Backport of feat(ingress gateway: support configuring limits in ingress-gateway c… into release/1.12.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #14749 to be assessed for backporting due to the inclusion of the label backport/1.12.

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The below text is copied from the body of the original PR.

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Description

As a user of ingress gateway, I want to increase the max_connections of the service in the ingress-gateway config entry (link to the detailed description). However, in current implementation, max_coonections can’t be changed and is set to the default value of 1024 by envoy.

This PR adds a new field named Defaults to the ingress-gateway config entry and max_xyz to individual listening services. The new fields allow user to configure the max_xyz of the upstream cluster of a specified service behind the ingress gateway.

• updated unit test and integration test
• updated external-facing doc

Testing & Reproduction steps

• A full example is verified in the integration test (test/integration/connect/envoy/case-ingress-gateway-multiple-services/config_entries.hcl).

Kind = "ingress-gateway"
Name = "my-ingress-gateway"

Defaults {
    MaxConnections = 2048          // <----- increase the max_connections of all upstream service instances
}
Listeners = [
 {
   Port = 8082
   Protocol = "http"
   Services = [
     {
        Name = "counting"
        Hosts = ["*"]
        MaxConnections = 5120          // <----- increase the max_connections, overwrite the value in Defaults
     },
     {
       Name = "counting-v2"
       Hosts = ["v2"]
     }
   ]
 }
]

• envoy cluster

counting.default.dc2.internal.ca9229ae-1b1d-af9d-47fa-43885f09557a.consul::default_priority::max_connections::5120
counting.default.dc2.internal.ca9229ae-1b1d-af9d-47fa-43885f09557a.consul::default_priority::max_pending_requests::1024
counting.default.dc2.internal.ca9229ae-1b1d-af9d-47fa-43885f09557a.consul::default_priority::max_requests::1024
counting.default.dc2.internal.ca9229ae-1b1d-af9d-47fa-43885f09557a.consul::default_priority::max_retries::3

Links

Address #13374
Supersede #14708

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PR Checklist

• updated test coverage
• external facing docs updated
• not a security concern

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Overview of commits

• 7aa0fa9 - a61b169 - 42ab367 - 2a2c275 - d896381 - accdb00 - 6134f3f - 52c2dd6

[hashicorp-cla]

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