// +optional
  optional Time time = 4;

  // FieldsType is the discriminator for the different fields format and version.
  // There is currently only one possible value: "FieldsV1"
  optional string fieldsType = 6;

  // FieldsV1 holds the first JSON version format as described in the "FieldsV1" type.
  // +optional
  optional FieldsV1 fieldsV1 = 7;