feat: add endpoint to fetch open DEX offers for an account #291

backend/src/middleware/validate.js

@@ -57,6 +57,11 @@
     .matches(STELLAR_PUBLIC_KEY)
     .withMessage('Invalid Stellar account ID'),
 
+  addressParam: param('address')
+    .trim()
+    .matches(STELLAR_PUBLIC_KEY)
+    .withMessage('Invalid Stellar address'),
+
   importAccount: [
     body('secretKey')
       .trim()
@@ -85,7 +90,7 @@
       .matches(ASSET_CODE)
       .withMessage('Invalid asset code')
       .isIn(SUPPORTED_ASSETS)
       .withMessage(`Unsupported asset. Supported: ${SUPPORTED_ASSETS.join(', ')}`),
     rules.memoField(),
     rules.memoTypeField(),
     // Cross-field: memo type 'id' requires a numeric memo value

backend/src/routes/accounts.js

@@ -0,0 +1,62 @@
+import express from 'express';
+import { getHorizonServer } from '../services/stellar.js';
+import { validate, rules } from '../middleware/validate.js';
+import logger from '../config/logger.js';
+
+const router = express.Router();
+
+/**
+ * @swagger
+ * /api/accounts/{address}/offers:
+ *   get:
+ *     summary: Get open DEX offers for an account
+ *     tags: [Accounts]
+ *     parameters:
+ *       - in: path
+ *         name: address
+ *         required: true
+ *         schema:
+ *           type: string
+ *         description: Stellar account address
+ *     responses:
+ *       200:
+ *         description: List of open offers
+ *       404:
+ *         description: Account not found
+ *       500:
+ *         description: Horizon connectivity error
+ */
+router.get('/:address/offers', rules.addressParam, validate, async (req, res) => {
+  const { address } = req.params;
+  const correlationId = req.correlationId;
+
+  try {
+    const server = getHorizonServer();
+    const response = await server.offers().forAccount(address).call();
+
+    const offers = response.records.map(o => ({
+      id: o.id,
+      selling_asset: o.selling.asset_type === 'native'
+        ? { type: 'native', code: 'XLM' }
+        : { type: o.selling.asset_type, code: o.selling.asset_code, issuer: o.selling.asset_issuer },
+      buying_asset: o.buying.asset_type === 'native'
+        ? { type: 'native', code: 'XLM' }
+        : { type: o.buying.asset_type, code: o.buying.asset_code, issuer: o.buying.asset_issuer },
+      amount: o.amount,
+      price: o.price,
+      last_modified_ledger: o.last_modified_ledger,
+    }));
+
+    logger.info('accounts.offers.fetched', { correlationId, address, count: offers.length });
+    res.json({ offers });
+  } catch (error) {
+    if (error?.response?.status === 404) {
+      logger.warn('accounts.offers.not_found', { correlationId, address });
+      return res.status(404).json({ error: 'Account not found' });
+    }
+    logger.error('accounts.offers.failed', { correlationId, address, error: error.message });
+    res.status(500).json({ error: 'Failed to fetch offers from Horizon' });
+  }
+});
+
+export default router;

backend/src/server.js

@@ -32,6 +32,7 @@ import { eventMonitor } from './eventSourcing/index.js';
 import streamingRoutes from './routes/streaming.js';
 import { processActiveStreams } from './services/streaming.js';
 import retryRoutes from './routes/retry.js';
+import accountsRoutes from './routes/accounts.js';
 import { auditLogger } from './security/index.js';
 import { getConfig } from './config/env.js';
 import { createRateLimiter } from './middleware/rateLimiter.js';
@@ -116,6 +117,7 @@ app.use('/api/cache', cacheRoutes);
 app.use('/api/streaming', streamingRoutes);
 app.use('/api/recovery', recoveryRoutes);
 app.use('/api/retry', retryRoutes);
+app.use('/api/accounts', accountsRoutes);
 
 // 404 handler for undefined routes
 app.use(notFoundHandler);