Send online orders to SyncPay

Same API for point of sale: developers-pos.html.

Keys

A shop's own key is pinned to that shop, so requests need no merchant id. Email [email protected] with the business name and ABN to get one.

• A key is shown once. SyncPay stores only a hash, so a lost key is replaced, not recovered.
• Rotation: the new key works straight away and the old one keeps working for 24 hours.
• Revocation is immediate. Use it if a key leaks.
• Building for many shops (a platform or plugin)? You get one vendor key, send merchant_ref on every request, and each shop links your account first. See Keys and merchant links.

Quickstart

1. Check the key.
   shellCopy

   curl -sS https://api.syncpay.au/v1/auth \
     -H "Authorization: Bearer spk_test_YOUR_TEST_KEY"

   jsonCopy

   {
     "object": "auth",
     "livemode": false,
     "partner": {
       "name": "Example Shop Pty Ltd",
       "kind": "merchant"
     },
     "key": {
       "prefix": "spk_test_",
       "last4": "7c2e"
     },
     "merchant_pinned": true,
     "linked_merchants": 1
   }

2. Send the smallest valid order.
   shellCopy

   curl -sS -X POST https://api.syncpay.au/v1/transactions \
     -H "Authorization: Bearer spk_test_YOUR_TEST_KEY" \
     -H "Content-Type: application/json" \
     -d '{
     "channel": "web",
     "transaction_id": "order_10433",
     "currency": "AUD",
     "total_cents": 2500,
     "created_at": "2026-10-02T03:10:00Z",
     "lines": [
       {
         "sku": "CAP-NVY",
         "description": "Cap, navy",
         "quantity": 1,
         "unit_price_cents": 2500,
         "line_total_cents": 2500
       }
     ],
     "payments": [
       {
         "payment_id": "pay_10433_1",
         "amount_cents": 2500,
         "tender_type": "card",
         "gateway": "stripe",
         "gateway_payment_id": "pi_3Qk2mR2eZvKYlo2C0ghiJKL"
       }
     ]
   }'

3. Send a full order. Two SKUs, shipping, Apple Pay through Stripe.
   shellCopy

   curl -sS -X POST https://api.syncpay.au/v1/transactions \
     -H "Authorization: Bearer spk_test_YOUR_TEST_KEY" \
     -H "Content-Type: application/json" \
     -d '{
     "channel": "web",
     "transaction_id": "order_10432",
     "type": "order",
     "status": "completed",
     "currency": "AUD",
     "subtotal_cents": 8991,
     "gst_cents": 899,
     "shipping_cents": 990,
     "discount_cents": 0,
     "total_cents": 9890,
     "created_at": "2026-10-02T03:02:11Z",
     "completed_at": "2026-10-02T03:02:14Z",
     "order_number": "10432",
     "site_url": "https://shop.example.com",
     "customer": {
       "customer_id": "cus_5571",
       "email": "[email protected]",
       "phone": "+61400000000",
       "name": "Dana Example",
       "consent": "tos_acceptance"
     },
     "lines": [
       {
         "line_id": "1",
         "sku": "TEE-BLK-M",
         "gtin": "9300000000017",
         "description": "Organic tee, black, M",
         "quantity": 2,
         "unit_price_cents": 3200,
         "line_total_cents": 6400,
         "gst_cents": 582,
         "category": "Apparel"
       },
       {
         "line_id": "2",
         "sku": "CAP-NVY",
         "description": "Cap, navy",
         "quantity": 1,
         "unit_price_cents": 2500,
         "line_total_cents": 2500,
         "gst_cents": 227,
         "category": "Accessories"
       }
     ],
     "payments": [
       {
         "payment_id": "pay_10432_1",
         "amount_cents": 9890,
         "tender_type": "card",
         "status": "captured",
         "paid_at": "2026-10-02T03:02:14Z",
         "gateway": "stripe",
         "gateway_payment_id": "pi_3Qk2mR2eZvKYlo2C0abcDEFG",
         "payment_reference": "ch_3Qk2mR2eZvKYlo2C0xyzABC",
         "avs_result": "pass",
         "cvv_result": "pass",
         "card": {
           "last4": "4242",
           "brand": "visa",
           "entry_mode": "ecommerce",
           "funding": "credit",
           "wallet": "apple_pay"
         }
       }
     ],
     "fulfilment": {
       "method": "ship",
       "status": "unfulfilled",
       "ship_to": {
         "name": "Dana Example",
         "line1": "12 Example Street",
         "line2": "Unit 3",
         "city": "Fitzroy",
         "state": "VIC",
         "postcode": "3065",
         "country": "AU"
       }
     },
     "billing_address": {
       "name": "Dana Example",
       "line1": "12 Example Street",
       "city": "Fitzroy",
       "state": "VIC",
       "postcode": "3065",
       "country": "AU"
     }
   }'

