TIS0802 - REMOVE Operation Ignored for applyTo Set to ROUTE_CONFIGURATION or HTTP_ROUTE

The REMOVE operation will be ignored when applyTo is set to ROUTE_CONFIGURATION or HTTP_ROUTE.

Recommendation: Ensure REMOVE Operation is Used with Compatible applyTo Values

To prevent configuration errors, either remove the REMOVE operation when applyTo is set to ROUTE_CONFIGURATION or HTTP_ROUTE, or change applyTo to a compatible value, such as CLUSTER.

Examples

1. Incorrect REMOVE Operation with applyTo Field

   apiVersion: networking.istio.io/v1alpha3
   kind: EnvoyFilter
   metadata:
     name: invalid-remove-operation
     namespace: example-namespace
   spec:
     configPatches:
     - applyTo: ROUTE_CONFIGURATION
       match:
         context: GATEWAY
       patch:
         operation: REMOVE

   Explanation: The EnvoyFilter specifies a REMOVE operation with applyTo set to ROUTE_CONFIGURATION, but the REMOVE operation is not valid for ROUTE_CONFIGURATION or HTTP_ROUTE. As a result, the configuration will be ignored.

Recommendation

Remove the REMOVE operation or change the applyTo field to a valid value.

1. Remove the REMOVE Operation

   If removing the configuration is not necessary, delete the REMOVE operation to ensure the configuration is valid.

   apiVersion: networking.istio.io/v1alpha3
   kind: EnvoyFilter
   metadata:
     name: corrected-operation
     namespace: example-namespace
   spec:
     configPatches:
     - applyTo: ROUTE_CONFIGURATION
       match:
         context: GATEWAY
       patch:
         operation: MERGE
         value:
           name: "existing-route-config"

   Explanation: By changing the operation from REMOVE to MERGE, the configuration is now valid for applyTo: ROUTE_CONFIGURATION.

2. Change applyTo to a Valid Value for REMOVE

   If the intention is to remove an existing configuration, change the applyTo field to a value that supports the REMOVE operation.

   apiVersion: networking.istio.io/v1alpha3
   kind: EnvoyFilter
   metadata:
     name: remove-operation-corrected
     namespace: example-namespace
   spec:
     configPatches:
     - applyTo: CLUSTER
       match:
         context: SIDECAR_OUTBOUND
       patch:
         operation: REMOVE

   Explanation: Changing applyTo to CLUSTER allows the REMOVE operation to be used, as removing clusters is a valid action for this applyTo value.