Match Workers subrequests by upstream zone — cf.worker.upstream_zone now supported in Transform Rules
You can now use the cf.worker.upstream_zone field in Transform Rules to control rule execution based on whether a request originates from Workers, including subrequests issued by Workers in other zones.
What's new:
cf.worker.upstream_zoneis now supported in Transform Rules expressions.- Skip or apply logic conditionally when handling Workers subrequests.
For example, to add a header when the subrequest comes from another zone:
Text in Expression Editor (replace myappexample.com with your domain):
(cf.worker.upstream_zone != "" and cf.worker.upstream_zone != "myappexample.com")Selected operation under Modify request header: Set static
Header name: X-External-Workers-Subrequest
Value: 1
This gives you more granular control in how you handle incoming requests for your zone.
Learn more in the Transform Rules documentation and Rules language fields reference.