How do I create a quarto filter which can update the description of a post listing?

[mckabue]

Description

From my tests (and from code), it appears that the message of a listing post cannot be updated on runtime (when quarto is rendering the HTML).

A want a lua filter that overrides this functionality and instead generates a custom description will be used by the listing page.

[mcanouil]

Could you share what you tried concretely for your filter?

[mckabue]

posts/welcome/index.qmd

---
title: "Welcome To My Blog"
author: "Tristan O'Malley"
date: "2024-05-01"
categories: [news]
filters:
  - at: pre-ast
    path: description-update.lua
---

This is the first post in a Quarto blog. Welcome!

![](thumbnail.jpg)

Since this post doesn't specify an explicit `image`, the first image in the post will be used in the listing page of posts.

posts/welcome/description-update.lua

return {
  ---@param doc pandoc.Pandoc
  ---@return pandoc.Pandoc
  Pandoc = function (doc)
    local meta = doc.meta
    meta['description'] = pandoc.Str('This is an updated description')
    
    return pandoc.Pandoc(doc.blocks, meta)
  end
}

Display In the post page:

Display In the default Listings Page:

[cscheid]

I don't think that's possible today, unfortunately. I've opened an issue to track: #9811