URL Guardrail

This policy provides the capability to perform URL validity checks on incoming or outgoing JSON payloads. This component acts as a guardrail to enforce content safety by validating embedded URLs for accessibility or DNS resolution.

Configure URL Guardrail

1. In the left navigation menu, click Develop, then select Policy.

2. Click the Add policy icon in the required resource → Request/Response Flow → Attach Mediation Policy.

3. Add the policy information and click Save.

The following table lists and describes the configuration parameters available for the URL Guardrail policy:

Parameter Name	Description
Guardrail Name	The name of the guardrail policy. This will be used for tracking purposes.
Perform DNS Lookup	If enabled, a DNS lookup will be performed to validate the extracted URLs. If disabled, a connection attempt will be made instead.
Connection Timeout	The connection timeout for DNS lookups or connection attempts, in milliseconds. If not specified, a default timeout will be used.
JSON Path	The JSONPath expression used to extract URLs from the payload. If not specified, the entire payload will be used for validation.
Show Guardrail Assessment	When enabled, the error response will include detailed information about the reason for the guardrail intervention.

1. Save the API and Deploy the API to apply the policy to the gateway.

Sample URL Guardrail Configuration

• Guardrail Name: URL Guardrail
• Perform DNS Lookup: false
• Connection Timeout: 5000
• JSON Path: $.messages[0].content
• Show Guardrail Assessment: true

Sample Payload to be intervened from the URL Guardrail

{
  "messages": [
    {
      "role": "user",
      "content": "Check this link: http://example.com/suspicious-link and this one: https://foo.bar.baz"
    }
  ]
}

Sample Response after URL Guardrail Intervention

{
    "code": 900514,
    "message": {
        "action": "GUARDRAIL_INTERVENED",
        "actionReason": "Violation of url validity detected.",
        "assessments": {
            "invalidUrls": [
                "http://example.com/suspicious-link",
                "https://foo.bar.baz"
            ],
            "message": "One or more URLs in the payload failed validation."
        },
        "direction": "REQUEST",
        "interveningGuardrail": "URL Guardrail"
    },
    "type": "URL_GUARDRAIL"
}