           author_id: ObjectId(article.author_id) if article.author_id
           fair_id: ObjectId(article.fair_id) if article.fair_id
           vertical_id: ObjectId(article.vertical_id) if article.vertical_id
+          section_ids: article.section_ids.map(ObjectId) if article.section_ids
           auction_id: ObjectId(article.auction_id) if article.auction_id
           partner_ids: article.partner_ids.map(ObjectId) if article.partner_ids
           show_ids: article.show_ids.map(ObjectId) if article.show_ids

  limit: @number().max(Number API_MAX).default(Number API_PAGE_SIZE)
  offset: @number()
  vertical_id: @objectId()
  artist_id: @objectId()
  artwork_id: @objectId()
  fair_ids: @array()

  fair_id: @objectId().allow(null)
  auction_id: @objectId().allow(null)
  vertical_id: @objectId().allow(null)
  section_ids: @array().items(@objectId()).default([])
  biography_for_artist_id: @objectId().allow(null)
  featured: @boolean().default(false)
  exclude_google_news: @boolean().default(false)
