Server-to-Server (S2S) Postback Integration

14 min

Overview

Server-to-Server (S2S) Postback integration allows advertisers to send measurement and conversion events directly to MomentScience from their server. This method provides a reliable way to track conversions without requiring client-side implementation on conversion pages.

When MomentScience sends traffic to your landing pages, we include an adpx_click_idparameter in the URL. You store this identifier with the user session, then send it back to us via postback when conversions occur.

Key Benefits

No client-side dependencies: Track conversions without JavaScript, ideal when browser-based tracking is restricted or unreliable

Multi-event attribution: Record multiple conversion actions per user session with dynamic payout values

Privacy-compliant: Meet GDPR/CCPA requirements with server-side data handling

Cross-platform support: Works with mobile apps, backend systems, and any environment that can make HTTP requests

Prerequisites

Before you begin, ensure you have:

Technical capability to capture URL parameters from incoming traffic

Server infrastructure to store click identifiers and trigger postbacks

How S2S Postback Works

MomentScience sends traffic to your landing page with adpx_click_id parameter

Your system captures the adpx_click_id and stores it with the user session

User completes an action (purchase, signup, etc.)

Your server sends a postback to MomentScience with conversion details

Integration Steps

Step 1: Capture the Click ID from Incoming Traffic

When MomentScience sends traffic to your landing page, capture the adpx_click_id parameter from the URL and store the adpx_click_id value with the user's session. The method depends on your technology stack.

The adpx_click_id must be stored reliably. If this value is lost, you won't be able to attribute conversions back to MomentScience.

Example Landing Page URL

https://yourdomain.com/landing-page?adpx_click_id=abc123def456&other_param=value

Step 2: Configure Your Postback URL

Configure your system to send postbacks to the MomentScience tracking endpoint.

Examples:

Track a measurement event

https://trk.pubtailer.com/track/?click-id={ADPX_CLICK_ID}&measurement=1&event={EVENT}

Track a payable event (CPA only)

https://trk.pubtailer.com/track/?click-id={ADPX_CLICK_ID}&measurement=1&event={EVENT}&payout={PAYOUT}

Track a payable event with sale value (ROAS)

https://trk.pubtailer.com/track/?click-id={ADPX_CLICK_ID}&measurement=1&event={EVENT}&payout={PAYOUT}&sale_amount={AMOUNT}

For the event parameter, you can use any event identifier that your offer supports. Common choices include mosci, conversion, purchase, or any custom event name.

URL Parameters Reference

Parameter	Type	Required	Description
click-id	String	Yes	The adpx_click_id value received from incoming traffic
measurement	Integer	Conditional	Must be set to 1. Required whenever you send an event, with or without a payout.
event	String	Conditional	Event type identifier (e.g., purchase, signup, conversion). Required for event-based and variable payout tracking; can be sent without payout for no-payout event tracking.
payout	Decimal	Conditional	Payout amount for the conversion in USD (e.g., 25.50). Only required when the event carries a payout, omit it for no-payout event tracking.
sale_amount	Decimal	No	Sale amount for CPS goal tracking.

Step 3: Trigger Postbacks on Conversion Events

When a user completes a conversion action, send a postback to MomentScience with the stored adpx_click_id.

Example Postback URLs

Signup Event (No Payout)

curl -X GET "https://trk.pubtailer.com/track/?click-id=abc123def456&measurement=1&event=signup" -H "Accept: /" -H "Cache-Control: no-cache"

Purchase Event with Payout

curl -X GET "https://trk.pubtailer.com/track/?click-id=abc123def456&measurement=1&event=conversion&payout=25.00" -H "Accept: /" -H "Cache-Control: no-cache"

Lead Generation

curl -X GET "https://trk.pubtailer.com/track/?click-id=abc123def456&measurement=1&event=lead&payout=5.00" -H "Accept: /"

Subscription with Payout and Sale Amount (for CPS)

curl -X GET "https://trk.pubtailer.com/track/?click-id=abc123def456&measurement=1&event=subscription&payout=29.99&sale_amount=149.99" -H "Accept: /"

Use lowercase event names with underscores (e.g., profile_complete, trial_start). Keep names descriptive but concise, avoid special characters except underscores, and limit to 50 characters maximum.

You can send multiple postbacks for the same adpx_click_id if multiple conversion events occur. For example, a user might sign up (first event) and then make a purchase (second event) within your defined conversion window.

Postback Response Codes

MomentScience returns HTTP status codes to indicate the result of your postback request:

Status Code	Meaning	Action Required
200 OK	Conversion successfully recorded	No action needed. Do not resend.
Any other status	Request failed or error occurred	Retry the request with exponential backoff

Only retry postbacks that receive a non-200 status code. If you receive a 200 OK response, the conversion has been recorded successfully and should not be sent again.

If you encounter any issues during integration or have questions about S2S postback tracking, contact us [email protected].