Proxy-Status: add Proxy Internal Response.

[PiotrSikora]

This is proposal to add Proxy Internal Response type that could be used to indicate that the response was generated by the intermediary (since we don't have any type that could be used in such case).

• Name: proxy_internal_response
• Description: The intermediary generated the response locally, without attempting to connect to the next hop (e.g. in response to a request to a debug endpoint terminated at the intermediary).
• Extra Parameters: None.
• Recommended HTTP status code:

PR: #806

cc @mnot

[mnot]

We already have proxy_internal_error; maybe adjust that one to suit?

[PiotrSikora]

Erm, those 2 have quite different purpose:

proxy_internal_error is Proxy-Status equivalent of 500 Internal Server Error, i.e. something is terribly broken and proxy couldn't handle the received request.

proxy_internal_response is supposed to indicate successful response generated by the proxy itself (e.g. in response to a request to a special debug URL like https://www.cloudflare.com/cdn-cgi/trace).

cc @alyssawilk

[mnot]

Got it. Merging, but we might want to look at the entire set and make sure we have enough context / prose around all of them (including this one) to make sure people understand the appropriate uses of them.