Add local Stellar demo seed command

veilend-backend/README.md

@@ -37,19 +37,25 @@ The application architecture is organized into distinct domain modules to clearl
 To maintain a consistent API structure, we enforce strict Data Transfer Object (DTO) validation and response formatting.
 
 ### Directory Structure
+
 Shared contracts and common code reside in `src/common`.
 
 ### DTO Validation
+
 - All controllers use NestJS `ValidationPipe`.
 - DTOs strictly define boundaries using `class-validator` decorators (e.g., `@IsString()`, `@IsNumber()`).
 - Data transformation uses `class-transformer` decorators (e.g., `@Type()`).
 
 ### Standardized Responses
+
 We utilize standard API wrapper formats to ensure predictable frontend consumption.
+
 - **Success/Error Wrapper**: `ApiResponseDto<T>` (e.g., `{ success: true, data: { ... } }`)
 
 ### Pagination
+
 For list-based endpoints, the following conventions apply:
+
 - **Request**: `PageOptionsDto` defines query options (`page`, `take`, `order`).
 - **Response**: `PageDto<T>` wraps an array of data alongside pagination metadata (`PageMetaDto`).
 
@@ -72,6 +78,30 @@ $ npm run start:dev
 $ npm run start:prod
 ```
 
+## Seed local Stellar demo data
+
+The local indexer read models are stored in `veilend-db.json`. To create a
+deterministic dataset for dashboard and history endpoint development, run:
+
+```bash
+$ npm run seed:local
+```
+
+The command writes representative Stellar lending activity to `veilend-db.json`:
+supported assets, user positions, and deposit/borrow/repay/withdraw history.
+After starting the API, the seeded records are available through:
+
+```bash
+$ curl http://localhost:3000/indexer/positions/GDEMOLOCALSTELLARLENDER00000000000000000000000000000001
+$ curl http://localhost:3000/indexer/transactions/GDEMOLOCALSTELLARBORROWER000000000000000000000000000001
+```
+
+To write the seed file somewhere else, pass an output path:
+
+```bash
+$ npm run seed:local -- --output ./tmp/veilend-db.json
+```
+
 ## Run tests
 
 ```bash

veilend-backend/package.json

@@ -12,6 +12,7 @@
     "start:dev": "nest start --watch",
     "start:debug": "nest start --debug --watch",
     "start:prod": "node dist/main",
+    "seed:local": "node scripts/seed-local-stellar-data.mjs",
     "lint": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
     "test": "jest",
     "test:watch": "jest --watch",

veilend-backend/scripts/seed-local-stellar-data.mjs

@@ -0,0 +1,160 @@
+import { mkdir, writeFile } from 'node:fs/promises';
+import path from 'node:path';
+
+const DEFAULT_OUTPUT = path.join(process.cwd(), 'veilend-db.json');
+const FIXED_TIMESTAMP = '2026-01-15T12:00:00.000Z';
+
+const args = process.argv.slice(2);
+
+function readOption(name) {
+  const prefix = `${name}=`;
+  const inline = args.find((arg) => arg.startsWith(prefix));
+  if (inline) return inline.slice(prefix.length);
+
+  const index = args.indexOf(name);
+  if (index !== -1) return args[index + 1];
+
+  return undefined;
+}
+
+const outputPath = path.resolve(
+  readOption('--output') || process.env.VEILEND_SEED_OUTPUT || DEFAULT_OUTPUT,
+);
+
+const users = {
+  lender: 'GDEMOLOCALSTELLARLENDER00000000000000000000000000000001',
+  borrower: 'GDEMOLOCALSTELLARBORROWER000000000000000000000000000001',
+};
+
+const assets = {
+  usdc: 'CCW57ZST4NV43YS7JZKMGLG62624NV43YS7JZKMGLG62624USDC',
+  xlm: 'CCW57ZST4NV43YS7JZKMGLG62624NV43YS7JZKMGLG62624XLM1',
+};
+
+function transaction(
+  id,
+  userAddress,
+  type,
+  assetAddress,
+  amount,
+  ledger,
+  txHash,
+) {
+  return {
+    id,
+    userAddress,
+    type,
+    assetAddress,
+    amount,
+    ledger,
+    txHash,
+    timestamp: new Date(Date.parse(FIXED_TIMESTAMP) + ledger).toISOString(),
+  };
+}
+
+const seed = {
+  checkpoint: { lastIndexedLedger: 424242 },
+  transactions: [
+    transaction(
+      'demo-424201-0001',
+      users.lender,
+      'deposit',
+      assets.usdc,
+      '2500000000',
+      424201,
+      'demo_tx_424201_deposit_usdc',
+    ),
+    transaction(
+      'demo-424202-0001',
+      users.borrower,
+      'deposit',
+      assets.xlm,
+      '5000000000',
+      424202,
+      'demo_tx_424202_deposit_xlm',
+    ),
+    transaction(
+      'demo-424203-0001',
+      users.borrower,
+      'borrow',
+      assets.usdc,
+      '750000000',
+      424203,
+      'demo_tx_424203_borrow_usdc',
+    ),
+    transaction(
+      'demo-424204-0001',
+      users.borrower,
+      'repay',
+      assets.usdc,
+      '125000000',
+      424204,
+      'demo_tx_424204_repay_usdc',
+    ),
+    transaction(
+      'demo-424205-0001',
+      users.lender,
+      'withdraw',
+      assets.usdc,
+      '250000000',
+      424205,
+      'demo_tx_424205_withdraw_usdc',
+    ),
+  ],
+  positions: [
+    {
+      userAddress: users.lender,
+      assetAddress: assets.usdc,
+      deposited: '2250000000',
+      borrowed: '0',
+      updatedAt: FIXED_TIMESTAMP,
+    },
+    {
+      userAddress: users.borrower,
+      assetAddress: assets.xlm,
+      deposited: '5000000000',
+      borrowed: '0',
+      updatedAt: FIXED_TIMESTAMP,
+    },
+    {
+      userAddress: users.borrower,
+      assetAddress: assets.usdc,
+      deposited: '0',
+      borrowed: '625000000',
+      updatedAt: FIXED_TIMESTAMP,
+    },
+  ],
+  assets: [
+    {
+      assetAddress: assets.usdc,
+      supported: true,
+      updatedAt: FIXED_TIMESTAMP,
+    },
+    {
+      assetAddress: assets.xlm,
+      supported: true,
+      updatedAt: FIXED_TIMESTAMP,
+    },
+    {
+      assetAddress: 'CCW57ZST4NV43YS7JZKMGLG62624NV43YS7JZKMGLG62624DISA',
+      supported: false,
+      updatedAt: FIXED_TIMESTAMP,
+    },
+  ],
+};
+
+const seenTransactionIds = new Set();
+for (const tx of seed.transactions) {
+  if (seenTransactionIds.has(tx.id)) {
+    throw new Error(`Duplicate seed transaction id: ${tx.id}`);
+  }
+  seenTransactionIds.add(tx.id);
+}
+
+await mkdir(path.dirname(outputPath), { recursive: true });
+await writeFile(outputPath, `${JSON.stringify(seed, null, 2)}\n`, 'utf8');
+
+console.log(`Seeded VeilLend local indexer data at ${outputPath}`);
+console.log(
+  `Created ${seed.assets.length} assets, ${seed.positions.length} positions, and ${seed.transactions.length} transactions.`,
+);