Sklik Server-Side Google Tag Manager Template

This document provides a comprehensive overview of the Sklik server-side Google Tag Manager (GTM) template, including its configuration options, logic flow, and how it processes conversion and retargeting events.

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Overview

The Sklik GTM server-side template facilitates the sending of conversion and retargeting events to Sklik (Seznam.cz's advertising platform). It uses server-side tagging to enhance data privacy, ensure reliable event tracking, and maintain compatibility with browser restrictions.

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Key Functions

• logToConsole: Logs messages to the server-side console for debugging purposes.
• getRequestHeader: Fetches HTTP request headers.
• getEventData: Retrieves data from incoming events.
• sendPixelFromBrowser: Sends a pixel request back to the browser to preserve third-party cookies and the client’s IP address.

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Template Inputs

Conversion Inputs

• conversionId (Required): ID of the conversion event.
• conversionValue (Optional): Value associated with the conversion.
• conversionOrderId (Optional): Unique order ID for the conversion.
• conversionZboziId (Optional): ID for Zbozi.cz (disabled in current implementation).
• conversionZboziType (Optional): Type for Zbozi.cz (disabled in current implementation).

Retargeting Inputs

• retargetingId (Required): ID for the retargeting event.
• retargetingItemId (Optional): Item ID for the retargeting event.
• retargetingPageType (Optional): Type of page for the retargeting event.
• retargetingCategory (Optional): Category for the retargeting event.
• retargetingUrl (Optional): URL for the retargeting event.

Common Inputs

• tagType (Required): Specifies whether the tag is for conversion or retargeting.
• tagConsent (Required): Defines consent logic. Accepted values:
  • inherit: Consent is determined by the x-ga-gcs event data.
  • granted: Consent is explicitly granted.
  • denied: Consent is explicitly denied.

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Logic Flow

1. Initialization

• Logs the start of the template execution.
• Captures essential event data, including:
  • pageReferrer: Referring page URL.
  • consentState: Consent signal from the event data (x-ga-gcs).

2. Tag Type Handling

Depending on tagType, the script processes either a conversion or retargeting event:

Conversion

• Constructs the base URL: https://c.seznam.cz/conv?id=...
• Appends optional query parameters (e.g., value, orderId, etc.).

Retargeting

• Constructs the base URL: https://c.seznam.cz/retargeting?id=...
• Appends optional query parameters (e.g., itemId, pageType, etc.).

3. Consent Evaluation

• Evaluates the consent state based on tagConsent:
  • inherit: Uses the third character of x-ga-gcs to determine consent (1 = granted, 0 = denied, -1 = unknown).
  • granted or denied: Sets explicit consent values.
• Appends the consent flag (consent) to the destination URL.

4. Send Pixel

• Logs the final destination URL.
• Sends a pixel request to the Seznam.cz server using sendPixelFromBrowser.

5. Completion

• Calls data.gtmOnSuccess to signal successful tag execution.

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Destination URL Construction

The final URL is constructed dynamically based on input values and the tag type. Example formats:

Conversion:

https://c.seznam.cz/conv?id=&value=&orderId=&url=&consent=

Retargeting:

https://c.seznam.cz/retargeting?id=&itemId=&pageType=&url=&consent=

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Error Handling

• If any required input (e.g., conversionId or retargetingId) is missing, the script will not execute correctly, and debugging logs will indicate the issue.
• Consent state is handled gracefully, with a default value of -1 (unknown) if no valid consent signal is found.

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Debugging

• Use logToConsole messages to trace the script’s execution flow.
• Check the constructed URLs in the server logs for validation.