Upgrading from 2.x to 3.x
Upgrading from an older version of Jekyll? A few things have changed in 3.0 that you’ll want to know about.
Before we dive in, go ahead and fetch the latest version of Jekyll:
$ gem update jekyll
Please note: Jekyll 3.2 requires Ruby version >= 2.1
Diving in
Want to get a new Jekyll site up and running quickly? Simply
run jekyll new SITENAME
to create a new folder with a bare bones
Jekyll site.
site.collections has changed
In 2.x, your iterations over site.collections
yielded an array with the collection
label and the collection object as the first and second items, respectively. In 3.x,
this complication has been removed and iterations now yield simply the collection object.
A simple conversion must be made in your templates:
-
collection[0]
becomescollection.label
-
collection[1]
becomescollection
When iterating over site.collections
, ensure the above conversions are made.
For site.collections.myCollection
in Jekyll 2, you now do:
{% assign myCollection = site.collections | where: "label", "myCollection" | first %}
This is a bit cumbersome at first, but is easier than a big for
loop.
Dropped dependencies
We dropped a number of dependencies the Core Team felt were optional. As such, in 3.0, they must be explicitly installed and included if you use any of the features. They are:
- jekyll-paginate – Jekyll’s pagination solution from days past
- jekyll-coffeescript – processing of CoffeeScript
- jekyll-gist – the
gist
Liquid tag - pygments.rb – the Pygments highlighter
- redcarpet – the Markdown processor
- toml – an alternative to YAML for configuration files
- classifier-reborn – for
site.related_posts
Future posts
A seeming feature regression in 2.x, the --future
flag was automatically enabled.
The future flag allows post authors to give the post a date in the future and to have
it excluded from the build until the system time is equal or after the post time.
In Jekyll 3, this has been corrected. Now, --future
is disabled by default.
This means you will need to include --future
if you want your future-dated posts to
generate when running jekyll build
or jekyll serve
.
Future Posts on GitHub Pages
An exception to the above rule are GitHub Pages sites, where the --future
flag remains enabled
by default to maintain historical consistency for those sites.
Layout metadata
Introducing: layout
. In Jekyll 2 and below, any metadata in the layout was merged onto
the page
variable in Liquid. This caused a lot of confusion in the way the data was
merged and some unexpected behaviour. In Jekyll 3, all layout data is accessible via layout
in Liquid. For example, if your layout has class: my-layout
in its YAML front matter,
then the layout can access that via {{ layout.class }}
.
Syntax highlighter changed
For the first time, the default syntax highlighter has changed for the
highlight
tag and for backtick code blocks. Instead of Pygments.rb,
it’s now Rouge. If you were using the highlight
tag with certain
options, such as hl_lines
, they may not be available when using Rouge. To
go back to using Pygments, set highlighter: pygments
in your
_config.yml
file and run gem install pygments.rb
or add
gem 'pygments.rb'
to your project’s Gemfile
.
Relative Permalink support removed
In Jekyll 3 and above, relative permalinks have been deprecated. If you created your site using Jekyll 2 and below, you may receive the following error when trying to serve or build:
Since v3.0, permalinks for pages in subfolders must be relative to the site
source directory, not the parent directory. Check
https://jekyllrb.com/docs/upgrading/ for more info.
This can be fixed by removing the following line from your _config.yml
file:
relative_permalinks: true
Permalinks no longer automatically add a trailing slash
In Jekyll 2, any URL constructed from the permalink:
field had a trailing slash (/
) added to it automatically. Jekyll 3 no longer adds a trailing slash automatically to permalink:
URLs. This can potentially result in old links to pages returning a 404 error. For example, suppose a page previously contained the YAML permalink: /:year-:month-:day-:title
that resulted in the URL example.com/2016-02-01-test/
(notice the trailing slash), Jekyll internally generates a folder named 2016-02-01-test
. In Jekyll 3, the same permalink:
generate the file 2016-02-01-test.html
and the URL for the same page will be example.com/2016-02-01-test
, and consequently any links to the old URL will result in a 404 error. In order to maintain the same URLs and avoid this problem, a trailing slash should be added to the permalink:
field, for example permalink: /:year-:month-:day-:title/
.
All my posts are gone! Where’d they go!
Try adding future: true
to your _config.yml
file. Are they showing up now? If they are, then you were ensnared by an issue with the way Ruby parses times. Each of your posts is being read in a different timezone than you might expect and, when compared to the computer’s current time, is “in the future.” The fix for this is to add a timezone offset to each post (and make sure you remove future: true
from your _config.yml
file). If you’re writing from California, for example, you would change this:
---
date: 2016-02-06 19:32:10
---
to this (note the offset):
---
date: 2016-02-06 19:32:10 -0800
---
My categories have stopped working!
If you organized your categories as /_posts/code/2008-12-24-closures.md
, you will need to restructure your directories to put the categories above the _posts
directories, as follows: /code/_posts/2008-12-24-closures.md
.
Did we miss something? Please click “Improve this page” above and add a section. Thanks!