// Items is the list of Deployments.
  repeated Deployment items = 2;
}

// DeploymentSpec is the specification of the desired behavior of the Deployment.
message DeploymentSpec {
  // Number of desired pods. This is a pointer to distinguish between explicit
  // zero and not specified. Defaults to 1.
  // +optional
  optional int32 replicas = 1;

  // The config of this deployment rollback.
  optional RollbackConfig rollbackTo = 3;
}

// DeploymentSpec is the specification of the desired behavior of the Deployment.
message DeploymentSpec {
  // Number of desired pods. This is a pointer to distinguish between explicit
  // zero and not specified. Defaults to 1.
  // +optional
  optional int32 replicas = 1;

  // Items is the list of Deployments.
  repeated Deployment items = 2;
}

// DeploymentSpec is the specification of the desired behavior of the Deployment.
message DeploymentSpec {
  // Number of desired pods. This is a pointer to distinguish between explicit
  // zero and not specified. Defaults to 1.
  // +optional
  optional int32 replicas = 1;

  // The config of this deployment rollback.
  optional RollbackConfig rollbackTo = 3;
}

// DeploymentSpec is the specification of the desired behavior of the Deployment.
message DeploymentSpec {
  // replicas is the number of desired pods. This is a pointer to distinguish between explicit
  // zero and not specified. Defaults to 1.
  // +optional
  optional int32 replicas = 1;

Historically, Istio had to really be consumed all-or-nothing for things to work as expected.
In particular, an easy answer to "I just want to have mTLS everywhere, then I can think about adopting the rest of service mesh" was desired.

## Goals

Ztunnel should:
* **Not break users**. This means that deploying Ztunnel should retain all existing Kubernetes behavior.

  // It cannot be less that minReplicas.
  optional int32 maxReplicas = 3;

  // metrics contains the specifications for which to use to calculate the
  // desired replica count (the maximum replica count across all metrics will
  // be used).  The desired replica count is calculated multiplying the
  // ratio between the target value and the current value by the current

  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // Specification of the desired behavior of a cron job, including the schedule.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
  // +optional
  optional CronJobSpec spec = 2;

  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // `spec` is the specification of the desired behavior of a FlowSchema.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
  // +optional
  optional FlowSchemaSpec spec = 2;

  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // `spec` is the specification of the desired behavior of a FlowSchema.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
  // +optional
  optional FlowSchemaSpec spec = 2;

}

// specification of a horizontal pod autoscaler.
message HorizontalPodAutoscalerSpec {
  // reference to scaled resource; horizontal pod autoscaler will learn the current resource consumption
  // and will set the desired number of pods by using its Scale subresource.
  optional CrossVersionObjectReference scaleTargetRef = 1;

  // minReplicas is the lower limit for the number of replicas to which the autoscaler