Integrate Seers’ Server-Side Tagging with Google Floodlight

This guide walks you through setting up Google Floodlight Counter and Google Floodlight Sales tags using a server-side Google Tag Manager container provisioned by Seers. By the end of this guide, your server-side container will be tracking both non-transactional user actions and transactional conversions through Campaign Manager 360. 

Prerequisites 

Before getting started, make sure the following are in place:

• Google Floodlight (Campaign Manager 360): Access to a Campaign Manager 360 account. You will need this to retrieve your Floodlight IDs and to test conversion events.
• Web Google Tag Manager (GTM): A web GTM container already deployed on your website and configured to send GA4 events to your server-side GTM instance. Refer to Google's documentation on sharing GTM container access.
• Server-Side GTM Container (Seers): A server-side GTM container provisioned by Seers, accessible via a first-party endpoint, and configured to process GA4 events. Visit the Seers Get Started guide for setup instructions.

Why Use Server-Side Tagging with Google Floodlight?

Greater Data Accuracy

Server-side tagging routes data through your own server rather than the user's browser, bypassing ad blockers and browser privacy restrictions such as ITP and ETP. This results in more complete and reliable Floodlight conversion data reaching Campaign Manager 360.

Improved Website Performance

Rather than loading and executing multiple tracking scripts in the user's browser, your website only needs to send a single lightweight data stream, such as a GA4 event, to your Seers server-side GTM endpoint. The server then handles forwarding the conversion to Floodlight and any other platforms. This dramatically reduces the number of HTTP requests and scripts running in the browser, resulting in faster page load times and a better user experience.

Enhanced Data Control

You have full control over what data is shared with Google. This allows you to enrich, filter, or anonymise information as required to comply with privacy regulations such as GDPR and CCPA. Moving tagging server-side also reduces the JavaScript load on the browser's main thread, which can improve Core Web Vitals and positively impact SEO performance.

Implementation Overview

The setup involves creating three tags: a Conversion Linker tag, a Floodlight Counter tag, and a Floodlight Sales tag.

• Conversion Linker Tag: This tag is essential for linking ad clicks to subsequent conversions. It works by detecting ad click data in your landing page URLs and storing it in a first-party cookie on your server's domain. This ensures accurate conversion attribution even in browsers that restrict third-party cookies. It must be configured to fire on every page.
• Floodlight Counter Tag: This tag measures non-transactional user actions, such as page views, newsletter sign-ups, or form submissions. It counts how many times a user completes a specific action after clicking one of your ads. You can configure it to count every occurrence, once per user, or once per user per session, depending on your measurement objective.
•  Floodlight Sales Tag: This tag is designed for transactional events such as purchases. It captures not just the conversion itself, but also dynamic data, including revenue, order ID, and the number of items sold. This enables you to measure the monetary value of your conversions and evaluate how effectively your campaigns drive sales.

Together, these three tags capture a complete user journey. The Conversion Linker preserves the ad click ID throughout the session, the Counter tag records non-transactional engagement, and the Sales tag reports transaction outcomes back to Floodlight.

Step 1: Set Up the Conversion Linker Tag

1. In your server-side GTM container, go to Tags in the left-hand navigation and click New.
2. From the list of built-in tag types, select Conversion Linker.
3. Choose from the following optional settings as needed for your setup:

• Accept Incoming Linker Parameters (Optional): This setting instructs the server-side tag to detect and process linker parameters, such like_gl, from incoming URLs. Enable this option when your user journey spans multiple domains, and you need to carry ad click data between sites for accurate cross-domain attribution. If your setup is single-domain only, this can be left unchecked.
• Override Cookie Settings (Advanced, Optional): This option gives you direct control over the name, domain, and path of the first-party cookie the tag creates. Only use this for specific, advanced scenarios, such as resolving cookie naming conflicts or restricting a cookie's scope to a particular subdomain. For most implementations, the default settings are appropriate.

4. Set up the trigger. The Conversion Linker must fire on every incoming request that could contain ad click information. The recommended approach is to use an All Pages trigger (or its equivalent) in the server container, so the tag runs on all page view events.
5. Give the tag a clear, descriptive name, for example, "Conversion Linker - Server-side", and click Save.

