FXM is not creating "sc_ext_contact" cookie on external site

Question

We have multisite setup on Sitecore, example www.MainsiteA.com and www.MainsiteB.com, We have installed FXM beacon javascript code into couple of external sites, Both external sites are on sub-domain of the main sites:

1. book.MainsiteA.com
2. book.MainsiteB.com

My expectation that a user visiting www.MainsiteA.com then visits book.MainsiteA.com would have the same contact id, Same for www.MainsiteB.com and book.MainsiteB.com.

The issue we are seeing that one of the external sites does not create sc_ext_contact cookie that holds the contact id of the visitor, while the other site is creating that cookie fine.

We need this cookie as we are collecting information about the user on the external sites and we need to merge that into the same contact in xDB at later stage, we would use the contact Id stored in the sc_ext_contact cookie.

Would there be any restrictions that could prevent FXM from creating the Cookie on the external site?

Thanks

Answer 1

We are able to fix this issue, though it was unique to our case, i thought it might be helpful to others who might have this problem.

In FXM js code, the following code tries to set the sc_ext_contact cookie:

cookies.set(extCookieName, resp.ContactId, { expires: new Date(Date.parse(e.ContactExpires)), path: '/' }); 

the Date.parse(e.ContactExpires) method was always returning null resulting in the cookie never being created, This was caused by custom js extension on the external site for the Date class that was not parsing the date format that sitecore was returning correctly, After accounting for that date format in the external site, the cookie was then created correctly