old_contents: DEFAULT_FIELDS = [
      'locales.title',
      'locales.summary',
      'locales.description',
      'locales.lang',
      'author',
      'editor',
      'activities',
      'url',
      'isbn',
      'book_types',
      'publication_date',
      'langs',
      'nb_pages'
  ]
  
  DEFAULT_REQUIRED = [
      'locales',
      'locales.title',
      'book_types'
  ]
  
  LISTING_FIELDS = [
      'locales',
      'locales.title',
      'activities',
      'author',
      'quality',
      'book_types'
  ]
  
  fields_book = {
      'fields': DEFAULT_FIELDS,
      'required': DEFAULT_REQUIRED,
      'listing': LISTING_FIELDS
  }
  
new_contents: DEFAULT_FIELDS = [
      'locales.title',
      'locales.summary',
      'locales.description',
      'locales.lang',
      'author',
      'editor',
      'activities',
      'url',
      'isbn',
      'book_types',
      'publication_date',
      'langs',
      'nb_pages'
  ]
  
  DEFAULT_REQUIRED = [
      'locales',
      'locales.title',
      'book_types'
  ]
  
  LISTING_FIELDS = [
      'locales',
      'locales.title',
      'locales.summary',
      'activities',
      'author',
      'quality',
      'book_types'
  ]
  
  fields_book = {
      'fields': DEFAULT_FIELDS,
      'required': DEFAULT_REQUIRED,
      'listing': LISTING_FIELDS
  }
  
subject: Add summary to book listing