Verifiable Credentials Demos

This repository contains multiple demo applications that demonstrate Verifiable Credentials (VC) and related OpenID flows for issuance and presentation. The demos are intentionally small, self-contained Spring Boot applications (Kotlin) and simple static frontends to illustrate concepts and integration points.

Quick overview

• Purpose: Provide runnable examples of issuing, holding (wallet), and verifying verifiable credentials using the OpenID for Verifiable Credential Issuance and Presentations specs.
• Tech stack: Java, Kotlin, Spring Boot, Thymeleaf (simple UI), Maven for build and test.
• Audience: Architects & developers learning about VCs.

Structure and modules

VC-Demo

A complete demo with issuer, wallet, and verifier

• issuer/ — Issuer Java Spring Boot app

  • Implements credential offer endpoints and the issuance flow (callback handling, token exchange, POST /credential) following OpenID for VC Issuance patterns.
  • Exposes endpoints used by wallets to fetch available credential offers and to request credentials.
  • Useful for running a local issuer during demos and tests.

• verifier/ — Verifier Java Spring Boot app

  • Demonstrates verifying verifiable presentations using OpenID for Verifiable Presentations flows.
  • Contains example verification logic (for demo scenarios such as age checks).

• wallet/ — Wallet (holder) Java Spring Boot app

  • A simple holder application that stores issued credentials and can start issuance flows against the issuer app.
  • Includes Thymeleaf-driven UI pages: List of available offers, credential details, and a "My Credentials" page with persisted issued credentials (in-memory by default).
  • Implements the OAuth2 authorization code flow callback and token exchange, posts authorization to /credential to complete issuance.

selective-disclosure-demo

Selective disclosure demo module

• Focused demo showing selective disclosure and presentation creation/verification, including UI pages with JSON previews of credential shapes and sample selective disclosure checks (for example, age >= 18).
• Includes an in-memory wallet and unit tests that mock remote issuer interactions.

mock-eudi-wallet-demo

Static EUDI wallet mock frontend

• A static, browser-based mock wallet that simulates basic wallet UI and behavior for testing and demos. Not a Spring app — just static HTML/JS/CSS.

Keycloak integration

Demos with Keycloak as VC issuer

See Keycloak-demo for instructions on how to set up a Keycloak server and configure the demos to use it.

Notes and troubleshooting

• Ports: If two apps try to use port 8080, set server.port or run them one at a time.
• Persistence: Wallets in these demos often use an in-memory store for simplicity. Data will be lost when the app restarts.
• Security: These demos are not production hardened. They show concepts and flows only.

Contributing

• Bug fixes, documentation improvements, and small features are welcome. Open a PR against the repository and include a short description of your change.

License

• See the LICENSE file at the repository root.