Hedera Samples

Code samples to showcase Hedera integration, particularly how to request data from end-user with ShareRing Link and how to do some verifications against on-chain data.

The samples run on testenv in conjunction with a special test build.

Backend

The backend server consists of a couple APIs:

GET /sessions/:sessionId to get data of a particular session.

POST /sessions/webhook acts as a webhook, capturing data shared from user. This must be set as endpoint in ShareRing Link dashboard.

Important! The backend server is built on top of Ts.ED framework and requires Node >= 14, Express >= 4 and TypeScript >= 4.

Create an .env file following the .env.example:

PORT=8084
ONGO_URL=<mongodb connection string>
HEDERA_DID_CONTRACT_ADDRESS=<the DID contract address on hedera in 0x format>
HEDERA_OPERATOR_PRIVATE_KEY=<the operator private key in 0x format>
HEDERA_RELAY_API_ENDPOINT=<relayer endpoint e.g. https://testnet.hashio.io/api>

The verifications are done using ethers.js on the backend (or so called the web3 way).

See providers/hedera/services/HederaService.ts for all sample codes to perform the verifications.

Frontend

Frontend is a simple React webapp, bootstrapped with Create React App. It does mainly two things:

One, generates a ShareRing Link QR code with some parameters.

Two, makes call to the backend API to get and display session data and verification results.

Create ShareRing Link query

1. Get a subscription on ShareRing Link (testenv)
2. Create an endpoint pointing to the backend server /sessions/webhook. Can use the free Webhook.site and use whcli to receive data and forward to localhost.
3. Create a query, select the endpoint created above. Query must request the following information for verification purposes:

• ShareLedger_Address
• Matic_Address - this is the ethereum addess generated from the same seedphrase
• VCT token ID - the DID
• other information such as name, date_of_birth, etc.

Run the servers

The repo uses yarn as package manager. Install it first. At root directory:

# install dependencies
$ yarn install

# start backend
$ yarn start:backend

# start frontend
$ yarn start:frontend

By default, the backend runs on port :8084, and the frontend :3000.