toJson method Null safety

Map<String, dynamic> toJson()

Implementation

Map<String, dynamic> toJson() {
  return {
    'title': title,
    'subtitle': subtitle,
    'authors': authors,
    'publisher': publisher,
    'publishedDate': publishedDate,
    'rawPublishedDate': rawPublishedDate,
    'averageRating': averageRating,
    'categories': categories,
    'contentVersion': contentVersion,
    'description': description,
    'language': language,
    'maturityRating': maturityRating,
    'pageCount': pageCount,
    'ratingsCount': ratingsCount,
    'imageLinks': imageLinks,
    'industryIdentifiers':
        industryIdentifiers.map((identifier) => identifier.toJson()).toList(),
    'previewLink': previewLink,
    'infoLink': infoLink,
    'canonicalVolumeLink': canonicalVolumeLink,
  };
}