feat: Phase 1 Merchant Registry Contract Interaction

fluxapay_backend/.env.example

@@ -22,3 +22,9 @@ RESEND_API_KEY="re_your_resend_api_key_here"
 
 # Webhook
 WEBHOOK_SECRET="your-webhook-secret-here"
+
+# Soroban Smart Contracts
+SOROBAN_RPC_URL="https://soroban-testnet.stellar.org"
+SOROBAN_NETWORK_PASSPHRASE="Test SDF Network ; September 2015"
+MERCHANT_REGISTRY_CONTRACT_ID="C..."
+ADMIN_SECRET_KEY="S..."

fluxapay_backend/src/services/merchant.service.ts

@@ -4,6 +4,7 @@ import { createOtp, verifyOtp as verifyOtpService } from "./otp.service";
 import { sendOtpEmail } from "./email.service";
 import { isDevEnv } from "../helpers/env.helper";
 import { generateToken } from "../helpers/jwt.helper";
+import { merchantRegistryService } from "./merchantRegistry.service";
 
 
 const prisma = new PrismaClient();
@@ -47,6 +48,13 @@ export async function signupMerchantService(data: {
     },
   });
 
+  // On-chain registration (non-blocking)
+  merchantRegistryService.register_merchant(merchant.id, business_name, settlement_currency).catch(err => {
+    if (isDevEnv()) {
+      console.error("Non-blocking error during on-chain merchant registration:", err);
+    }
+  });
+
   // Generate OTP
   try {
     const otp = await createOtp(merchant.id, "email");

fluxapay_backend/src/services/merchantRegistry.service.ts

@@ -0,0 +1,126 @@
+import { Keypair, nativeToScVal, rpc, TransactionBuilder, Networks, Contract } from '@stellar/stellar-sdk';
+import { isDevEnv } from '../helpers/env.helper';
+
+export class MerchantRegistryService {
+    private rpcUrl: string;
+    private networkPassphrase: string;
+    private contractId: string;
+    private adminKeypair: Keypair;
+    private server: rpc.Server;
+
+    constructor() {
+        this.rpcUrl = process.env.SOROBAN_RPC_URL || 'https://soroban-testnet.stellar.org';
+        this.networkPassphrase = process.env.SOROBAN_NETWORK_PASSPHRASE || Networks.TESTNET;
+        this.contractId = process.env.MERCHANT_REGISTRY_CONTRACT_ID || '';
+
+        const adminSecret = process.env.ADMIN_SECRET_KEY;
+        if (adminSecret) {
+            this.adminKeypair = Keypair.fromSecret(adminSecret);
+        } else {
+            // Create a random one for dev/fallback if missing, though it won't actually have authorization on mainnet
+            this.adminKeypair = Keypair.random();
+            if (isDevEnv()) {
+                console.warn("ADMIN_SECRET_KEY not set. Using random keypair. Contract calls will likely fail.");
+            }
+        }
+
+        this.server = new rpc.Server(this.rpcUrl);
+    }
+
+    /**
+     * Registers a merchant on-chain via the Soroban Smart Contract.
+     * Includes an automatic retry mechanism for robustness.
+     */
+    public async register_merchant(merchantId: string, businessName: string, settlementCurrency: string): Promise<boolean> {
+        if (!this.contractId) {
+            console.warn("MERCHANT_REGISTRY_CONTRACT_ID is not configured. Skipping on-chain registration.");
+            return false;
+        }
+
+        const MAX_RETRIES = 3;
+        let attempt = 0;
+        const baseDelay = 1000;
+
+        while (attempt < MAX_RETRIES) {
+            try {
+                await this.invokeRegisterContract(merchantId, businessName, settlementCurrency);
+                if (isDevEnv()) {
+                    console.log(`Successfully registered merchant ${merchantId} on-chain.`);
+                }
+                return true;
+            } catch (error) {
+                attempt++;
+                let errorMessage = 'Unknown error';
+                if (error instanceof Error) errorMessage = error.message;
+
+                console.error(`Attempt ${attempt} to register merchant ${merchantId} on-chain failed:`, errorMessage);
+
+                if (attempt >= MAX_RETRIES) {
+                    // Log to manual intervention queue
+                    this.logToManualInterventionQueue(merchantId, errorMessage);
+                    return false;
+                }
+
+                // Exponential backoff
+                await new Promise(resolve => setTimeout(resolve, baseDelay * Math.pow(2, attempt - 1)));
+            }
+        }
+        return false;
+    }
+
+    private async invokeRegisterContract(merchantId: string, businessName: string, settlementCurrency: string) {
+        const contract = new Contract(this.contractId);
+
+        // Prepare arguments: merchant_id, business_name, settlement_currency
+        const args = [
+            nativeToScVal(merchantId, { type: 'string' }),
+            nativeToScVal(businessName, { type: 'string' }),
+            nativeToScVal(settlementCurrency, { type: 'symbol' })
+        ];
+
+        const sourceAccount = await this.server.getAccount(this.adminKeypair.publicKey());
+
+        const builder = new TransactionBuilder(sourceAccount, {
+            fee: '100000',
+            networkPassphrase: this.networkPassphrase,
+        });
+
+        const tx = builder
+            .addOperation(contract.call('register_merchant', ...args))
+            .setTimeout(30)
+            .build();
+
+        const preparedTx = await this.server.prepareTransaction(tx) as any;
+
+        preparedTx.sign(this.adminKeypair);
+
+        const sendTxResponse = await this.server.sendTransaction(preparedTx);
+
+        if (sendTxResponse.status === 'ERROR') {
+            throw new Error(`Transaction submission failed: ${JSON.stringify(sendTxResponse)}`);
+        }
+
+        // Wait for the transaction to be processed
+        let txResponse = await this.server.getTransaction(sendTxResponse.hash);
+
+        let retries = 0;
+        while (txResponse.status === 'NOT_FOUND' && retries < 10) {
+            await new Promise(resolve => setTimeout(resolve, 2000));
+            txResponse = await this.server.getTransaction(sendTxResponse.hash);
+            retries++;
+        }
+
+        if (txResponse.status === 'FAILED') {
+            throw new Error(`Transaction failed on-chain: ${JSON.stringify(txResponse)}`);
+        }
+
+        return txResponse;
+    }
+
+    private logToManualInterventionQueue(merchantId: string, reason: string) {
+        // In a real system, this would write to a database table or message queue
+        console.error(`[MANUAL INTERVENTION REQUIRED] Merchant ${merchantId} failed on-chain registration: ${reason}`);
+    }
+}
+
+export const merchantRegistryService = new MerchantRegistryService();