// used by convention (see sysexits).
//
// The intention here is to use 64-78 in a way that matches the attempt in
// sysexits to signify some error running istioctl, and use 79-125 as custom
// error codes for other info that we'd like to use to pass info on.
const (
	ExitUnknownError   = 1 // for compatibility with existing exit code
	ExitIncorrectUsage = 64
	ExitDataError      = 65 // some format error with input data

### Examples

#### Configuring mesh configuration settings

Any [Mesh Config](https://istio.io/latest/docs/reference/config/istio.mesh.v1alpha1/) options can be configured like below:

```yaml
meshConfig:
  accessLogFile: /dev/stdout
```

#### Revisions

Control plane revisions allow deploying multiple versions of the control plane in the same cluster.

{{- if ne $gateway.injectionTemplate "" }}
{{/* This provides a minimal gateway, ready to be injected.
     Any settings from values.gateways should be here - these are options specific to the gateway.
     Global settings, like the image, various env vars and volumes, etc will be injected.
     The normal Deployment is not suitable for this, as the original pod spec will override the injection template. */}}
apiVersion: apps/v1
kind: Deployment
metadata:

{{- if ne $gateway.injectionTemplate "" }}
{{/* This provides a minimal gateway, ready to be injected.
     Any settings from values.gateways should be here - these are options specific to the gateway.
     Global settings, like the image, various env vars and volumes, etc will be injected.
     The normal Deployment is not suitable for this, as the original pod spec will override the injection template. */}}
apiVersion: apps/v1
kind: Deployment
metadata:

		// these sometimes fail due to "Device or resource busy" - again NBD.
		{"-t", iptablesconstants.NAT, "-F", ChainHostPostrouting},
		{"-t", iptablesconstants.NAT, "-X", ChainHostPostrouting},
	}

	// iptablei seems like a reasonable pluralization of iptables
	iptablesVariant := []dep.IptablesVersion{}
	iptablesVariant = append(iptablesVariant, cfg.iptV)

	if cfg.cfg.EnableIPv6 {
		iptablesVariant = append(iptablesVariant, cfg.ipt6V)

func renderRecursive(manifests name.ManifestMap, installTree helmreconciler.ComponentTree, outputDir string, dryRun bool, l clog.Logger) error {
	for k, v := range installTree {
		componentName := string(k)
		// In cases (like gateways) where multiple instances can exist, concatenate the manifests and apply as one.
		ym := strings.Join(manifests[k], helm.YAMLSeparator)
		l.LogAndPrintf("Rendering: %s", componentName)

  //
  // This field is immutable.
  //
  // +optional
  optional bool attachRequired = 1;

  // podInfoOnMount indicates this CSI volume driver requires additional pod information (like podName, podUID, etc.)
  // during mount operations, if set to true.
  // If set to false, pod information will not be passed on mount.
  // Default is false.
  //

	return createDashCmd(ctx, CreateProxyDashCmdConfig{
		CommandUsage: "proxy [<type>/]<name>[.<namespace>]",
		CommandShort: "Open admin web UI for a proxy",
		CommandLong:  `Open the admin dashboard for a proxy, like envoy and ztunnel pods`,
		CommandExample: `  # Open envoy admin dashboard for the productpage-123-456.default pod
  istioctl dashboard proxy productpage-123-456.default

  // Defaults to 0644.
  // Directories within the path are not affected by this setting.
  // This might be in conflict with other options that affect the file
  // mode, like fsGroup, and the result can be other mode bits set.
  // +optional
  optional int32 defaultMode = 3;

  // optional specify whether the ConfigMap or its keys must be defined
  // +optional

```

### New API customization

The [new platform level installation API](https://github.com/istio/api/blob/master/operator/v1alpha1/operator.proto)
defines install time parameters like component and enablement and namespace, and K8s settings like resources, HPA spec etc. in a structured way.
The simplest customization is to turn components on and off. For example, to turn on cni ([samples/cni-on.yaml](samples/cni-on.yaml):

```yaml