type: string
                                http1MaxPendingRequests:
                                  description: Maximum number of requests that will
                                    be queued while waiting for a ready connection
                                    pool connection.
                                  format: int32
                                  type: integer

h2UpgradePolicy: description: Specify if http1.1 connection should be upgraded to http2 for the associated destination. enum: - DEFAULT - DO_NOT_UPGRADE - UPGRADE type: string http1MaxPendingReque: description: Maximum number of requests that will be queued while waiting for a ready connection pool connection. format: int32 type: integer http2MaxRequests: description: Maximum number of active requests to a destination. format: int32 type: integer idleTimeout: description: The idle timeout for upstream...

Construction should create informers (via `kclient.New`), setup a queue (via `controllers.NewQueue`), and register event handlers on the informers.
Often, these handlers are adding something to the queue like `client.AddEventHandler(controllers.ObjectHandler(queue.AddObject))`.
Construction should NOT actually start running all of these things, do I/O, or block in anyway.

}

// LimitResponse defines how to handle requests that can not be executed right now.
// +union
message LimitResponse {
  // `type` is "Queue" or "Reject".
  // "Queue" means that requests that can not be executed upon arrival
  // are held in a queue until they can be executed or a queuing limit
  // is reached.
  // "Reject" means that requests that can not be executed upon arrival
  // are rejected.

}

// LimitResponse defines how to handle requests that can not be executed right now.
// +union
message LimitResponse {
  // `type` is "Queue" or "Reject".
  // "Queue" means that requests that can not be executed upon arrival
  // are held in a queue until they can be executed or a queuing limit
  // is reached.
  // "Reject" means that requests that can not be executed upon arrival
  // are rejected.

  // +optional
  optional string apiVersion = 3;
}

// ExternalMetricSource indicates how to scale on a metric not associated with
// any Kubernetes object (for example length of queue in cloud
// messaging service, or QPS from loadbalancer running outside of cluster).
message ExternalMetricSource {
  // metric identifies the target metric by name and selector
  optional MetricIdentifier metric = 1;

  // +optional
  optional string apiVersion = 3;
}

// ExternalMetricSource indicates how to scale on a metric not associated with
// any Kubernetes object (for example length of queue in cloud
// messaging service, or QPS from loadbalancer running outside of cluster).
message ExternalMetricSource {
  // metricName is the name of the metric in question.
  optional string metricName = 1;

/pkg/kube/                                                       @istio/wg-networking-maintainers
/pkg/mcp/                                                        @istio/wg-networking-maintainers
/pkg/queue/                                                      @istio/wg-networking-maintainers
/pkg/security/                                                   @istio/wg-security-maintainers @istio/wg-environments-maintainers