In our testing, even the most generous representations give custom types a 10x edge (in size, allocations, and CPU time) over Envoy types.
In addition, they are more clear and strictly typed; using Envoy types would require us to put a lot of information in untyped `metadata` maps.

With this in mind, Ztunnel supports two xDS resources: `Address` and `Authorization`.

### Address Type

{ "avg": false, "current": false, "max": false, "min": false, "show": true, "total": false, "values": false }, "lines": true, "linewidth": 1, "links": [], "nullPointMode": "null", "percentage": false, "pointradius": 5, "points": false, "renderer": "flot", "seriesOverrides": [], "spaceLength": 10, "stack": false, "steppedLine": false, "targets": [ { "expr": "sum(istio_build{component=\"pilot\"}) by (tag)", "format": "time_series", "intervalFactor": 1, "legendFormat": "{{ tag }}", "refId": "A" } ],...

// Values should try to use sendmail-style values as in <sysexits.h>
// See e.g. https://man.openbsd.org/sysexits.3
// or `less /usr/includes/sysexits.h` if you're on Linux
//
// Picking the right range is tricky--there are a lot of reserved ones (see
// https://www.tldp.org/LDP/abs/html/exitcodes.html#EXITCODESREF) and then some
// used by convention (see sysexits).
//
// The intention here is to use 64-78 in a way that matches the attempt in

### Writing controllers

Istio provides a few helper libraries to get started writing a controller. While these libraries help, there are still a lot of subtleties in correctly writing (and testing!) a controller properly.

To get started writing a controller, review the [Example Controller](../../pkg/kube/controllers/example_test.go).

### Controllers overview

func printIngressService(writer io.Writer, initPrintNum int,
	ingress *ingressInfo,
) {
	if ingress == nil || ingress.service == nil || len(ingress.pods) == 0 {
		return
	}
	// The ingressgateway service offers a lot of ports but the pod doesn't listen to all
	// of them.  For example, it doesn't listen on 443 without additional setup.  This prints
	// the most basic output.
	portsToShow := map[string]bool{
		"http2": true,

	cmdGenerate cmdType = "istioctl manifest generate"
	// istioctl install
	cmdApply cmdType = "istioctl install"
	// in-cluster controller
	cmdController cmdType = "operator controller"
)

// Golden output files add a lot of noise to pull requests. Use a unique suffix so
// we can hide them by default. This should match one of the `linuguist-generated=true`
// lines in istio.io/istio/.gitattributes.
const (

        # - name: if-return
  unparam:
    # Inspect exported functions, default is false. Set to true if no external program/library imports your code.
    # XXX: if you enable this setting, unparam will report a lot of false-positives in text editors:
    # if it's called for subdir of a project it can't find external interfaces. All text editor integrations
    # with golangci-lint call it on a directory with the changed file.

Telemetry | Prometheus
Telemetry | Prometheus Operator
Telemetry | Grafana
Telemetry | Kiali
Telemetry | Tracing
ThirdParty | CNI

### Namespaces

The `IstioOperatorSpec` API and underlying new Helm charts offer a lot of flexibility in which namespaces features and
components are installed into. Namespace definitions can be defined and specialized at the global, feature and component

      },
      "lines": true,
      "linewidth": 1,
      "links": [],
      "nullPointMode": "null",
      "percentage": false,
      "pointradius": 5,
      "points": false,
      "renderer": "flot",
      "seriesOverrides": [],
      "spaceLength": 10,
      "stack": false,
      "steppedLine": false,
      "targets": [
        {
          "datasource": {
            "type": "prometheus",