k8s, Istio: remove transfer-encoding header - kubernetes

Question

In application's responses we see doubled transfer-encoding headers.
Suppose, because of that we get 503 in UI, but at the same time application returns 201 in pod's logs.
Except http code: 201 there are transfer-encoding=chunked and Transfer-Encoding=chunked headers in logs, so that could be a reason of 503.
We've tried to remove transfer-encoding via Istio virtual service or envoy filter, but no luck..
Here are samples we tried:
VS definition:
kind: VirtualService
apiVersion: networking.istio.io/v1alpha3
metadata:
name: test
namespace: my-ns
spec:
hosts:
- my-service
http:
- route:
- destination:
host: my-service
headers:
response:
remove:
- transfer-encoding
---
kind: VirtualService
apiVersion: networking.istio.io/v1alpha3
metadata:
name: test
namespace: istio-system
spec:
gateways:
- wildcard-api-gateway
hosts:
- my-ns_domain
http:
- match:
- uri:
prefix: /operator/api/my-service
rewrite:
uri: /my-service
route:
- destination:
host: >-
my-service.my-ns.svc.cluster.local
port:
number: 8080
headers:
response:
remove:
- transfer-encoding
EnvoyFilter definition:
apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
name: test
namespace: istio-system
spec:
configPatches:
- applyTo: HTTP_FILTER
match:
context: SIDECAR_OUTBOUND
patch:
operation: ADD
value:
name: envoy.filters.http.lua
typed_config:
"#type": "type.googleapis.com/envoy.extensions.filters.http.lua.v3.Lua"
inlineCode: |
function envoy_on_response(response_handle)
response_handle:headers():remove("transfer-encoding")
end
In older envoy versions I see envoy.reloadable_features.reject_unsupported_transfer_encodings=false was a workaround. Unfortunately, it was deprecated.
Please advise what is wrong with VS/filter or is there any alternative to reject_unsupported_transfer_encodings option?
Istio v1.8.2
Envoy v1.16.1

Answer 1

Decision so far: created requirement for dev team to remove the duplication of chunked encoding