// scaleTargetRef points to the target resource to scale, and is used to the pods for which metrics
  // should be collected, as well as to actually change the replica count.
  optional CrossVersionObjectReference scaleTargetRef = 1;

  // minReplicas is the lower limit for the number of replicas to which the autoscaler
  // can scale down.  It defaults to 1 pod.  minReplicas is allowed to be 0 if the

  // ---
  // TODO: Update this to follow our convention for oneOf, whatever we decide it
  // to be.
  // +optional
  optional RollingUpdateDeployment rollingUpdate = 2;
}

// DEPRECATED.
message RollbackConfig {
  // The revision to rollback to. If set to 0, rollback to the last revision.
  // +optional
  optional int64 revision = 1;
}

// Spec to control the desired behavior of rolling update.

// ContainerResourceMetricSource indicates how to scale on a resource metric known to
// Kubernetes, as specified in the requests and limits, describing a single container in
// each of the pods of the current scale target(e.g. CPU or memory). The values will be
// averaged together before being compared to the target. Such metrics are built into
// Kubernetes, and have special scaling options on top of those available to

  // Accessible property names are escaped according to the following rules when accessed in the expression:
  // - '__' escapes to '__underscores__'
  // - '.' escapes to '__dot__'
  // - '-' escapes to '__dash__'
  // - '/' escapes to '__slash__'
  // - Property names that exactly match a CEL RESERVED keyword escape to '__{keyword}__'. The keywords are:

  // readOnlyRootFilesystem when set to true will force containers to run with a read only root file
  // system.  If the container specifically requests to run with a non-read only root file system
  // the PSP should deny the pod.
  // If set to false the container may run with a read only root file system if it wishes but it
  // will not be forced to.
  // +optional
  optional bool readOnlyRootFilesystem = 14;

  // limitation on request execution.  A value of `"Exempt"` means
  // that requests of this priority level are not subject to a limit
  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited

  // limitation on request execution.  A value of `"Exempt"` means
  // that requests of this priority level are not subject to a limit
  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited

  //   the IngressClass. Implementations can treat this as a separate PathType
  //   or treat it identically to Prefix or Exact path types.
  // Implementations are required to support all path types.
  // Defaults to ImplementationSpecific.
  optional string pathType = 3;

  // Backend defines the referenced service endpoint to which the traffic
  // will be forwarded to.

  // The number of old ReplicaSets to retain to allow rollback.
  // This is a pointer to distinguish between explicit zero and not specified.
  // Defaults to 10.
  // +optional
  optional int32 revisionHistoryLimit = 6;

  // Indicates that the deployment is paused.
  // +optional
  optional bool paused = 7;

  // The maximum time in seconds for a deployment to make progress before it

// CertificateSigningRequest objects provide a mechanism to obtain x509 certificates
// by submitting a certificate signing request, and having it asynchronously approved and issued.
//
// Kubelets use this API to obtain:
//  1. client certificates to authenticate to kube-apiserver (with the "kubernetes.io/kube-apiserver-client-kubelet" signerName).