Add site.feed.updated = latest_post setting
#368
Conversation
|
Boolean config options are always restrictive. What if we went with something that allowed the user to decide from one of a list of values? Like |
lib/jekyll-feed/feed.xml
Outdated
| {% assign last_post = posts | first %} | ||
| {% assign last_updated = last_post.last_modified_at | default: last_post.date | default: site.time %} |
There was a problem hiding this comment.
latest_post.last_modified_at
This is a field from another plug-in, jekyll-last-modified-at, I think. (It requires that Git data is available, which isn't always true.) Looking at dependents, I'm not sure it's entirely worth it to support. Why did you add it here?
Also, if you're not going by published time, then you'd need to iterate through every post to get the latest modification date. Modifying an older post wouldn't reset this time.
There was a problem hiding this comment.
I don't mind supporting the jekyll-last-modified-at plugin, as it seems already supported by jekyll-feed. Good point on looping through, I'll amend the change to do that.
I think supporting it is relevant to the <updated> element. This value would otherwise be limited to original publishing dates only. I imagine people who care about this element to use my new option, would likely still want to increment it when they update existing posts, to ensure readers pick it up. Supporting this plugin, seems like a good option to offer for those people, so that at least there is a way to do that.
6000 dependents compared to 1 million for jekyll-feed is small indeed, but 6000 is a lot of sites. A loose search for both suggests there's at least 4000 sites with their source public on github.com using both. I imagine there's more usage among self-hosted sites, on other Git platforms, and in private repos.
There was a problem hiding this comment.
last_modified_at is already being used by jekyll-feed:
jekyll-feed/lib/jekyll-feed/feed.xml
Line 62 in 1ac64bc
It was added in 2015 with a dependency to jekyll-last-modified-at, but this dependency was removed in 2016. Now it relies on manually setting last_modified_at in frontmatter:
https://github.com/jekyll/jekyll-feed/search?q=last_modified_at&type=commits
last_modified_at is also supported by jekyll-seo-tag:
https://github.com/jekyll/jekyll-seo-tag/search?q=last_modified_at&type=code
IMHO jekyll-feed shouldn't stop using it and may use it for additional features.
Primary uses cases: 1. Reduce deployment churn in repositories that hold a docsite in addition to source code. These repositories currently regenerate and find "changed" files to deploy on every commit, even when nothing in the Jekyll site was changed. The only artefact changing each time is `feed.xml`. For example: https://github.com/qunitjs/qunit/commits/gh-pages 2. Improve reproducibility of the build, as highlighted via jekyll/jekyll#7187. By offering a choice that simply eliminates use of current time entirely, we do not even have to worry about mocking it.
Krinkle
changed the title
feed.updated_deterministic settingsite.feed.updated = latest_post setting
|
Cc @vincerubinetti and #387 |
Two main uses cases:
Reduce deployment churn in repositories that hold a docsite in
addition to source code. These currently regenerate and find
something new commit on every change, even when nothing in the
site has been changed. The only file changing each time is
feed.xml.
For example: https://github.com/qunitjs/qunit/commits/gh-pages
Improve reproducibility of the build, as highlighted via
Respect SOURCE_DATE_EPOCH environment variable (if set) over Time.now jekyll#7187,
by offering a choice that simply eliminates use of current time entirely,
not even having to mock it.