Feed format mismatch

A feed’s file name says one format, but the feed is built as another, such as rss.xml built as an Atom feed. A file name says a format if it is rss.xml or atom.xml, or ends in .rss, .atom or .json.

What you’ll see

warning  Feed format mismatch: `templates/feed.xml` makes `rss.xml` an Atom feed
  Add `templates/rss.xml` to build it as an RSS feed.
  More: https://statac.dev/e/feed-format-mismatch/

In the terminal, the message also shows the file and line, if there is one, and marks the exact text.

Why Statac warns

Statac has no feed template of its own. Each feed is built with the template named as its file, such as templates/rss.xml for rss.xml. If there isn’t one, Statac uses the template named feed with the feed’s extension, such as templates/feed.json for feed.json, and otherwise templates/feed.xml. A list with feed: [atom.xml, rss.xml] and only templates/feed.xml therefore publishes the same Atom feed twice, once under the RSS feed’s name, and nothing else would tell you.

Statac tells the format from the feed it built: an <rss> root is RSS, a <feed> root is Atom, and a JSON Feed names its version. A name such as feed.xml or index.xml says no format, so Statac never warns about a feed with that name.

How to fix it

Add the template the message names, written in the format the feed’s name says. The docs have an Atom template and an RSS template to copy: see the template.

If the feed’s own template is the one building it, write that template in the format its name says, or rename the feed in the feed: line.

If you meant both names to carry the same feed, quieten the warning with quiet: [feed-format-mismatch] in statac.yaml.

Example

In content/index.md:

---
title: Home
feed: [atom.xml, rss.xml]
---

With only templates/feed.xml, an Atom template, both feeds are Atom. With an RSS template beside it, rss.xml is RSS:

templates/
  feed.xml
  rss.xml

Its name

Name	feed-format-mismatch
In the terminal	statac explain feed-format-mismatch
To stop showing it	quiet: [feed-format-mismatch] in statac.yaml, once you have understood it. Statac still counts it.