Available fields and functions in Rewrite URL Rules

​​ Filter expressions

A Rewrite URL Rule filter expression (that is, the expression that defines which incoming requests match the rule) can include the following fields:

• cf.edge.server_ip
• cf.edge.server_port
• cf.edge.client_port
• cf.zone.name
• cf.metal.id
• cf.ray_id
• cf.tls_client_auth.*
• http.cookie
• http.host
• http.referer
• http.request.headers
• http.request.headers.*
• http.request.accepted_languages
• http.request.method
• http.request.timestamp.sec
• http.request.timestamp.msec
• http.request.full_uri
• http.request.uri
• http.request.uri.*
• http.request.version
• raw.http.request.full_uri
• raw.http.request.uri
• raw.http.request.uri.*
• http.user_agent
• http.x_forwarded_for
• ip.src
• ip.src.lat
• ip.src.lon
• ip.src.city
• ip.geoip.*
• ssl

Refer to Fields for reference information on these fields.

For information on the available functions, refer to Functions.

The maximum length of a filter expression is 4,096 characters.

​​ Rewrite expressions

A rewrite expression (that is, the expression that defines the dynamic URL rewrite to perform) can only include the following fields:

• http.request.uri.*
• http.request.headers.*
• http.request.accepted_languages

Refer to Fields for reference information on these fields.

The concat() and regex_replace() functions can appear only once in a rewrite expression.