Add compound XDR builder endpoint

package.json

@@ -7,6 +7,7 @@
   "license": "UNLICENSED",
   "scripts": {
     "build": "nest build",
+    "postinstall": "prisma generate",
     "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\"",
     "start": "nest start",
     "start:dev": "nest start --watch",
@@ -35,11 +36,11 @@
     "@nestjs/config": "^3.2.3",
     "@nestjs/core": "^10.4.22",
     "@nestjs/platform-express": "^10.4.22",
-    "@nestjs/platform-socket.io": "^10.0.0",
+    "@nestjs/platform-socket.io": "^10.4.22",
     "@nestjs/swagger": "^7.1.1",
     "@nestjs/throttler": "^6.5.0",
     "@nestjs/typeorm": "^10.0.2",
-    "@nestjs/websockets": "^10.0.0",
+    "@nestjs/websockets": "^10.4.22",
     "@prisma/client": "^5.19.1",
     "@stellar/stellar-sdk": "^11.0.0",
     "@types/jsonwebtoken": "^9.0.10",

prisma/schema.prisma

@@ -1,4 +1,4 @@
-// This is your Prisma schema file,
+// This is your Prisma schema file,
 // learn more about it in the docs: https://pris.ly/d/prisma-schema
 
 generator client {

src/app.module.ts

@@ -18,6 +18,7 @@ import { ConfigModule } from '@nestjs/config';
 import { MaintenanceMiddleware } from './common/middleware/maintenance.middleware';
 import { RequestIdMiddleware } from './common/middleware/request-id.middleware';
 import { RedisModule } from './common/redis/redis.module';
+import { TransactionsModule } from './transactions/transactions.module';
 
 @Module({
   imports: [
@@ -32,6 +33,7 @@ import { RedisModule } from './common/redis/redis.module';
     TokensModule, 
     OgModule,
     TradeModule,
+    TransactionsModule,
     OrdersModule,
     GasModule,
   ],

src/common/logger/custom.logger.ts

@@ -1,4 +1,4 @@
-import { ConsoleLogger, Injectable, Scope } from '@nestjs/common';
+import { ConsoleLogger, Injectable, LogLevel, Scope } from '@nestjs/common';
 import { requestContextStorage } from '../storage/request-context.storage';
 
 /**
@@ -19,7 +19,7 @@ export class CustomLogger extends ConsoleLogger {
    * @returns The fully formatted log string.
    */
   formatMessage(
-    logLevel: string,
+    logLevel: LogLevel,
     message: unknown,
     pidMessage: string,
     formattedLogLevel: string,

src/dynamic/dynamic.module.ts

@@ -1,6 +1,6 @@
 import { Module } from '@nestjs/common';
-import { InvoicesController } from './invoices.controller';
-import { PdfService } from './pdf.service';
+import { InvoicesController } from '../invoices/invoices.controller';
+import { PdfService } from '../invoices/pdf.service';
 
 @Module({
   controllers: [InvoicesController],

src/gas/gas.service.ts

@@ -1,6 +1,6 @@
 import { Injectable, Logger } from '@nestjs/common';
 import { RedisService } from '../common/redis/redis.service';
-import { Server } from '@stellar/stellar-sdk/rpc';
+import { SorobanRpc } from '@stellar/stellar-sdk';
 
 export interface FeeTiers {
   low: string;
@@ -33,9 +33,9 @@ export class GasService {
   private async fetchAndCache() {
     try {
       const rpcUrl = process.env.STELLAR_RPC_URL || 'https://soroban-testnet.stellar.org';
-      const server = new Server(rpcUrl);
-      const ledger = await server.getLatestLedger();
-      const baseFee = parseInt(ledger.baseFeeInStroops || '100', 10);
+      const server = new SorobanRpc.Server(rpcUrl);
+      await server.getLatestLedger();
+      const baseFee = parseInt(process.env.STELLAR_BASE_FEE_STROOPS || '100', 10);
 
       const tiers: FeeTiers = {
         low: Math.ceil(baseFee * 1.0).toString(),

src/pools/pools.controller.ts

@@ -3,6 +3,11 @@ import { ApiOperation, ApiParam, ApiResponse, ApiTags } from '@nestjs/swagger';
 import { ApyHistoryPoint, generateMockApyHistory } from './apy-history.helper';
 import { PoolIdParamDto } from './dto/pool-id-param.dto';
 
