[FEATURE] GlobalTrafficPolicy differentiation by URI (Request Path)

[thinkin]

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for example，where app A access app B（A us-east to B us-east，A us-west to B us-west ），but now i find flow (url prefix=/api/v1) has problem，i want to shifting app A 50% in us-east to B us-west（but only affect flow which url's prefix eq /api/v1 ）,how to achieve by GlobalTrafficPolicy?
thanks!

[aattuluri]

@thinkin Locality load balancing in istio is currently supported at a host level (its configurable on DestinationRule). Supporting the behavior at a route level would need some sophisticated configuration to create east and west specific endpoints (service entries?) and then using Istio VirtualService to shift traffic. I don't think this specific use case can be supported at the moment in admiral without native Istio support.

Also, what you are testing above is a blue/green deployment (see argo rollouts, we are adding support in admiral for rollouts in admiral v1.0 release) meaning you can use same region to test what you want do not need to mix locality into this testing, because I don't see why /api/v1 would fail in west and not other APIs? Let me know your thoughts.

[thinkin]

@aattuluri

because I don't see why /api/v1 would fail in west and not other APIs? Let me know your thoughts.

for example, router module which controls entrance traffic；

[benchi]

We would like to see some more interest from other folks before prioritizing.