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

The primary configuration consumed by Ztunnel is the [`Address` resource](../../pkg/workloadapi/workload.proto).

// Overhead structure represents the resource overhead associated with running a pod.
message Overhead {
  // podFixed represents the fixed resource overhead associated with running a pod.
  // +optional
  map<string, k8s.io.apimachinery.pkg.api.resource.Quantity> podFixed = 1;
}

// RuntimeClass defines a class of container runtime supported in the cluster.
// The RuntimeClass is used to determine which container runtime is used to run

  // Extra information about the requesting user.
  // See user.Info interface for details.
  // +optional
  map<string, ExtraValue> extra = 6;
}

message CertificateSigningRequestStatus {
  // Conditions applied to the request, such as approval or denial.
  // +listType=map
  // +listMapKey=type
  // +optional
  repeated CertificateSigningRequestCondition conditions = 1;

  // +optional
  optional bytes patch = 4;

  // The type of Patch. Currently we only allow "JSONPatch".
  // +optional
  optional string patchType = 5;

  // AuditAnnotations is an unstructured key value map set by remote admission controller (e.g. error=image-blacklisted).
  // MutatingAdmissionWebhook and ValidatingAdmissionWebhook admission controller will prefix the keys with

  // +optional
  // +mapType=atomic
  map<string, string> selector = 2;

  // label selector for pods that should match the replicas count. This is a serializated
  // version of both map-based and more expressive set-based selectors. This is done to
  // avoid introspection in the clients. The string will be in the same format as the
  // query-param syntax. If the target type only supports map-based selectors, both this

  optional string uid = 2;

  // The names of groups this user is a part of.
  // +optional
  repeated string groups = 3;

  // Any additional information provided by the authenticator.
  // +optional
  map<string, ExtraValue> extra = 4;

  // +optional
  repeated string group = 4;

  // Extra corresponds to the user.Info.GetExtra() method from the authenticator.  Since that is input to the authorizer
  // it needs a reflection here.
  // +optional
  map<string, ExtraValue> extra = 5;

  // UID information about the requesting user.
  // +optional
  optional string uid = 6;
}

// SubjectAccessReviewStatus
message SubjectAccessReviewStatus {

// 'f:<name>', where <name> is the name of a field in a struct, or key in a map
// 'v:<value>', where <value> is the exact json formatted value of a list item
// 'i:<index>', where <index> is position of a item in a list
// 'k:<keys>', where <keys> is a map of  a list item's key fields to their unique values
// If a key maps to an empty Fields value, the field that key represents is part of the set.
//

Pengyuan Bian <******@****.***> 1625172474 -0700

  // +optional
  map<string, k8s.io.apimachinery.pkg.api.resource.Quantity> max = 2;

  // Min usage constraints on this kind by resource name.
  // +optional
  map<string, k8s.io.apimachinery.pkg.api.resource.Quantity> min = 3;

  // Default resource requirement limit value by resource name if resource limit is omitted.
  // +optional