toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (expirationMs != null) 'expirationMs': expirationMs!,
if (field != null) 'field': field!,
if (requirePartitionFilter != null)
'requirePartitionFilter': requirePartitionFilter!,
if (type != null) 'type': type!,
};