serves as gate to our database and processes all queries for weather records coming from the outside world.
• A PostgreSQL database consisting of two relevant tables:
  • sources contains information on the locations for which we hold weather records, and
  • weather contains the history of actual meteorological measurements (or forecasts) for these locations.
• A Redis server, which is used as the backend of the worker's task queue.

Basically we should poll the Relic Link API endpoints for all data every so many seconds (this time is our minimum latency for our whole system). So the time frame in which we see certain information (Match infos, wins of games) and could deliver information to our API.

Then we parse the results into a data structure of ourselves to make error handling easier and also deal with types of data and not handle everything as a huge JSON-Array that is being exposed by the Relic Link API. This data we send to the database which is our persistence layer. From our persistence layer we are able to request data for our endpoints that we expose to the users. Some endpoints may require a Pub/Sub API (e.g. live updates for match information), some are fine with the usual REST-API approach.

There are a few available data sources (resource) we can query our data from.

• Authenticated endpoints
  Requests to these endpoints should be rather limited and only for really essential things.
  Most of our data we should get from the /community-Endpoints.

• Community endpoints
  Data here is relatively scarce, though most of our data we should fetch from here.

see Libre:Match Proxy

Intermediate Cache

TODO: Create an overview over all data we can get from the RelicLink API.

First step: Version control our database schema with a lightweight, framework-agnostic database migration tool

To visualise long-running requests and loads we should use some statistics extension for Postgres.

Sometimes resources will need authorisation to be accessed by privileged community members. Such members could be tournament organizers and admins that want to setup a schedule within the backend to delay the access to certain player information for a limited amount of time. This could be needed during tournaments, so people aren't able to find out results of matches before they are officially concluded (e.g. in case of casting recorded games) and spoil other people with the results.

The Relic Link ID aka RLINK_ID is a unique identifier for every player on the Relic Link platform, no matter if the person bought a game on Steam or Microsoft Store. Authentication for a player on that platform could be achieved by utilising web browser based authentication with Steam OpenID .

OpenAPI

To make it easy to start using our API we should provide an OpenAPI file so that the users are able to generate clients for our API for their favourite programming language. An OpenAPI file also works well as a complete documentation of the API. There are several Tools that make dealing with an OpenAPI a breeze.

TODO: Generating OpenAPI files from within axum is in the making.

Some information for players might want to be constantly queried by the users of our API, for example match information. These information we should supply via an endpoint that can be subscribed to and communicates via a Websocket.