Verified Credential Issuance Demo

NOTE: This is a demo only. Do not use it in a production environment.

Description

This is a demo service that demonstrates the issuance of verified credentials directly to Polygon ID Wallet using the merklized on-chain issuer. The service utilizes on-chain anchoring through Merkle trees to ensure credential verifiability.

How It Works

1. Credential Issuance:

   • The service prepares the credential data
   • Generates a QR code containing the credential offer
   • Users receive the credential directly in their Polygon ID Wallet
   • The credential's Merkle root is anchored on-chain

2. Proof Generation:

   • Users can generate Merkle Tree Proofs (MTP) from their wallet
   • These proofs can be used to generate Zero-Knowledge proofs
   • The ZK proofs enable on-chain verification using an on-chain verifier

User Flow

1. Connect Wallet: Users connect their MetaMask wallet
2. Authentication: Users authenticate with their Google account
3. Credential Review: Users review their credential information
4. QR Code: Users scan a QR code with their Polygon ID wallet
5. Acceptance: Users receive and store the credential directly in their Polygon ID wallet

Quick Start Installation

Prerequisites

• Docker
• Docker-compose
• Ngrok
• Go (for utility tools)
• Node.js and npm (for contract deployment)

Setup Steps

1. Deploy the Contract

   # Clone the contracts repository
   git clone https://github.com/0xPolygonID/contracts.git
   cd contracts
   
   # Install dependencies and deploy
   npm install
   npm run deploy:identity:mumbai

2. Configure Environment

   # Copy environment template
   cp .env.example .env
   
   # Start ngrok tunnel
   ngrok http 8080

3. Calculate Issuer DID

   go run utils/convertor.go --contract_address=<ADDRESS_OF_ONCHAIN_ISSUER_CONTRACT>

   Options:

   • --contract_address: Contract address to convert to DID
   • --network: Network name (default: polygon)
   • --chain: Chain name (default: amoy)

4. Configure Environment Variables

   # Edit .env file with your values
   SUPPORTED_RPC="80002=<RPC_POLYGON_AMOY>"
   ISSUERS_PRIVATE_KEY="<ISSUER_DID>=<PRIVATE_KEY_OF_THE_CONTRACT_DEPLOYER>"
   EXTERNAL_HOST="<NGROK_URL>"

5. Build and Run

   docker-compose build
   docker-compose up -d

6. Access the application at: http://localhost:3000

Credential Verification

To verify credentials using the Query Builder:

1. Visit Query Builder

2. Configure the following:

   • Schema: ipfs://QmbbTKPTJy5zpS2aWBRps1duU8V3zC84jthpWDXE9mLHBX
   • Attribute: Select balance
   • Proof Type: Merkle Tree Proof (MTP)
   • Circuit ID: Credential Atomic Query MTP v2
   • Query Type: Choose appropriate type
   • Operator: Select if using Conditional query
   • Value: Provide if using Conditional query

3. Generate and scan the QR code with your Polygon ID wallet

Development

Project Structure

├── client/           # Frontend React application
├── server/           # Backend service
├── contracts/        # Smart contract interfaces
└── utils/           # Utility scripts and tools

Key Features

• On-chain credential anchoring
• Google OAuth integration
• MetaMask wallet connection
• QR code credential issuance
• MTP proof generation

License

verified-credential-issuance-demo is part of the 0xPolygonID project copyright 2024 ZKID Labs AG

This project is licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE)
• MIT license (LICENSE-MIT)

at your option.