## CLI

The CLI `mesh` command is implemented in the [cmd/mesh](../operator/cmd/mesh/)
subdirectory as a Cobra command with the following subcommands:

- [manifest](../operator/cmd/mesh/manifest.go): the manifest subcommand is used to generate, install, diff or migrate Istio manifests, it has the following subcommands:

		grep -Pv 'envoy/service/discovery/v3' |\
		grep -Pv 'envoy/extensions/wasm/' |\
		grep -Pv 'envoy/extensions/filters/(http|network)/wasm/' |\
		grep -Pv 'istio\.io/api/(annotation|label|mcp|mesh|networking|security/v1alpha1|type)' |\
		(! grep -P '^k8s.io|^sigs.k8s.io/gateway-api|cel|antlr|jwx/jwk|envoy/|istio.io/api')

go-gen:
	@mkdir -p /tmp/bin
	@PATH="${PATH}":/tmp/bin go generate ./...

    axc("Auto Export Controller")

    mcfg("Mesh Config")
    dfc("Default Revision Controller")
```

As you can see, the landscape of controllers is pretty extensive at this point.

[Service Discovery](#ServiceDiscovery) and [Config Store](#ConfigStore) were already discussed above, so do not need more explanation here.

#### Mesh Config

As ztunnel aims to transparently encrypt and route users traffic, we need a mechanism to capture all traffic entering and leaving "mesh" pods.
This is a security critical task: if the ztunnel can be bypassed, authorization policies can be bypassed.

Redirection must meet these requirements:
* All traffic *egressing* a pod in the mesh should be redirected to the node-local ztunnel on port 15001.

## Introduction

The operator uses the [IstioOperator API](https://github.com/istio/api/blob/master/operator/v1alpha1/operator.proto), which has
three main components:

- [MeshConfig](https://github.com/istio/api/blob/master/mesh/v1alpha1/config.proto) for runtime config consumed directly by Istio
control plane components.

- watches k8s resource for existing pods, so that pods that have already been started can be moved in or out of the ambient mesh.
- sends UDS events to ztunnel via a socket whenever a pod is enabled for ambient mesh (whether from CNI plugin or node watcher), instructing ztunnel to create the "tube" socket.