   First time: 201 Created.

   jsonCopy

   {
     "id": "txn_0b9d4e4f8a9c6b2e5d8a917f306f1c2a",
     "object": "transaction",
     "livemode": false,
     "transaction_id": "order_10432",
     "merchant_ref": null,
     "version": 1,
     "created": true,
     "updated": false
   }

4. Add tracking when it ships. Re-send the same order with fulfilment filled in. Response: 200, version: 2.
   jsonCopy

   {
     "method": "ship",
     "status": "shipped",
     "carrier": "Australia Post",
     "service": "Parcel Post",
     "tracking_number": "33ABC1234567",
     "tracking_url": "https://auspost.com.au/mypost/track/details/33ABC1234567",
     "shipped_at": "2026-10-03T00:30:00Z",
     "ship_to": {
       "name": "Dana Example",
       "line1": "12 Example Street",
       "line2": "Unit 3",
       "city": "Fitzroy",
       "state": "VIC",
       "postcode": "3065",
       "country": "AU"
     }
   }

   jsonCopy

   {
     "id": "txn_0b9d4e4f8a9c6b2e5d8a917f306f1c2a",
     "object": "transaction",
     "livemode": false,
     "transaction_id": "order_10432",
     "merchant_ref": null,
     "version": 2,
     "created": false,
     "updated": true
   }

If the gateway route is not reachable from your network yet, the same endpoint answers at https://api.syncpay.au/functions/v1/syncpay-ingest/v1/transactions.

Website snippets

Node.js

Node 18 or later (built-in fetch). Map your own order object in toSyncPay; the field names on the left are the API's.

// Server-side only. Call this from the code that marks an order as paid,
// for example your Stripe payment_intent.succeeded webhook handler.
const SYNCPAY_URL = "https://api.syncpay.au/v1/transactions";
const SYNCPAY_KEY = process.env.SYNCPAY_KEY; // spk_test_... or spk_live_...

const cents = (dollars) => Math.round(Number(dollars) * 100);

export function toSyncPay(order) {
  return {
    channel: "web",
    transaction_id: String(order.id),
    type: "order",
    status: order.refunded ? "refunded" : "completed",
    currency: order.currency.toUpperCase(),
    total_cents: cents(order.total),
    gst_cents: cents(order.taxTotal),
    subtotal_cents: cents(order.total) - cents(order.taxTotal),
    shipping_cents: cents(order.shippingTotal),
    created_at: order.createdAt,
    completed_at: order.paidAt,
    order_number: String(order.number),
    site_url: "https://shop.example.com",
    customer: { email: order.email, name: order.customerName },
    lines: order.items.map((item, i) => ({
      line_id: String(i + 1),
      sku: item.sku,
      description: item.name,
      quantity: item.quantity,
      unit_price_cents: cents(item.unitPrice),
      line_total_cents: cents(item.lineTotal),
      gst_cents: cents(item.tax),
    })),
    payments: [{
      payment_id: order.paymentIntentId,
      amount_cents: cents(order.total),
      tender_type: "card",
      gateway: "stripe",
      gateway_payment_id: order.paymentIntentId,
      paid_at: order.paidAt,
      card: { last4: order.cardLast4, brand: order.cardBrand, entry_mode: "ecommerce" },
    }],
    ...(order.tracking && {
      fulfilment: {
        method: "ship",
        status: "shipped",
        carrier: order.tracking.carrier,
        tracking_number: order.tracking.number,
        tracking_url: order.tracking.url,
        shipped_at: order.tracking.shippedAt,
      },
    }),
  };
}

