Custom / server setup

For stores on your own stack. Two jobs: keep the click ID through checkout, then call the postback from your server.

1. Capture the click ID

Set your landing URL to https://yoursite.com/?s2s_click={click_id}. When the visitor arrives, read s2s_click from the query string and store it in a first-party cookie (30 days is typical) or in their session.

2. Save it with the order

At checkout, copy the stored value onto the order record, for example in an s2s_click column. That lets you send the postback later, even from a background job.

3. Call the postback

Send a GET (or POST) from your server once the order is paid. Don't send it from the browser.

cURL

curl "https://affn.io/api/public/postback?click_id=CLICK_ID&amount=125.00&order_id=1001&sku=SHOE-1"

Node.js

// After the order is paid
const res = await fetch(`https://affn.io/api/public/postback?${new URLSearchParams({ click_id: order.s2sClick, amount: String(order.total), order_id: order.id })}`);
if (res.status !== 200 && res.status !== 409) {
  // retry later (queue / cron) – 409 means already recorded
}

PHP

$url = 'https://affn.io/api/public/postback?' . http_build_query(['click_id' => $order->s2s_click, 'amount' => $order->total, 'order_id' => $order->id]);
$ch = curl_init($url);
curl_setopt_array($ch, [CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 10]);
curl_exec($ch);
$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);

Python

import requests
r = requests.get("https://affn.io/api/public/postback", params={"click_id": order.s2s_click, "amount": order.total, "order_id": order.id}, timeout=10)
if r.status_code not in (200, 409):
    schedule_retry(order.id)

Parameters

click_id (required): the value you captured.
amount (optional): order total in USD, used for percent commissions. Also accepts sku, order_id, event=lead, and payout to set the commission directly.
status (optional): pending to hold the sale for review. The default is approved.

Responses

200: recorded. Body: {"success":true}
400: missing or invalid click_id or amount. Fix the request; don't retry as-is.
404: unknown click_id. Usually a typo or a test value.
409: already recorded. Safe to treat as success.
5xx: temporary problem. Retry with backoff.

Test your setup

Landing on your site with ?s2s_click=… stores the value
A test order saves s2s_click on the order record
Your server logs a 200 from the postback
The conversion appears under Conversions in AFFN