This provides maximum flexibility with minimal API surface overhead.

## Making changes

## Step 1. Make changes in charts and values.yaml in `manifests` directory

Be sure to provide sufficient documentation and example usage in values.yaml.
If the chart has a `values.schema.json`, that should be updated as well.

## Step 2. Update the istioctl/Operator values

If you are modifying the `gateway` chart, you can stop here.

  //
  // The minimum valid value for expirationSeconds is 600, i.e. 10 minutes.
  //
  // +optional
  optional int32 expirationSeconds = 8;

  // allowedUsages specifies a set of usage contexts the key will be
  // valid for.
  // See:
  // 	https://tools.ietf.org/html/rfc5280#section-4.2.1.3
  // 	https://tools.ietf.org/html/rfc5280#section-4.2.1.12
  //
  // Valid values are:

```

2) `istio-cni` chart installs the CNI plugin. This should be installed after the `base` chart and prior to `istiod` chart. Need to add `--set pilot.cni.enabled=true` to the `istiod` install to enable its usage.

```console
helm install istio-cni -n kube-system manifests/charts/istio-cni --set profile=openshift
```

3) `istio-control/istio-discovery` chart installs a revision of istiod.

```console

Istio reads from over 20 different resources types, and aggregates them together to build the proxy configuration. These resources can be sourced from Kubernetes (via watches), files, or over xDS; Kubernetes is by far the most common usage, though.

Primarily for historical reasons, ingestion is split into a few components.

#### ConfigStore

  //
  // +optional
  optional bool podInfoOnMount = 2;

  // volumeLifecycleModes defines what kind of volumes this CSI volume driver supports.
  // The default if the list is empty is "Persistent", which is the usage defined by the
  // CSI specification and implemented in Kubernetes via the usual PV/PVC mechanism.
  //
  // The other mode is "Ephemeral". In this mode, volumes are defined inline inside the pod spec

// New uses of this type are discouraged because of difficulty describing its usage when embedded in APIs.
//  1. Ignored fields.  It includes many fields which are not generally honored.  For instance, ResourceVersion and FieldPath are both very rarely valid in actual usage.
//  2. Invalid usage help.  It is impossible to add specific help for individual usage.  In most embedded usages, there are particular

.PHONY: show.env show.goenv

show.env: ; $(info $(H) environment variables...)
	$(Q) printenv

show.goenv: ; $(info $(H) go environment...)
	$(Q) $(GO) version
	$(Q) $(GO) env

# show makefile variables. Usage: make show.<variable-name>
show.%: ; $(info $* $(H) $($*))
	$(Q) true

#-----------------------------------------------------------------------------
# Target: custom resource definitions

  //
  // +optional
  optional bool podInfoOnMount = 2;

  // volumeLifecycleModes defines what kind of volumes this CSI volume driver supports.
  // The default if the list is empty is "Persistent", which is the usage defined by the
  // CSI specification and implemented in Kubernetes via the usual PV/PVC mechanism.
  //
  // The other mode is "Ephemeral". In this mode, volumes are defined inline inside the pod spec

Aside from this, there are a few conveniences and workarounds built-in to the client to make things simpler.

*All Istio Kubernetes usage should use this library and not operate on Kubernetes clients directly.*

  //  4. Required, permitted, or forbidden key usages / extended key usages.
  //  5. Expiration/certificate lifetime: whether it is fixed by the signer, configurable by the admin.
  //  6. Whether or not requests for CA certificates are allowed.
  optional string signerName = 7;