// are specific to the node & CRI configuration.  It is assumed that all
  // handlers are available on every node, and handlers of the same name are
  // equivalent on every node.
  // For example, a handler called "runc" might specify that the runc OCI
  // runtime (using native Linux containers) will be used to run the containers
  // in a pod.
  // The Handler must be lowercase, conform to the DNS Label (RFC 1123) requirements,
  // and is immutable.

  // values are specific to the node & CRI configuration.  It is assumed that
  // all handlers are available on every node, and handlers of the same name are
  // equivalent on every node.
  // For example, a handler called "runc" might specify that the runc OCI
  // runtime (using native Linux containers) will be used to run the containers
  // in a pod.
  // The runtimeHandler must be lowercase, conform to the DNS Label (RFC 1123)

  // items is the list of VolumeAttachments
  repeated VolumeAttachment items = 2;
}

// VolumeAttachmentSource represents a volume that should be attached.
// Right now only PersistenVolumes can be attached via external attacher,
// in future we may allow also inline volumes in pods.
// Exactly one member can be set.
message VolumeAttachmentSource {

  // (`scheme://host:port/path`). Exactly one of `url` or `service`
  // must be specified.
  //
  // The `host` should not refer to a service running in the cluster; use
  // the `service` field instead. The host might be resolved via external
  // DNS in some apiservers (e.g., `kube-apiserver` cannot resolve
  // in-cluster DNS as that would be a layering violation). `host` may
  // also be an IP address.
  //

  // are referenced by the Pod and that use "WaitForFirstConsumer"
  // allocation is to be attempted.
  // +optional
  optional string selectedNode = 1;

  // PotentialNodes lists nodes where the Pod might be able to run.
  //
  // The size of this field is limited to 128. This is large enough for
  // many clusters. Larger clusters may need more attempts to find a node

  // e.g. `meta.k8s.io/v1.DeleteOptions` or `meta.k8s.io/v1.CreateOptions`. This may be
  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;

  // are specific to the node & CRI configuration.  It is assumed that all
  // handlers are available on every node, and handlers of the same name are
  // equivalent on every node.
  // For example, a handler called "runc" might specify that the runc OCI
  // runtime (using native Linux containers) will be used to run the containers
  // in a pod.
  // The handler must be lowercase, conform to the DNS Label (RFC 1123) requirements,
  // and is immutable.

  // e.g. `meta.k8s.io/v1.DeleteOptions` or `meta.k8s.io/v1.CreateOptions`. This may be
  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;

  //
  // - In: the requirement is satisfied if at least one container exit code
  //   (might be multiple if there are multiple containers not restricted
  //   by the 'containerName' field) is in the set of specified values.
  // - NotIn: the requirement is satisfied if at least one container exit code
  //   (might be multiple if there are multiple containers not restricted

  // The CSI driver is responsible for parsing and validating the information passed in as VolumeContext.
  //
  // The following VolumeConext will be passed if podInfoOnMount is set to true.
  // This list might grow, but the prefix will be used.
  // "csi.storage.k8s.io/pod.name": pod.Name
  // "csi.storage.k8s.io/pod.namespace": pod.Namespace
  // "csi.storage.k8s.io/pod.uid": string(pod.UID)