Allow to disable envoy server header injection

[skonto]

Changes

• Downstream users want to hide the server header. If there is no such header present in the response, by default Envoy injects its own that has the value envoy (based on the default server_name config). Envoy allows to configure when the server header is injected. Here we support only the option to prevent Envoy's header injection. In a secured environment probably this should be on by default.

/kind

Fixes #

Release Note

A new configuration option `disable-envoy-server-header` prevents Envoy server header from being injected when there is none such header in the response.

[knative-prow]

@skonto: The label(s) kind/<kind> cannot be applied, because the repository doesn't have them.

In response to this:

Changes

• Downstream users want to hide the server header. If there is no such header present in the response, by default Envoy injects its own that has the value envoy (based on the default server_name config). Envoy allows to configure when the server header is injected. Here we support only the option to prevent Envoy's header injection. In a secured environment probably this should be on by default.

/kind

Fixes #

Release Note

Docs

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.83%. Comparing base (d661174) to head (2704cbb).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1311      +/-   ##
==========================================
+ Coverage   60.69%   60.83%   +0.13%     
==========================================
  Files          24       24              
  Lines        2005     2012       +7     
==========================================
+ Hits         1217     1224       +7     
  Misses        726      726              
  Partials       62       62              

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[ReToCode]

/lgtm
/approve

[knative-prow]

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