Edge Rules support dynamic variables that automatically adapt based on request data. These variables allow you to create flexible rules for redirects, header modifications, and origin changes.
Supported actions
Variable expansion works in the following Edge Rule actions:
- Redirect to URL
- Change Origin URL
- Set Request Header
- Set Response Header
Variable syntax
There are two variable syntaxes available:
| Syntax | Format | Example |
|---|
| Basic | {{variable}} | {{path}} |
| Advanced | %{Collection.Key} | %{User.CountryCode} |
The {{ variable }} syntax automatically includes slashes where needed in
URLs. When using %{Collection.Key} syntax, you need to manually include
slashes in your URLs.
Basic variables
These simple variables are commonly used for general redirection and header logic:
| Variable | Description | Example Output |
|---|
{{path}} | Full request path including query string | /videos/test.mp4?user=1 |
{{hostname}} | The hostname from the request | test.b-cdn.net |
{{country_code}} | Two-letter country code of the user’s IP | US |
{{query_string}} | Query string only (without the ?) | user=1 |
{{request_method}} | HTTP method used | GET, POST |
{{file_name}} | Filename from the URL (last part after /) | file.jpg, test.mp4 |
Example: Redirect preserving path
To redirect all requests from one domain to another while preserving the path:
| Setting | Value |
|---|
| Action | Redirect to URL |
| Redirect URL | https://www.example.com{{path}} |
| Status Code | 301 |
Advanced variable collections
The advanced variable system provides detailed access to request data using the %{Collection.Key} syntax.
Access headers from the incoming HTTP request.
| Example | Result |
|---|
%{RequestHeaders.Host} | videos.example.com |
%{RequestHeaders.User-Agent} | Browser or client info |
Query
Access specific query parameters from the URL.
For a URL like /video.mp4?user=123:
| Variable | Result |
|---|
%{Query.user} | 123 |
Replace KeyName with your actual query parameter name. For example, if your
query is ?Myhash=123, use %{Query.Myhash} to get 123.
Path
Extract specific segments of the URL path. This is useful for complex routing or origin overrides.
For the example path /hello/world/bunny/eat/carrot.jpg:
| Variable | Output | Description |
|---|
%{Path.0} | hello | First segment |
%{Path.1} | world | Second segment |
%{Path.0-2} | hello/world/bunny | Range from index 0 to 2 |
%{Path.1-3} | world/bunny/eat | Range from index 1 to 3 |
%{Path.3-} | eat/carrot.jpg | From index 3 to end |
%{Path.1-} | world/bunny/eat/carrot.jpg | From index 1 to end |
%{Path.-1} | hello/world | From start up to (but not including) index 1 |
If the URL includes a query string and the path you extract doesn’t alter the filename, the query string remains intact. For example, with /hello/world/bunny/eat/carrot.jpg?query=something, using %{Path.1-} returns world/bunny/eat/carrot.jpg?query=something.
Url
Access parsed components of the full URL.
| Variable | Description | Example |
|---|
%{Url.Filename} | Last part of URL (empty for folders) | video.mp4 |
%{Url.Extension} | File extension | mp4 |
%{Url.Directory} | Folder path only | /videos/2024/ |
%{Url.Hostname} | Hostname from request | cdn.mysite.com |
%{Url.Path} | Full path and query | /videos/video.mp4?x=1 |
User
Information about the user making the request.
| Variable | Description | Example |
|---|
%{User.IP} | End-user IP address | 203.0.113.10 |
%{User.CountryCode} | Country of the request | DE |
Server
Internal information about the server processing the request.
| Variable | Description | Example |
|---|
%{Server.ZoneCode} | Code of the serving zone | NY |
%{Server.ID} | Server ID | 9482 |
Request
Information about the HTTP request.
| Variable | Description | Example |
|---|
%{Request.Method} | HTTP method | GET, POST |
%{Request.Path} | Full URL path and query | /videos/video.mp4?x=1 |
%{Request.QueryString} | Query string only | x=1 |
Practical examples
Redirect non-www to www
Redirect all requests from domain.com to www.domain.com while preserving the path:
| Setting | Value |
|---|
| Action | Redirect to URL |
| Redirect URL | https://www.domain.com{{path}} |
| Status Code | 301 |
| Condition | Request URL |
| Condition Value | * |
This rule must be added to the pull zone where domain.com is declared, not where www.domain.com is declared.If both hostnames are in the same pull zone, narrow the condition to *://domain.com* to only match the non-www version.
Route requests based on path segment
Route requests to different origins based on the first path segment:
| Setting | Value |
|---|
| Action | Change Origin URL |
| Origin URL | https://%{Path.0}.example-backend.com/%{Path.1-} |
| Condition | Request URL |
| Condition Value | */api/* |
/api/users/123 to https://api.example-backend.com/users/123.
Pass the user’s country to your origin for geo-based logic:
| Setting | Value |
|---|
| Action | Set Request Header |
| Header Name | X-User-Country |
| Header Value | %{User.CountryCode} |
| Condition | Request URL |
| Condition Value | * |
