[Weighted Shard Routing] Disallow search requests with preference parameter with strict weighted shard routing

[anshu1106]

Is your feature request related to a problem? Please describe.
With weighted shard routing, requests are distributed across data nodes in the ratio the weights are assigned. Since search requests with preference parameter runs the request only on the specified nodes, this won't honour weighted shard routing.
ie for a 3 az domain with weights (1, 2, 4) preference searches on nodes with weight 1 can cause more request on nodes with weight 1.

Describe the solution you'd like
Allow support for strict weighted shard routing using cluster setting.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[anasalkouz]

@anshu1106 Are you actively working on this? can I assign it to you?

[anshu1106]

@anshu1106 Are you actively working on this? can I assign it to you?

Yes