Customizing the http response returned from the ISTIO Authorization

[Govula_Srinivas]

Hi Team,
I am trying to customize the default http response returned from ISTIO AuthorizationPolicy for unauthorized request , But unable to intercept the request flow using Envoy filter .
istio version: 1.6.12

apiVersion: networking.istio.io/v1alpha3 kind: EnvoyFilter metadata: name: reference-oauth-impl-filter-lua namespace: reference spec: workloadSelector: labels: app: reference-oauth-impl-rest # tier: backend

configPatches:

• applyTo: HTTP_FILTER
  match:
  context: SIDECAR_INBOUND
  listener:
  filterChain:
  filter:
  name: “envoy.http_connection_manager”
  subFilter:
  name: “envoy.router”
  patch:
  operation: INSERT_FIRST
  value: # lua filter specification
  name: envoy.lua
  config:
  inlineCode: |
  function envoy_on_request(request_handle)
  – request_handle:logWarn(“Hello World”)
  end

        function envoy_on_response(response_handle)
           local status_ = response_handle:headers():get(":status")
           response_handle:logInfo("in response_handle")
           response_handle:logInfo("Status: " .. status_)
  
          if(status_ == 401 or status_ == 403 ) then
                local message_ = response_handle:body()
                local response = "{"requestId"}"
                local response_ = "{ \"ID\" : 123 " .. ", \"message\"" .. ":\"" .. message_ .. "\", \"status\"" ..":" ..status_ .."}"
                response_handle:logInfo(response_)
                response_handle:body():setBytes( response_)
                response_handle:headers():replace("content-length", response_.len())
                response_handle:headers():replace("content-type", "application/json")
          end               
        end
  

Default Behaviour :

     RBAC: access denied 

status:403 and Response Headers: content-type:text/plain

Expected:

{ message: RBAC: access denied
code: 403
x-request-id:123
}

Thanks and regards,

[Gasteizko]

Hello,

I want the same behaoviour/feature. Have you found a solution or a way to do it?

Thanks in advance.