Deduplicating posts after URL changes in Artemis

Occasionally, sites that publish web feeds change the URL of a post that has just been published. This can be for several reasons. For example, I sometimes change post permalinks immediately after publishing because I notice a typo, or because the CMS I use calculated a default permalink that I don’t want to use and I forgot to change it.Until now, Artemis, the calm web reader I maintain, has done nothing if a post has changed its permalink. Importantly, Artemis considers the post URL as a unique identifier. This means that if a post changes its URL, a new record for the post will be added to the database. Today, however, I have added logic to deduplicate posts where the title is the same but the URL has changed.The way it works is as follows. When a user’s feed is computed, Artemis checks how many posts published by the same author have the same title per day. If two or more posts have the same title in a day, Artemis will show the most recent version of the post. All other instances…