func (si SearchIndex) UpdateFeed(feed content.Feed) {
si.logger.Infof("Updating article search index for feed '%s'\n", feed)
newArticleLinks := map[string]bool{}
for _, a := range feed.NewArticles() {
newArticleLinks[a.Data().Link] = true
}
var articles []content.Article
for _, a := range feed.ParsedArticles() {
if newArticleLinks[a.Data().Link] {
articles = append(articles, a)
}
}
si.batchIndex(articles)
}