How to add X-Kong-Upstream-Status header to response about kong-js-pdk HOT 4 OPEN

Actually, I just tried something which had an effect ... in the startup for Kong, we include this setting:

-e "KONG_HEADERS=X-Kong-Proxy-Latency, X-Kong-Response-Latency, X-Kong-Upstream-Latency, X-Kong-Upstream-Status, X-Kong-Admin-Latency" \

This is because for security reasons, we want to ensure Kong does not include the "Via" header to clients (so they don't know they are talking to Kong). My understanding about this setting is that it tells Kong which are the "legal" headers to send to a client. When I removed this from the startup, now I'm seeing the X-Kong-Upstream-Status header that my plugin is adding. But I don't understand why the other "legal" headers like X-Kong-Upstream-Latency went through OK, and what is the connection between this setting and a bespoke plugin that tried to set one of the headers.

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@sec23206 In which phase is your plugins setting the header?

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@sec23206 In which phase is your plugins setting the header?

In the response phase.

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I feel like reponse phase is the reason but haven't verified. Although as it's name suggested, response phase
is not actually what Kong is producing responses. It's more for plugins that requires to do some mutation or inspecting
of the response body. But access may just be too early for your use case. In Lua Kong you can use header_filer but they
are not part of JS PDK.

Could you print the result of await kong.service.response.getStatus() in the same phase?

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