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Redirect

This destination redirects users to an external website, such as your company website.

Query parameters can be added to the URL to identify and process scans correctly. Three built-in parameters are available:

  • uid: Unique tag identifier.
  • clientTagId: Tag serial number (starting from 1 for each customer).
  • lastSeenCounter: Counter value from the most recent recorded scan, useful for anti-replay verification.

Custom key-value pairs can also be added as query parameters.

DNA Redirects​

After a DNA tag scan is verified by TagLink and the user is redirected to an external URL, TagLink can no longer directly verify scan authenticity.

To preserve authenticity and uniqueness, TagLink automatically appends a single-use signed token (tl_sig) to the destination URL.

Verification methods:

  1. Online verification through POST /api/public/redirect-signature/verify. This is the only method that guarantees uniqueness because the token is validated and consumed atomically.

  2. Offline verification using the public key obtained from GET /api/public/redirect-signature/public-key. This confirms that the token was issued by TagLink but cannot detect replay attacks or URL reuse.

Example request:

{
  "signature": "<tl_sig token>"
}

Successful verification:

{
  "valid": true,
  "tenantId": "...",
  "uid": "...",
  "counter": 123,
  "issuedAt": 1735689600
}

Already used token:

{
  "valid": false,
  "reason": "ALREADY_USED"
}

Invalid or expired token:

{
  "valid": false,
  "reason": "INVALID_SIGNATURE"
}