Add RSS feed icon to tags

[tzinm]

Currently, tabi theme generates RSS feeds for individual tags (e.g., this feed), but these feeds aren't easily discoverable by visitors. The only visible RSS related icon is located in the footer.

Possible approach

Tag pages

When selecting a tag, all associated entries are listed under a title displaying the tag name. The suggestion is to add an RSS feed icon next to the tag name, making it clearer that a dedicated feed is available, similar to how it is implemented in the PaperMod theme for Zola. The placement (left or right of the title) could be a design choice or configurable as a preference.

Tag index page

If a site enables tag listings, the RSS icon could also be displayed next to each tag in the index, alongside the number of associated entries. Once the RSS feed subscription is made easily accessible on individual tag pages, this would be an additional option. It would further enhance usability by allowing readers to subscribe to the feed of their preferred tag directly from the tag index page.

[welpo]

I like this idea!

It shouldn't be too hard to implement. Would you like to try to contribute to tabi with this feature? I'd be happy to provide any guidance necessary.

Let me know! :)

[tzinm]

I'd love to contribute to tabi! I’ve been going through the documentation for both Zola and Tera to better understand how the templates are structured, but I’ll likely need some guidance along the way 🙂

I’ve broken the implementation down into two parts (perhaps it might be better to create 2 PR?):

Tag Index Page

This seems straightforward. I think modifying the list.html template inside the tags directory should be enough to include the RSS feed icon.

Tag Pages

For individual tag pages, I noticed that the page header is generated using the page_header.html macro. I see two possible approaches to implementing the RSS feed icon here:

1. Modify single.html template (quickest approach). Directly replace the call to page_header.html macro with its content inside the template, adding the necessary markup for the RSS feed icon. The downside is that if we later update the page headers for consistency across different sections, we would also need to remember to modify this template separately.
2. Modify page_header.html macro (more flexible approach). Add a condition inside the macro that checks whether an optional parameter is set to display the RSS feed icon. This makes the solution more reusable, especially if a similar feature is later added for category pages.

Would love to hear your thoughts on which approach makes more sense for tabi!

[welpo]

Feel free to create the PR for tag index page, then we can discuss tag pages (I'm not yet sure what the ideal solution is here)

I'm leaning towards making feed_icon show both the icon on the footer + on tag pages. Not sure if a user may prefer to only show one… Thoughts?

[tzinm]

Alright, I hope to move forward with the feed icon in tag index page in the next few days.

If I'm not wrong... once we activate the RSS feed on our site, it is also activated for the tags (even if they aren't easily discoverable). So, I'd choose to use feed_icon to display the icon both in the footer and for the tags.

[tzinm]

While working on the implementation of the feed icons in the tag index page, I encountered the following scenario:

Some tags may be assigned to pages that don't have a date field in their frontmatter. In certain cases, this can result in the absence of an RRS feed, even if feed = true is set in tags taxonomies in config.toml. This appears to be due To Zola's behaviour, which likely enforces the RSS specification by only generating feeds for tags that contain one entry with a valid date field.

A consequence of this behaviour is that clicking the feed icon for such tags results in a 404 page, since the corresponding atom.xml file doesn't exist. For example, if we try to load the feed for the tag bash, which is associated only with project pages that lack a date field in their frontmatter, tabi will display 404 page.

The ideal approach might be to handle this scenario similarly to the hide_from_feed or hide_from_main_feed. When some of those settings are enabled, prevent specific pages from being included in the feed without blocking the atom.xml file from being generated.

tabi/templates/atom.xml

Lines 72 to 80 in f25dfe3

	{%- if macros_settings::evaluate_setting_priority(setting="hide_from_feed", page=page, default_global_value=false) == "true" -%}
	{%- continue -%}
	{%- endif -%}
	{#- Skip if hide_from_main_feed is true and this is the main feed -#}
	{%- if macros_settings::evaluate_setting_priority(setting="hide_from_main_feed", page=page, default_global_value=false) == "true"
	and not section
	and not term -%}
	{%- continue -%}
	{%- endif -%}

To handle this scenario, I see two possible approaches:

1. Check whether at least one page associated with the tag has a date field, ensuring that the atom.xml file has been generated. However, I’m unsure if this check can be performed directly in templates/tags/list.html.
2. Maintain the current behaviour where the atom.xml file is not generated if no eligible pages exist, but modify the 404.html page to display a more informative message when a tag’s feed is unavailable. Similarl to how missing translations are handled.

What do you think about these approaches? Any other ideas?

P.S. This same scenario also applies to individual tag pages.