Header rule has no effect

Networking
1

I created a rule to redirect all requests which has specified header but the rule has no effect.

My rule :

kind: VirtualService
apiVersion: networking.istio.io/v1alpha3
metadata:
  name: reviews
  namespace: spiro--bookinfo-dev
spec:
  hosts:
    - reviews
  http:
    - match:
          headers:
            version:
              exact: v1
      route:
        - destination:
            host: reviews
            subset: v1
    - match:
        - headers:
            version:
              exact: v3
      route:
        - destination:
            host: reviews
            subset: v3
    - route:
        - destination:
            host: reviews
            port:
              number: 9080

To add the header i use an EnvoyFilter :

kind: EnvoyFilter
apiVersion: networking.istio.io/v1alpha3
metadata:
  name: reviews
  namespace: spiro--bookinfo-dev
spec:
  workloadSelector:
    labels:
      app: reviews
  configPatches:
    - applyTo: HTTP_FILTER
      match:
        context: SIDECAR_INBOUND
      patch:
        operation: INSERT_BEFORE
        value:
          name: envoy.lua
          typed_config:
            '@type': type.googleapis.com/envoy.extensions.filters.http.lua.v3.Lua
            inlineCode: |
              function envoy_on_request(request_handle)
                request_handle:headers():add("version", "v1")
              end

I checked that it is added to request in istio-proxy :

headers_encoded::authority:reviews:9080&:path:/reviews/0&:method:GET&user-agent:Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:96.0) … ;URI=spiffe://cluster.local/ns/spiro–bookinfo-dev/sa/default&version:v1

Does header rule works for internal services ?

2

Looks like the header is added after routing. It works with an outbound rule :

kind: EnvoyFilter
apiVersion: networking.istio.io/v1alpha3
metadata:
  name: productpage
  namespace: spiro--bookinfo-dev
spec:
  workloadSelector:
    labels:
      app: productpage
  configPatches:
    - applyTo: HTTP_FILTER
      match:
        context: SIDECAR_OUTBOUND
      patch:
        operation: INSERT_BEFORE
        value:
          name: envoy.lua
          typed_config:
            '@type': type.googleapis.com/envoy.extensions.filters.http.lua.v3.Lua
            inlineCode: |
              function envoy_on_request(request_handle)
                request_handle:headers():add("version", "v1")
              end