+interface ApyHistoryResponse {
+  status: 'success';
+  data: ApyHistoryPoint[];
+}
+
 /**
  * Controller for liquidity pool information and history.
  * Provides simulated APY history and recent trade data for pools.
@@ -23,11 +28,22 @@ export class PoolsController {
   @ApiResponse({
     status: 200,
     description: 'APY history retrieved successfully',
-    type: ApyHistoryPoint,
-    isArray: true,
+    schema: {
+      type: 'object',
+      properties: {
+        status: { type: 'string', example: 'success' },
+        data: {
+          type: 'array',
+          items: { $ref: '#/components/schemas/ApyHistoryPoint' },
+        },
+      },
+    },
   })
-  getApyHistory(@Param() params: PoolIdParamDto): ApyHistoryPoint[] {
-    return generateMockApyHistory(params.poolId);
+  getApyHistory(@Param() params: PoolIdParamDto): ApyHistoryResponse {
+    return {
+      status: 'success',
+      data: generateMockApyHistory(params.poolId),
+    };
   }
 
   /**
@@ -97,4 +113,3 @@ export class PoolsController {
     };
   }
 }
-

src/trade/trade.gateway.ts

@@ -1,7 +1,7 @@
-import { WebSocketGateway, WebSocketServer, OnModuleInit } from '@nestjs/websockets';
+import { OnModuleInit, Logger } from '@nestjs/common';
+import { WebSocketGateway, WebSocketServer } from '@nestjs/websockets';
 import { Server } from 'socket.io';
 import { RedisService } from '../common/redis/redis.service';
-import { Logger } from '@nestjs/common';
 
 /**
  * WebSocket Gateway for real-time trade updates.

src/transactions/transactions.controller.spec.ts

@@ -0,0 +1,68 @@
+import { INestApplication } from '@nestjs/common';
+import { Test, TestingModule } from '@nestjs/testing';
+import { Keypair, Networks } from '@stellar/stellar-sdk';
+import * as request from 'supertest';
+import { TransactionsModule } from './transactions.module';
+import { TransactionsService } from './transactions.service';
+
+describe('TransactionsController', () => {
+  let app: INestApplication;
+  const source = Keypair.random().publicKey();
+  const destination = Keypair.random().publicKey();
+
+  const transactionsService = {
+    buildTransaction: jest.fn(),
+  };
+
+  beforeAll(async () => {
+    const moduleFixture: TestingModule = await Test.createTestingModule({
+      imports: [TransactionsModule],
+    })
+      .overrideProvider(TransactionsService)
+      .useValue(transactionsService)
+      .compile();
+
+    app = moduleFixture.createNestApplication();
+    await app.init();
+  });
+
+  beforeEach(() => {
+    transactionsService.buildTransaction.mockResolvedValue({
+      xdr: 'AAAA',
+      source,
+      operationCount: 1,
+      networkPassphrase: Networks.TESTNET,
+    });
+  });
+
+  afterAll(async () => {
+    await app.close();
+  });
+
+  it('POST /api/v1/transactions/build delegates to the transaction builder service', async () => {
+    const payload = {
+      source,
+      operations: [
+        {
+          type: 'payment',
+          destination,
+          asset: { type: 'native' },
+          amount: '1.0000000',
+        },
+      ],
+    };
+
+    const response = await request(app.getHttpServer())
+      .post('/api/v1/transactions/build')
+      .send(payload)
+      .expect(200);
+
+    expect(transactionsService.buildTransaction).toHaveBeenCalledWith(payload);
+    expect(response.body).toEqual({
+      xdr: 'AAAA',
+      source,
+      operationCount: 1,
+      networkPassphrase: Networks.TESTNET,
+    });
+  });
+});

