Rate limiter based on HTTP method question

Networking
1

Small question regarding using local_rate_limiter in my Kubernetes (1.18) cluster + Istio 1.8.x

few points:

  1. I want to avoid installing a redis image in my cluster
  2. I use istio and several have hundreds of Istio’s VirtualServices (its a special single tenant setup). Ofcourse, each one has a matching K8s service.
  3. I want to use headers query rate limiter as I allow more reads than writes for my application.
  4. I can also use port as I know my application is listening on port 8000

so now need to choose between ROUTE_CONFIGURATION or patching HTTP_ROUTE . not sure which is more suitable and more efficient for my needs.
HTTP_ROUTE seems to be the best choice

I was able to achieve simple port level rate limiter to work but still fighting the POST/GET separation.
what am I missing here

apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
  name: local-ratelimit-envoy-filter
  namespace: istio-system
spec:
  workloadSelector:
    labels:
      app: my_app_label
  configPatches:
    - applyTo: HTTP_FILTER
      listener:
        filterChain:
          filter:
            name: "envoy.filters.network.http_connection_manager"
      patch:
        operation: INSERT_BEFORE
        value:
          name: envoy.filters.http.local_ratelimit
          typed_config:
            "@type": type.googleapis.com/udpa.type.v1.TypedStruct
            type_url: type.googleapis.com/envoy.extensions.filters.http.local_ratelimit.v3.LocalRateLimit
            value:
              stat_prefix: http_local_rate_limiter
    - applyTo: HTTP_ROUTE
      match:
        context: SIDECAR_INBOUND
        routeConfiguration:
          vhost:
            name: "inbound|http|8000"
            route:
              action: ANY
      patch:
        operation: MERGE
        value:
          typed_per_filter_config:
            envoy.filters.http.local_ratelimit:
              "@type": type.googleapis.com/udpa.type.v1.TypedStruct
              type_url: type.googleapis.com/envoy.extensions.filters.http.local_ratelimit.v3.LocalRateLimit
              value:
                stat_prefix: http_local_rate_limiter
                token_bucket:
                  max_tokens: 3
                  tokens_per_fill: 3
                  fill_interval: 60s
                filter_enabled:
                  runtime_key: local_rate_limit_enabled
                  default_value:
                    numerator: 100
                    denominator: HUNDRED
                filter_enforced:
                  runtime_key: local_rate_limit_enforced
                  default_value:
                    numerator: 100
                    denominator: HUNDRED
                response_headers_to_add:
                  - append: false
                    header:
                      key: x-local-rate-limit
                      value: 'true'