// Same body is always safe to resend, so retry on 409, 429 and 5xx.
export async function sendToSyncPay(order, attempt = 1) {
  const res = await fetch(SYNCPAY_URL, {
    method: "POST",
    headers: { Authorization: `Bearer ${SYNCPAY_KEY}`, "Content-Type": "application/json" },
    body: JSON.stringify(toSyncPay(order)),
    signal: AbortSignal.timeout(10_000),
  });
  if ((res.status === 409 || res.status === 429 || res.status >= 500) && attempt < 4) {
    const wait = Number(res.headers.get("Retry-After") ?? 2 ** attempt);
    await new Promise((r) => setTimeout(r, wait * 1000));
    return sendToSyncPay(order, attempt + 1);
  }
  const body = await res.json();
  if (!res.ok) throw new Error(`SyncPay ${res.status}: ${body.error?.type}`);
  return body; // { id, version, created, updated, ... }
}

// Later, when the parcel ships: same order, now with tracking. Version goes up.
// await sendToSyncPay({ ...order, tracking: { carrier: "Australia Post", number: "33ABC1234567", url, shippedAt } });

WooCommerce (PHP)

Hooks woocommerce_payment_complete and sends with wp_remote_post. Failed sends are retried by WP-Cron.

<?php
// WooCommerce: send each paid order to SyncPay. Put this in a small plugin or
// your theme's functions.php, and the key in wp-config.php:
//   define('SYNCPAY_KEY', 'spk_test_...');

function syncpay_cents($amount) {
    return (int) round((float) $amount * 100);
}

function syncpay_send_order($order_id, $fulfilment = null) {
    $order = wc_get_order($order_id);
    if (!$order || !defined('SYNCPAY_KEY')) {
        return;
    }

    $lines = [];
    foreach ($order->get_items() as $item_id => $item) {
        $product  = $item->get_product();
        $qty      = $item->get_quantity();
        $line_tot = syncpay_cents($item->get_total() + $item->get_total_tax());
        $lines[] = [
            'line_id'          => (string) $item_id,
            'sku'              => $product ? $product->get_sku() : null,
            'description'      => $item->get_name(),
            'quantity'         => $qty,
            'unit_price_cents' => $qty ? (int) round($line_tot / $qty) : $line_tot,
            'line_total_cents' => $line_tot,
            'gst_cents'        => syncpay_cents($item->get_total_tax()),
        ];
    }

    $total = syncpay_cents($order->get_total());
    $tax   = syncpay_cents($order->get_total_tax());
    $paid  = $order->get_date_paid();

    $body = [
        'channel'        => 'web',
        'transaction_id' => (string) $order->get_id(),
        'type'           => 'order',
        'status'         => $order->get_status() === 'refunded' ? 'refunded' : 'completed',
        'currency'       => $order->get_currency(),
        'total_cents'    => $total,
        'gst_cents'      => $tax,
        'subtotal_cents' => $total - $tax,
        'shipping_cents' => syncpay_cents($order->get_shipping_total() + $order->get_shipping_tax()),
        'discount_cents' => syncpay_cents($order->get_discount_total() + $order->get_discount_tax()),
        'created_at'     => $order->get_date_created()->format(DATE_ATOM),
        'completed_at'   => $paid ? $paid->format(DATE_ATOM) : null,
        'order_number'   => (string) $order->get_order_number(),
        'site_url'       => home_url(),
        'customer'       => [
            'email' => $order->get_billing_email(),
            'phone' => $order->get_billing_phone(),
            'name'  => trim($order->get_billing_first_name() . ' ' . $order->get_billing_last_name()),
        ],
        'lines'          => $lines,
        'payments'       => [[
            'payment_id'         => $order->get_transaction_id() ?: 'wc_' . $order->get_id(),
            'amount_cents'       => $total,
            'tender_type'        => 'card',
            'gateway'            => $order->get_payment_method(),
            'gateway_payment_id' => $order->get_transaction_id() ?: null,
            'paid_at'            => $paid ? $paid->format(DATE_ATOM) : null,
        ]],
    ];
    if ($fulfilment) {
        $body['fulfilment'] = $fulfilment;
    }

