# Issuing Credentials

**What We Are Doing:**

* Setting up a minimal Express application in `src/index.js` that:
  * Loads environment variables (via `dotenv`).
  * Serves static files from a `public/` directory.
  * Mounts our router (where the `/kyc-credential` route will live).

**Why:** Before we can implement any credential-related endpoints, we need a working Express server that can:

* Host our frontend assets (HTML/CSS/JS) under `public/`.
* Accept POST requests (JSON/form data) from the frontend.
* Delegate route handling to `src/issuer-routes.js`.
* Spin up on a known port so the frontend and wallet callbacks work correctly.

**Steps:** Create `src/index.js` with the following contents:

```javascript
import express from "express";
import path from "path";
import {fileURLToPath} from "url";
import dotenv from "dotenv";
import issuerRouter from "./issuer-routes.js";
import jwt from "jsonwebtoken";

dotenv.config();

// Convert module URL to a __dirname-like value
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// PORT and BASE_URL come from .env (fallback to 3000 if not set)
const PORT = process.env.PORT || 3000;
const BASE_URL = process.env.BASE_URL || `http://localhost:${PORT}`;

// Initialize Express app
const app = express();

// Serve any static assets (e.g., index.html, scripts, styles) from public/
app.use(express.static(path.join(__dirname, "../public")));

// Parse URL-encoded bodies (HTML form submissions)
app.use(express.urlencoded({extended: true}));

// Attach our router (defined in src/issuer-routes.js)
app.use("/issuer", express.json(), issuerRouter);

// Start the server
app.listen(PORT, () => {
  console.log(`Server is running on ${BASE_URL}`);
});
```

To `.env` file, add the following variables:

```env
PORT=3000

BASE_URL=http://192.168.1.1:3000 # or your desired base URL it should match the URL of your server + the port. 
# It cannot be localhost because the Empe DID Wallet needs to access it from a mobile device

JWT_SECRET=`your-jwt-secret` # a secret key for signing JWTs, used later for authorization
```

Also make sure you have `ISSUER_URL` and `ISSUER_SECRET` set in your `.env` file as described in the [Deploying the Issuer](https://github.com/empe-io/docs/blob/master/tech-doc/getting-started/tutorial/develop-on-empe/tutorial/03-deploying-issuer.md).

***

**Issuing Credentials**

**What We Are Doing:**

* Implementing a route (`/kyc-credential`) in our Express app that:
  * Takes user input (age, firstName, lastName).
  * Contacts the Issuer to create a credential issuance offering.
  * Returns the offering data, including a `qr_code_url`.

**Why:** This route enables users to input their info and receive a QR code. Scanning the QR code with the Empe DID Wallet allows them to claim the credential.

**Steps:** Update `src/issuer-routes.js`:

```javascript
import {Router} from "express";
import fetch from "node-fetch";
import dotenv from "dotenv";

dotenv.config();

const router = Router();
const ISSUER_URL = process.env.ISSUER_URL;
const ISSUER_SECRET = process.env.ISSUER_SECRET;

router.post("/kyc-credential", async (req, res) => {
  try {
    const {age, firstName, lastName} = req.body;
    // Fetch issuer metadata to get offering_endpoint
    const metadataRes = await fetch(`${ISSUER_URL}/.well-known/openid-credential-issuer`);
    const metadata = await metadataRes.json();
    const offering_endpoint = metadata.offering_endpoint;
    // Request an issuance offering from the Issuer
    const offeringRes = await fetch(offering_endpoint, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
        "x-client-secret": ISSUER_SECRET,
      },
      body: JSON.stringify({
        credential_type: "KYC Verifiable Credential",
        credential_subject: {age: Number(age), firstName, lastName},
      }),
    });

    const offeringData = await offeringRes.json();
    res.status(200).json(offeringData);
  } catch (error) {
    console.error(error);
    res.status(500).json({error: "Internal server error"});
  }
});

export default router;
```

## Run the server:

```bash
  node src/index.js
```

Next, we will create a simple frontend form to submit user data and display the QR code.