appendVisitorIDsTo (Cross-Domain Tracking)
This function lets you share a visitor's Experience Cloud ID across domains when browsers block third-party cookies. To use this function, you must have implemented the ID service and own the source and destination domains. Available in VisitorAPI.js version 1.7.0 or higher.
- Track Visitors Across Domains When Browsers Block Third-Party Cookies
- Append Visitor ID Code Sample
- Dynamic Tag Management (DTM) and SDK Support
Track Visitors Across Domains When Browsers Block Third-Party Cookies
ID service writes a first- and third-party cookie to the browser when a person visit your site (see Cookies and the Experience Cloud Identity Service ). The first-party cookie contains the MID, a unique ID for that visitor. The third-party cookie contains another ID used by the ID service to generate the MID. When a browser blocks this third-party cookie, the ID service cannot:
- Regenerate the unique ID for that site visitor when they navigate to another domain.
- Track visitors across different domains owned by your organization.
To help solve this problem, implement Visitor.appendVisitorIDsTo( * url *) . This property lets the ID service track site visitors across multiple domains even when their browsers block third-party cookies. It works like this:
- As a visitor browses to your other domains, the Visitor.appendVisitorIDsTo( * url *) appends the MID as a query parameter in the URL redirect from the original domain to the destination domain.
- The ID service code on the destination domain extracts the MID from the URL instead of sending a request to Adobe for that visitor's ID. This request includes the third-party cookie ID, which is not available in this case.
- The ID service code on the destination page uses the passed-in MID to track the visitor.
See the code sample for details.
Append Visitor ID Code Sample
//Code on Domain A var destinationURL = "www.destination.com"; //Call the ID service var visitor = Visitor.getInstance(...); //Append visitor IDs to the destination URL var destinationURLWithVisitorIDs = visitor.appendVisitorIDsTo(destinationURL); //Result of appendVisitorIDsTo includes destination URL, Experience Cloud ID (MCMID), and Analytics ID (MCAID) "www.destination.com?adobe_mc=MCMID=1234|MCAID=5678" //Redirect to the destination