freedomfaighter / java-signature-generator

A sample OAuth2 Client Credentials flow application using Blizzard Battle.net APIs in Java.

Signature Generator (Java Sample Project)

Provided as a sample implementation of the OAuth2 Client Credentials flow, using the Blizzard Battle.net APIs for data.

Creates a web service that generates an image based on a World of Warcraft character profile on demand.

Setup

Requirements

• Java 8+
• Maven

Environment variables

As we don't wish to commit our secrets into this repository, this project requires a few environment variables set in order to successfully execute, much like you would expect to see in various hosting services. We do not recommend committing your secrets in your project's code repository either.

Variable Name	Variable Usage
BLIZZARD_CLIENT_ID	The Client ID from https://develop.battle.net/access for your project
BLIZZARD_CLIENT_SECRET	The Client Secret from https://develop.battle.net/access for your project

For local development, you can set the environment variables yourself.

For Windows users, run the following commands from a command prompt:

set BLIZZARD_CLIENT_ID=<YOUR_CLIENT_ID_GOES_HERE>
set BLIZZARD_CLIENT_SECRET=<YOUR_CLIENT_SECRET_GOES_HERE>

For POSIX users, run the following commands in a terminal:

export BLIZZARD_CLIENT_ID=<YOUR_CLIENT_ID_GOES_HERE>
export BLIZZARD_CLIENT_SECRET=<YOUR_CLIENT_SECRET_GOES_HERE>

Result

If successful, you will see a Spring Boot application console log which will allow you to submit a GET request at the following endpoint: http://localhost:8080/signature?characterName=CHARACTERNAME&realmName=REALMNAME

Note: make sure to use the programmatic realm name, ex: "Area 52" would be "area-52" in the URL

The result will be a signature generated describing the character.

Notes

This code makes heavy use of the Lombok library for both the @Data annotation and @Log4j2 annotations to save a lot of boilerplate code for POJOs and Logging.

Similarly, we use Spring's RestTemplate.exchange to execute our GET requests, and transform the results into Java objects, described by the above Lombok annotated classes. This was chosen, to allow the flexibility in submitting the token via header or via url parameter with minimal forking logic.

We recommend submitting your token in the header on general security principals, as the URL requested is frequently scraped and logged, which effectively steals an application's identity to make requests into our API system.

This is only intended as a launching point for developers to see an example application. There are many areas that could be improved.

There are many solutions for managing secrets and that topic is beyond the scope of this example to delve into. Please perform your own due-diligence when researching this topic and implementing it.