Expression validation
The Cloudflare Filters API supports an endpoint for validating expressions.
| Operation | Method + Endpoint | Notes |
|---|---|---|
| Validate expression via query string ( ?expression=) | GET /filters/validate-expr | Allows testing and validating expressions without changing your configuration. |
| Validate expression via JSON object | POST /filters/validate-expr | Allows testing and validating expressions without changing your configuration. |
Examples
Validate expression via query string
Requestcurl "https://api.cloudflare.com/client/v4/filters/validate-expr?expression=ip.src==34" \
--header "X-Auth-Email: <EMAIL>" \
--header "X-Auth-Key: <API_KEY>"
Response{ "result": null, "success": false, "errors": [ { "message": "Filter parsing error:\n`ip.src==34`\n ^^ couldn't parse address in network: invalid IP address syntax\n" } ], "messages": null
}
Note the validation error in the response. In this example, the error is due to an invalid IP address format:
Filter parsing error:`ip.src==34` ^^ couldn't parse address in network: invalid IP address syntax Validate expression via JSON object
Requestcurl "https://api.cloudflare.com/client/v4/filters/validate-expr" \
--header "X-Auth-Email: <EMAIL>" \
--header "X-Auth-Key: <API_KEY>" \
--header "Content-Type: application/json" \
--data '{ "expression": "ip.src in {2400:cb00::/32 2405:8100::/2000 2c0f:f248::/32 2a06:98c0::/29}"}'
Response{ "result": null, "success": false, "errors": [ { "message": "Filter parsing error:\n`ip.src in {2400:cb00::/32 2405:8100::/2000 2c0f:f248::/32 2a06:98c0::/29}`\n ^^^^ number too large to fit in target type while parsing with radix 10\n" } ], "messages": null
}
Note the validation error in the response. In this example, the value for the subnet mask, /2000, is not a valid IPv6 CIDR mask:
Filter parsing error:`ip.src in {2400:cb00::/32 2405:8100::/2000 2c0f:f248::/32 2a06:98c0::/29}` ^^^^ number too large to fit in target type while parsing with radix 10