Add /ethprice API endpoint to fetch Ethereum price

app.js

@@ -1,11 +1,12 @@
 const express = require('express');
 const app = express();
-const port = 3000;
+const ethPriceRoutes = require('./src/routes/ethPriceRoutes');
 
-app.get('/', (req, res) => {
-  res.send('Hello World!');
-});
+app.use('/api', ethPriceRoutes);
 
+const port = process.env.PORT || 3000;
 app.listen(port, () => {
-  console.log(`Listening on http://localhost:${port}`);
-}); 
+  console.log(`Server running on port ${port}`);
+});
+
+module.exports = app;

package.json

@@ -1,12 +1,18 @@
 {
   "name": "express-hello-world",
   "version": "1.0.0",
-  "description": "一个简单的 Express Hello World 应用",
+  "description": "Express application with ETH price endpoint",
   "main": "app.js",
   "scripts": {
-    "start": "node app.js"
+    "start": "node app.js",
+    "test": "jest"
   },
   "dependencies": {
-    "express": "^4.18.2"
+    "express": "^4.18.2",
+    "node-fetch": "^2.6.1"
+  },
+  "devDependencies": {
+    "jest": "^27.0.0",
+    "supertest": "^6.1.6"
   }
-} 
+}

src/controllers/ethPriceController.js

@@ -0,0 +1,14 @@
+const EthPriceService = require('../services/ethPriceService');
+
+class EthPriceController {
+  static async getEthPrice(req, res) {
+    try {
+      const ethPrice = await EthPriceService.getEthPrice();
+      res.json({ price: ethPrice });
+    } catch (error) {
+      res.status(500).json({ error: error.message });
+    }
+  }
+}
+
+module.exports = EthPriceController;

src/routes/ethPriceRoutes.js

@@ -0,0 +1,8 @@
+const express = require('express');
+const EthPriceController = require('../controllers/ethPriceController');
+
+const router = express.Router();
+
+router.get('/ethprice', EthPriceController.getEthPrice);
+
+module.exports = router;

src/services/ethPriceService.js

@@ -0,0 +1,23 @@
+const fetch = require('node-fetch');
+
+class EthPriceService {
+  static async getEthPrice() {
+    const COINGECKO_API_URL = 'https://api.coingecko.com/api/v3/simple/price?ids=ethereum&vs_currencies=usd';
+
+    try {
+      const response = await fetch(COINGECKO_API_URL);
+
+      if (!response.ok) {
+        throw new Error('Unable to fetch Ethereum price');
+      }
+
+      const data = await response.json();
+      return data.ethereum.usd;
+    } catch (error) {
+      console.error('Error fetching ETH price:', error);
+      throw new Error('Failed to retrieve Ethereum price');
+    }
+  }
+}
+
+module.exports = EthPriceService;

tests/ethPriceEndpoint.test.js

@@ -0,0 +1,13 @@
+const request = require('supertest');
+const app = require('../app');
+
+describe('ETH Price Endpoint', () => {
+  it('should return a valid ETH price', async () => {
+    const response = await request(app).get('/api/ethprice');
+
+    expect(response.statusCode).toBe(200);
+    expect(response.body).toHaveProperty('price');
+    expect(typeof response.body.price).toBe('number');
+    expect(response.body.price).toBeGreaterThan(0);
+  });
+});