Step 2: Retrieve Your Floodlight Identifiers

To configure the Floodlight Counter and Sales tags, you will need three identifiers from your Campaign Manager 360 account: the Advertiser ID, the Group Tag String, and the Activity Tag String.

If you already have Google Floodlight tags in your web GTM container that you are migrating to server-side, you can use the Advertiser ID, Group Tag String, and Activity Tag String from those existing tags.

If you do not have existing Floodlight tags, log in to your Campaign Manager 360 account and open the Floodlight Activities tab. You will find the following:

• Advertiser ID (src): A unique numeric value assigned to your advertiser account. It is displayed prominently on the advertiser's main page, typically just below the advertiser's name. This is a high-level identifier that applies to all your Floodlight tags.
• Group Tag String (type): A string used to group related Floodlight activities together for reporting purposes. You will find this in the Group tag string column of the Floodlight Activities table. When creating a new Floodlight activity, you either select an existing group or create a new one; each group is assigned a unique tag string.
• Activity Tag String (cat): The specific identifier for the individual conversion event you are tracking, for example, purchase, lead_form, or signup. This is the most granular identifier for a single Floodlight tag and can be found in the Activity tag string column of the table.

If you want to quickly see all three parameters together, you can inspect an existing Floodlight tag. The three parameters are clearly labelled within the tag's URL as src, type, and cat and are separated by a semicolon. For example: In this example: - 1234567 is your Advertiser ID (src). - xyz-group is your Group Tag String (type). - purchase is your Activity Tag String (cat).

Step 3: Set Up the Google Floodlight Counter Tag

1. In your server-side GTM workspace, go to Tags and click New. Select the Floodlight Counter tag type.
2. Enter the Advertiser ID, Group Tag String, and Activity Tag String you retrieved from Campaign Manager 360 in Step 2.
3. Select the appropriate counting method based on your tracking objective:

• Standard: Counts every conversion, regardless of whether it is from the same user.
• Unique: Counts only one conversion per user.
• Per Session: Counts one conversion per user per session.

4. Configure Custom Variables (Optional). If you have custom u-variables defined in Campaign Manager 360, for example, a user's sign-up status, you will need to map them in the tag configuration. For each custom variable, create a new Event Data Variable in your server-side GTM container and link it to the corresponding u-variable field in the tag.
5. Set the trigger. Create a Custom Event trigger that fires when the specific event you want to track is received by your server-side GTM container, for example, newsletter_signup.
6. Give the tag a descriptive name and click Save.

Step 4: Set Up the Google Floodlight Sales Tag

1. In your server-side GTM workspace, go to Tags and click New. Select the Floodlight Sales tag type.
2. Enter the same Advertiser ID, Group Tag String, and Activity Tag String from Campaign Manager 360 that apply to this conversion event.
3. Map the required dynamic variables. This is the most important step for the Sales tag. You must map the Revenue and Order ID fields to the event data being passed from your client-side container:

• Revenue: Map this to an Event Data Variable that reads the transaction value, for example, {{Event Data.value}}.
• Order ID: Map this to an Event Data Variable that reads the transaction identifier, for example, {{Event Data.transaction_id}}.

4. Configure Custom Variables (Optional). If you need to send additional data, such as a promotional code or product details, you can use custom u-variables and map them from your event data. For complex data structures such as product lists, you may need to create a Custom JavaScript Variable to format the data into a single comma-separated string before assigning it to a u-variable.
5. Set the trigger. Create a Custom Event trigger that fires specifically when a purchase event is received by your server-side GTM container.
6. Give the tag a descriptive name and click Save.

Step 5: Testing, Debugging, and Publishing

Before publishing your changes, use the server-side GTM Preview Mode to thoroughly test each tag. Verify that:

• Each tag fires at the correct point in the user journey.
• The Floodlight Counter tag fires on the appropriate non-transactional event.
• The Floodlight Sales tag fires on the purchase event and includes accurate revenue and order ID values.
• The Conversion Linker tag fires on all pages.
• No unexpected errors or data discrepancies are present in the outgoing requests.

Running these checks proactively prevents data discrepancies and ensures your campaign measurement is accurate from the moment the tags go live. Once you are satisfied with the behaviour in Preview Mode, publish your workspace to deploy the changes.