@sapliyio/fintech

Official Node.js SDK for the Sapliy Fintech Ecosystem. Build robust financial applications with a modern, type-safe SDK.

Features

• Payments — Create charges, handle refunds, manage payment lifecycle
• Wallets — User balances and internal accounting
• Ledger — Double-entry bookkeeping for high-integrity transactions
• Billing — Subscriptions and recurring billing
• Connect — Multi-tenant support and managed accounts
• Webhooks — Event handling with signature verification
• TypeScript — Full type definitions included
• Events — Emit events to trigger flows

Installation

npm install @sapliyio/fintech
# or
yarn add @sapliyio/fintech

Quick Start

import { FintechClient } from '@sapliyio/fintech';

const client = new FintechClient('sk_test_...');

// Create a payment
const payment = await client.payments.create({
  amount: 2000, // $20.00
  currency: 'USD',
  sourceId: 'src_123',
  description: 'Order #1234'
});

console.log('Payment created:', payment.id);

Configuration

// Custom base URL (for self-hosted)
const client = new FintechClient('sk_test_...', {
  baseUrl: 'https://api.yourdomain.com'
});

// Custom timeout
const client = new FintechClient('sk_test_...', {
  timeout: 30000 // 30 seconds
});

API Reference

Payments

// Create a charge
const payment = await client.payments.create({
  amount: 1000,
  currency: 'USD',
  sourceId: 'src_123',
  description: 'Coffee'
});

// Get payment details
const payment = await client.payments.get('pay_123');

// Refund a payment
const refund = await client.payments.refund('pay_123', 500); // partial refund

Wallets

// Create a wallet
const wallet = await client.wallets.create({
  name: 'User Wallet',
  currency: 'USD'
});

// Get wallet balance
const wallet = await client.wallets.get('wal_123');

// Credit (add funds)
const wallet = await client.wallets.credit('wal_123', {
  amount: 1000,
  description: 'Deposit'
});

// Debit (withdraw funds)
const wallet = await client.wallets.debit('wal_123', {
  amount: 500,
  description: 'Purchase'
});

Ledger

// Record a transaction
const response = await client.ledger.recordTransaction({
  accountId: 'acc_123',
  amount: 1000,
  currency: 'USD',
  description: 'Payment received',
  referenceId: 'ref_456'
});

// Get account details
const account = await client.ledger.getAccount('acc_123');
console.log('Balance:', account.balance);

Billing

// Create a subscription
const subscription = await client.billing.createSubscription({
  customerId: 'cust_123',
  planId: 'plan_monthly'
});

// Get subscription
const subscription = await client.billing.getSubscription('sub_123');

// Cancel subscription
await client.billing.cancelSubscription('sub_123');

Events (Automation)

// Emit an event to trigger flows
await client.events.emit('checkout.completed', {
  cartId: 'cart_123',
  total: 5000,
  customerId: 'cust_456'
});

Flow Builder Template Variables

When creating flows in the Sapliy Flow Builder, you can use Handlebars template syntax to dynamically reference event data in your automation logic. This is particularly useful for approval messages, webhook payloads, and conditional logic.

Available Variables

Variable	Description	Example
{{event.type}}	The event type that triggered the flow	payment.completed
{{event.id}}	Unique event identifier	evt_abc123
{{event.payload.*}}	Access any field from the event payload	{{event.payload.amount}}
{{event.createdAt}}	Timestamp when event was created	2024-01-15T10:30:00Z

Usage Examples

Approval Node Message

Approval required for payment of ${{event.payload.amount}} {{event.payload.currency}}
Customer: {{event.payload.customerId}}

When you emit an event like:

await client.events.emit('payment.high_value', {
  amount: 10000,
  currency: 'USD',
  customerId: 'cust_456'
});

The approval message will render as:

Approval required for payment of $10000 USD
Customer: cust_456

Webhook Payload Template

{
  "orderId": "{{event.payload.orderId}}",
  "status": "approved",
  "approvedAt": "{{event.createdAt}}",
  "amount": {{event.payload.amount}}
}

Conditional Logic

Use template variables in condition nodes to create dynamic flow logic:

{{event.payload.amount}} > 5000

Best Practices

1. Always validate data exists: Use the Flow Builder's test mode to ensure your template variables resolve correctly
2. Type safety: Numeric fields don't need quotes in JSON templates: {{amount}} not "{{amount}}"
3. Nested objects: Access nested data with dot notation: {{event.payload.customer.email}}
4. Debugging: Use sapliy listen to see the actual event payloads and verify your template paths

Webhook Handling

Express

import express from 'express';
import { FintechClient } from '@sapliyio/fintech';

const app = express();
const client = new FintechClient('sk_test_...');

app.post('/webhooks', express.raw({ type: 'application/json' }), (req, res) => {
  const signature = req.headers['x-sapliy-signature'] as string;
  const secret = process.env.SAPLIY_WEBHOOK_SECRET!;

  try {
    const event = client.webhooks.constructEvent(req.body, signature, secret);

    switch (event.type) {
      case 'payment.succeeded':
        const payment = event.data.object;
        console.log('Payment succeeded:', payment.id);
        break;
      case 'payment.failed':
        console.log('Payment failed');
        break;
    }
  } catch (err) {
    return res.status(400).send(`Webhook Error: ${err.message}`);
  }

  res.json({ received: true });
});

Next.js (App Router)

// app/api/webhooks/route.ts
import { NextRequest, NextResponse } from 'next/server';
import { FintechClient } from '@sapliyio/fintech';

const client = new FintechClient(process.env.SAPLIY_SECRET_KEY!);

export async function POST(req: NextRequest) {
  const payload = await req.text();
  const signature = req.headers.get('x-sapliy-signature')!;
  const secret = process.env.SAPLIY_WEBHOOK_SECRET!;

  try {
    const event = client.webhooks.constructEvent(payload, signature, secret);

    if (event.type === 'payment.succeeded') {
      // Handle successful payment
    }

    return NextResponse.json({ received: true });
  } catch (err) {
    return NextResponse.json({ error: 'Invalid signature' }, { status: 400 });
  }
}

Error Handling

import { FintechError, PaymentError } from '@sapliyio/fintech';

try {
  await client.payments.get('invalid_id');
} catch (error) {
  if (error instanceof PaymentError) {
    console.log('Payment error:', error.message);
  } else if (error instanceof FintechError) {
    console.log(`API error (${error.statusCode}):`, error.message);
  }
}

TypeScript Support

Full TypeScript definitions are included:

import {
  FintechClient,
  Payment,
  Wallet,
  Subscription,
  WebhookEvent
} from '@sapliyio/fintech';

const handlePayment = (payment: Payment) => {
  console.log(payment.id, payment.amount, payment.status);
};

Part of Sapliy Fintech Ecosystem

• fintech-ecosystem — Core backend
• fintech-sdk-go — Go SDK
• fintech-sdk-python — Python SDK
• fintech-ui — React components
• sapliy-cli — Developer CLI

See ARCHITECTURE.md for the full system design.

License

MIT © Sapliy