src/transactions/transactions.controller.ts

@@ -0,0 +1,35 @@
+import { Body, Controller, HttpCode, HttpStatus, Post } from '@nestjs/common';
+import { ApiBody, ApiOperation, ApiResponse, ApiTags } from '@nestjs/swagger';
+import { BuildTransactionDto, TransactionsService } from './transactions.service';
+
+@ApiTags('transactions')
+@Controller('api/v1/transactions')
+export class TransactionsController {
+  constructor(private readonly transactionsService: TransactionsService) {}
+
+  @Post('build')
+  @HttpCode(HttpStatus.OK)
+  @ApiOperation({ summary: 'Build an unsigned Stellar transaction envelope' })
+  @ApiBody({
+    schema: {
+      type: 'object',
+      required: ['source', 'operations'],
+      properties: {
+        source: { type: 'string', description: 'Source Stellar public key' },
+        fee: { type: 'string', description: 'Optional per-operation fee in stroops' },
+        networkPassphrase: { type: 'string', description: 'Optional Stellar network passphrase' },
+        timeoutSeconds: { type: 'number', description: 'Optional transaction timeout in seconds' },
+        operations: {
+          type: 'array',
+          description: 'Sequential payment or pathPaymentStrictSend intents',
+          items: { type: 'object' },
+        },
+      },
+    },
+  })
+  @ApiResponse({ status: 200, description: 'Unsigned base64 XDR envelope built successfully' })
+  @ApiResponse({ status: 400, description: 'Invalid transaction build request' })
+  async buildTransaction(@Body() body: BuildTransactionDto) {
+    return this.transactionsService.buildTransaction(body);
+  }
+}

src/transactions/transactions.module.ts

@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { TransactionsController } from './transactions.controller';
+import { TransactionsService } from './transactions.service';
+
+@Module({
+  controllers: [TransactionsController],
+  providers: [TransactionsService],
+})
+export class TransactionsModule {}

src/transactions/transactions.service.spec.ts

@@ -0,0 +1,66 @@
+import { Account, Keypair, Networks, TransactionBuilder } from '@stellar/stellar-sdk';
+import { BadRequestException } from '@nestjs/common';
+import { TransactionsService } from './transactions.service';
+
+describe('TransactionsService', () => {
+  const source = Keypair.random().publicKey();
+  const firstDestination = Keypair.random().publicKey();
+  const secondDestination = Keypair.random().publicKey();
+  const issuer = Keypair.random().publicKey();
+
+  const accountLoader = {
+    loadAccount: jest.fn(),
+  };
+
+  beforeEach(() => {
+    accountLoader.loadAccount.mockResolvedValue(new Account(source, '123'));
+  });
+
+  it('builds an unsigned XDR envelope from sequential swap intents', async () => {
+    const service = new TransactionsService(accountLoader);
+
+    const result = await service.buildTransaction({
+      source,
+      fee: '200',
+      networkPassphrase: Networks.TESTNET,
+      operations: [
+        {
+          type: 'pathPaymentStrictSend',
+          sendAsset: { type: 'native' },
+          sendAmount: '10.0000000',
+          destination: firstDestination,
+          destAsset: { type: 'credit_alphanum4', code: 'USDC', issuer },
+          destMin: '9.5000000',
+          path: [{ type: 'credit_alphanum4', code: 'EURC', issuer }],
+        },
+        {
+          type: 'payment',
+          destination: secondDestination,
+          asset: { type: 'native' },
+          amount: '1.0000000',
+        },
+      ],
+    });
+
+    expect(accountLoader.loadAccount).toHaveBeenCalledWith(source);
+    expect(result.source).toBe(source);
+    expect(result.operationCount).toBe(2);
+    expect(typeof result.xdr).toBe('string');
+
+    const transaction = TransactionBuilder.fromXDR(result.xdr, Networks.TESTNET) as any;
+    expect(transaction.operations).toHaveLength(2);
+    expect(transaction.operations[0].type).toBe('pathPaymentStrictSend');
+    expect(transaction.operations[1].type).toBe('payment');
+  });
+
+  it('rejects empty operation arrays', async () => {
+    const service = new TransactionsService(accountLoader);
+
+    await expect(
+      service.buildTransaction({
+        source,
+        operations: [],
+      }),
+    ).rejects.toBeInstanceOf(BadRequestException);
+  });
+});