    $res = wp_remote_post('https://api.syncpay.au/v1/transactions', [
        'headers' => [
            'Authorization' => 'Bearer ' . SYNCPAY_KEY,
            'Content-Type'  => 'application/json',
        ],
        'body'    => wp_json_encode($body),
        'timeout' => 10,
    ]);
    $code = is_wp_error($res) ? 0 : wp_remote_retrieve_response_code($res);
    if ($code === 0 || $code === 409 || $code === 429 || $code >= 500) {
        // Safe to retry later with the same order: SyncPay deduplicates on transaction_id.
        $order->add_order_note('SyncPay send failed (' . $code . '), will retry.');
        wp_schedule_single_event(time() + 300, 'syncpay_retry_order', [$order_id]);
    } elseif ($code !== 200 && $code !== 201) {
        // 4xx: retrying the same body will not help. Log it and fix the mapping.
        $order->add_order_note('SyncPay rejected the order (' . $code . '): ' . wp_remote_retrieve_body($res));
    }
}

add_action('woocommerce_payment_complete', 'syncpay_send_order');
add_action('syncpay_retry_order', 'syncpay_send_order');

// When you ship, resend the order with tracking. Where the tracking number
// lives depends on your shipping plugin; this reads two example meta keys.
add_action('woocommerce_order_status_completed', function ($order_id) {
    $order = wc_get_order($order_id);
    $tracking = $order ? $order->get_meta('_tracking_number') : '';
    if (!$tracking) {
        return;
    }
    syncpay_send_order($order_id, [
        'method'          => 'ship',
        'status'          => 'shipped',
        'carrier'         => $order->get_meta('_tracking_provider') ?: null,
        'tracking_number' => $tracking,
        'shipped_at'      => gmdate(DATE_ATOM),
    ]);
});

Request

Headers: Authorization: Bearer spk_... and Content-Type: application/json. Timestamps are ISO 8601 with an offset or Z. Amounts are integer cents and never negative.

Order

Line

Payment

Payment references are what tie the receipt to the customer's card statement. Send the gateway's payment id at minimum, and any other reference you hold in payment_reference.

Fulfilment

Customer and consent

customer_id, email, phone and name are optional. Set consent to explicit_optin or tos_acceptance only when your checkout actually collected that agreement; without it, the details sit on the receipt but no customer profile is created. Shipping and billing addresses are personal information: send them only if your privacy policy covers sharing them with SyncPay.

Updates and retries

• transaction_id is the idempotency key. Always send the full, current order, not a diff.
• Same body again: 200, same version, updated: false. Retrying after a timeout or a 5xx is always safe.
• Changed body: 200, version goes up, updated: true. Use it for tracking, delivery, a cancellation (status: "voided") or a refund (status: "refunded" or "partially_refunded" with refunded_cents).

Sandbox

Same URL, spk_test_ key. Test mode runs every check (authentication, validation, card-data refusal, idempotency, versioning) and stores the order for your testing only: no receipt, nothing in the merchant dashboard, nothing to an issuer, no charge. Responses carry "livemode": false. Test orders are deleted after 30 days.

Card data

SyncPay refuses card data rather than quietly dropping it. A field named like a card number, CVV, expiry, track or PIN, or a 13 to 19 digit number that passes the Luhn check in a free-text field, gets 400 card_data_rejected. The body is not stored and not logged. Keeping card data out keeps your PCI scope and ours unchanged.

Responses and errors

Success is 201 the first time a transaction_id is seen and 200 after that. The response is the same whether or not the order ends up on a receipt.

{
  "error": {
    "type": "invalid_request",
    "message": "2 fields are invalid",
    "fields": [
      {
        "field": "lines[0].quantity",
        "message": "must be a number greater than 0"
      },
      {
        "field": "currency",
        "message": "is required"
      }
    ]
  }
}

Limits

The path carries /v1. New optional fields can appear in responses at any time, so ignore fields you do not know. Breaking changes get /v2.

Questions and keys: [email protected].