darling

README

💔 Darling: A Filtering RSS Aggregator

Darling is an RSS aggregator—it can combine multiple RSS or Atom feeds into a single feed—that provides simple filtering. It thus can serve as a feed muxer and demuxer.

Aggregation

Darling will transform an unlimited number of feeds into a single feed. For instance, to produce a unified feed of posts from Lobste.rs and Tilde News: darling https://tilde.news/rss https://lobste.rs/rss. All items are interleaved into a single feed, sorted by creation time.

Word Matching

Darling supports blacklisting (based on case-insensitive, whole-word matching) and whitelisting. Whitelisting takes priority over blacklisting. The asterisk is a wildcard matcher, and multiple tokens to match may be provided.

To produce a list of Julia Evans blog posts that aren't about SQL or her zine: darling -b sql -b zine -b zines https://jvns.ca/atom.xml.

To demux her feed into one that's zine-specific: darling -b "*" -w zine -w zines https://jvns.ca/atom.xml.

Be aware that producing an empty feed is a valid result!

Time Matching

Darling also supports time-based matching, returning all items published (not updated) after a given time. This time can be relative to now or a specific date or datetime. For relative times, a subset of the standard Unix date format tokens are used: YmdHMS.

• Every NetNewsWire commit found from the last twelve hours: darling --since 12H https://github.com/brentsimmons/NetNewsWire/commits/master.atom
• Every Dinosaur Comics entry found from the last week: darling --since 7d https://qwantz.com/rssfeed.php
• Every Lambda the Ultimate entry found since the beginning of 2019: darling http://lambda-the-ultimate.org/rss.xml --since 2019-01-01
• Every Hill Cantons entry found since Halloween, 2018: darling https://hillcantons.blogspot.com/feeds/posts/default?alt=rss --since 2018-10-31T00:00:00-04:00

Note that darling does not currently (and may never) handle paging through older issues on feeds which support offsets; adjust your expectations accordingly when trying to load older content.

Limits

You can also restrict the number of items process per feed. If you wanted to get only the most recent item from film critic Nathan Rabin, perhaps to support a widget: https://www.nathanrabin.com/happy-place/?format=rss -n 1.

Word matching, time matching, and limits may all be applied within a single call: darling -n 1 --since 3d --b cat --b dog --b ghost https://strangeco.blogspot.com/feeds/posts/default would return a feed consisting of the last post from the Strange Company blog, but only if it was in the last three days and didn't mention a dog, a cat, or a ghost (and especially not a ghost dog or cat).