OAuth2 Authorization Server with Spring Boot 4 and Java 25

Prerequisites

Java 25 should be installed --> export JAVA_HOME=$(/usr/libexec/java_home -v 25)
Maven should be installed
Docker should be installed
Postman can be installed

How to Run and Test

Run the following commands to set environment variables for AI model API keys
```bash

export OPENAI_API_KEY=your_api_key_here

export DEEPSEEK_API_KEY=your_api_key_here

export ANTHROPIC_API_KEY=your_api_key_here # Optional

export GOOGLE_GENAI_API_KEY=your_api_key_here # Optional

code

- ```bash
    cd oauth2-authorization-server
    
    # Run tests on the host (requires Docker for Testcontainers)
    mvn clean verify
    
    # Build and start the application together with all infrastructure services
    docker compose --profile start_application up -d --build
    
    # Start only infrastructure services (Redis, MariaDB, LDAP, Ollama, etc.)
    docker compose up -d
    
    # For local development without Docker (requires infrastructure services running via docker compose up -d)
    ./mvnw spring-boot:run   # or: mvn spring-boot:run

Import the followings to test in Postman
OAuth2 Authorization Server.postman_collection.json
OAuth2 Authorization Server.postman_environment.json
Swagger: http://localhost:9000/swagger-ui/index.html
Click Authorize and enter the following credentials
client_id: client
client_secret: secret
Use one of the following default values to log in http://localhost:9000/login
username: Developer password: password
username: Admin password: password
username: User password: password
Actuator: http://localhost:9000/actuator/
Database credentials
url: jdbc:mariadb://localhost:3306/oauth2_authorization_server
username: mb_test
password: test
Redis
host: localhost
port: 6379
Redis Insight: http://localhost:5540/
Click Add Redis database
Connection URL --> redis://default@host.docker.internal:6379
Click Add Database
Ollama
http://localhost:3000/ sign up for an account for local environment
Search for mxbai-embed-large and download it if it does not exist
Search for mistral and download it if it does not exist
Search for deepseek-r1:7b and download it if it does not exist
Grafana UI
http://localhost:3001/
username: admin
password: admin

Debugging Spring Boot Tests in IntelliJ IDEA

1. Run one of the below commands in the terminal

mvn test -Dmaven.surefire.debug
If port 5005 is already in use, you can specify a custom port
mvn test -Dmaven.surefire.debug="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000"

2. Open IntelliJ IDEA

3. Go to Run > Attach to Process (or use shortcut)

Windows/Linux: Ctrl + Alt + 5
Mac: Cmd + Alt + 5

4. Select the Java process running your tests

5. The test will pause until you connect your debugger. Once connected, you can use breakpoints and step through your

code.

Java 25+ should be installed
Run ./mvnw clean install or./mvnw clean install -Paot or ./mvnw -Paot package command to build the application

with AOT

Run docker-compose up -d command to run necessary services
Run docker build -t oauth2-authorization-server -f DockerfileForAOTCache . command to build the image
Run docker run -d --restart=always -p 9000:9000 oauth2-authorization-server:latest command to run the image

How to Run and Test Native Image with GraalVM

Java 25 GraalVM edition should be installed
Run docker-compose up -d command to run necessary services
Run ./mvnw -Pnative native:compile or ./mvnw -Pnative native:compile -DskipTests command to build the native image
Run ./target/oauth2-authorization-server command to run the native image
Install Grype (OPTIONAL)
Run native-image-inspect ./target/oauth2-authorization-server-0.0.1 | grype -v command to scan vulnerabilities
Run native-image-inspect ./target/oauth2-authorization-server-0.0.1 >output.json command and open output.json or

visit http://localhost:9000/actuator/sbom/native-image to inspect all libraries, methods etc. used in the native image

Run open ./target/oauth2-authorization-server-build-report.html to see build report
Use Swagger UI to test the application

Spring Boot with CRaC(Coordinated Restore at Checkpoint) by Creating Ready to Restore Container Image.

Warning: for real projects make sure to not leak sensitive data in CRaC files since they contain a snapshot of the

memory of the running JVM instance.

Checkpoint
Run

on demand checkpoint/restore of a running application

with: ./docs/scripts/checkpoint.sh

an automatic checkpoint/restore at startup

with: ./docs/scripts/checkpointOnRefresh.sh

Restore
Restore the application with: ./docs/scripts/restore.sh
Use Swagger UI to test the application

How to Run and Test AI Models Locally with Docker Desktop Model Runner

Requires: Docker Desktop 4.40 and later
Run docker-compose up -d command to run necessary services
Run docker model pull ai/gemma3:4B-Q4_K_M command to pull the model
Run docker model run ai/gemma3:4B-Q4_K_M command to run the model to test it from the command line (OPTIONAL)
Docker Desktop --> Settings --> Features in development --> Beta features --> Enable Docker Model Runner -->

Enable host-side TCP support --> Apply & Restart

Run mvn test or mvn clean install or mvn clean package or ./mvnw clean install command to run all the tests
Run mvn spring-boot:run command to run the application
Use Swagger UI to test the application

Dependency Version Management

Dependency versions are managed via

the Maven Versions Plugin and a version-rules.xml filter

that excludes alpha/beta/RC/SNAPSHOT releases.

Local — using the helper script:

bash

./docs/scripts/update-versions.sh check           # Show all outdated versions (parent + props + deps + plugins)
./docs/scripts/update-versions.sh update          # Auto-update everything and review with: git diff pom.xml
./docs/scripts/update-versions.sh update-props    # Update only  versions (safest)
./docs/scripts/update-versions.sh update-parent   # Update only spring-boot-starter-parent
./docs/scripts/update-versions.sh revert          # Revert pom.xml from backup

CI/CD — automated PR creation:

The MB Dependency Version Update workflow runs every Monday (and on-demand),

checks for updates, verifies the build compiles, and creates a PR automatically.

Oauth2 Authorization Server

Documentation