api: recomputeRoute field in JWT

[arkodg]

Add a field called useForRouting that signals to Envoy Gateway that the headers generated from the claims are used to make routing decisions

Internally this field will be used to
* insert a catch-all route with a 404 direct response identical to #2586 which makes sure the jwt filter with claimToHeader is applied before recomputing routing decision

• enable clear_route_cache to recompute routing decision https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/filters/http/jwt_authn/v3/config.proto#extensions-filters-http-jwt-authn-v3-jwtprovider

Relates to #2452

[arkodg]

outlining a few other alternatives

• add a similar field at top level within jwt instead of creating it within jwt.claimToHeaders , which will have the same effect internally, since these settings internally are applied at top level
• automatically enable these settings w/o an API field if jwt.claimToHeaders is set. One downside here is, enabling clearRouteCache is expensive and may impact performance. This may not be ideal for a user who wants to jwt.claimToHeaders for ratelimiting

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.33%. Comparing base (fc7d6bc) to head (bc439f0).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Files         119      119           
  Lines       19211    19211           
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  Misses       6244     6244           
  Partials      799      799           

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[shawnh2]

lgtm

[yuluo-yx]

LGTM!

[arkodg]

ptal @guydc @zhaohuabing, I've limited the use of the field to only recalculate route, and not add a fallback/catch-all route,
we can use docs to add that manually

[arkodg]

also looking at advice on API field naming, this is what ChatGPT said

Here are some alternate API field names for recomputeRoute:

calculateRoute
updateRoute
computeNewRoute
refreshRoute
recalculateRoute

[guydc]

+1 to updateRoute

[guydc]

Do we need to state something about the impact on other features? e.g. filters that fired prior to jwt (CORS, ExtAuth, Basic, ...) will only execute in the context of the initial match. Also, later filters (Fault, RL, ...) will only execute in the context of the new route.

[arkodg]

added a comment around this

[zhaohuabing]

recomputeRoute sounds good to me, "updateRoute" is a bit ambiguous.

[zhaohuabing]

LGTM. Thanks!