ESP to add a header to indicate ESP version about esp

[qiwzhang]

Yes, you can compare the HTTP headers before ESP and after.
I think ESP only add one header; JWT token payload as "user-info" (I forget the exact header name). It doens't add anything for api-key or ESP version.

[inklesspen]

Is this header added for all requests, or only for the requests where user info exists?

It would be good to add a header relaying the ESP version, imho.

[qiwzhang]

x-endpoint-api-userinfo header is only added if jwt is required and the token is successfully passed verification. This header is added in the request path to the backend.

You are suggesting adding esp-version to the response header for debugging. is that right?

[inklesspen]

Also just for general user info.

[qiwzhang]

Stackdriver structPayload log already has this info