Jekyll: Generator to link to all subpages in a static hierarchy - jekyll

Question

I'm trying to write a static site with Jekyll that has a few layers to it. What's the best way to generate links to all subpages within a section?
For example, if I have a site structure like this:
landing
- Topic A
- Content 1
- Content 2
- Content 3
- Topic B
- Content 1
- Content 2
- Content 3
What would be the best way to create links to each of the Content pages from its Topic page? And, is there a simple way to link to all the Topic pages from the landing?
These are not posts, just static pages. It would be really great if I could just do {% for topic.each %} ...etc. and print the links out.

Answer 1

I would not use posts for this purpose (as yaitloutou suggests). I would read the hierarchy from the directory structure (solution 1) or create two seperate collections (solution 2). You can let the collections from solution 2 share the same layout if you want that.
1. Using pages
Create a directory structure with index.md pages and loop over the Jekyll veriable called 'site.pages' to create the menu.
index.md
topic-a/index.md
content-1/index.md
content-2/index.md
content-3/index.md
topic-b/index.md
content-1/index.md
content-2/index.md
content-3/index.md
And loop over all pages like this:
<ul>
{% assign sitepages = site.pages | sort: 'order' %}
{% for sitepage in sitepages %}
<li {% if page.url == sitepage.url %} class="active"{% endif %}>
{{ sitepage.title }}
</li>
{% endfor %}
</ul>
If you want the nested structure, you can do something like this. Or if you want only the results for Topic A, you can do this:
<ul>
{% assign sitepages = site.pages | sort: 'order' %}
{% for sitepage in sitepages %}
{% if sitepage.url contains 'topic-a' %}
<li {% if page.url == sitepage.url %} class="active"{% endif %}>
{{ sitepage.title }}
</li>
{% endif %}
{% endfor %}
</ul>
2. Using collections (simplest solution and quickest build)
Create a collection Topic A and create another collection Topic B. Your config file should look like this:
collections:
topic-a:
output: true
permalink: /topic-a/:path/
topic-b:
output: true
permalink: /topic-b/:path/
Outputting the items of one topic goes like this:
{% assign atopics = site.topic-a | sort: 'order' %}
{% for atopic in atopics %}
<li {% if page.url == atopic.url %} class="active"{% endif %}>
{{ atopic.title }}
</li>
{% endfor %}
</ul>
You should create a _topic-a and a _topic-b directory with your content-1.md, content-2.md, etc. files.
Note that both solutions have YML variables called 'order', to determine the order of appearance of the items/pages. This looks like this:
---
title: mytitle
layout: mylayout
order: 50
---
mycontent

Answer 2

I'll propose here 2 ways, you can determine the "best" according to your specific needs/situation, and which one sound more adapted to them.
first of all, "posts" and "pages" are basically just collections of md/html files. with some variables associated to each one.
to generate files with this structure, you can:
1. Using _posts and page.categories
put all the sub-files in _posts (the 2017-01-01- is just a place holder)
_posts/
- 2017-01-01-content-a-1.md
- 2017-01-01-content-a-2.md
- 2017-01-01-content-a-3.md
- 2017-01-01-content-b-1.md
- 2017-01-01-content-b-2.md
- 2017-01-01-content-b-3.md
add appropriate categories to each file:
2.1. for posts caontent-a-* add category: topic-a (in this order) by adding this line in the yaml front matter at top of each of them:
---
layout: page # or any appropriate layout
category: topic-a
---
2.2. for posts caontent-b-* add category: topic-b
set a premalink to ignore the date, and create the desired structure, by adding the following line to _config.yml:
defaults:
-
scope:
path: "_posts" # to all the file in posts
values:
permalink: /landing/:categories/:title.html # set this as default permalink value
you still can specify a permalinks per post in its front matter, or just add the permalink line to each md folder front matter.
the above will generate the desired structure.
loop through all the
{% for entry in site.posts %}
{% if entry.category == type-a %}
<!-- do A stuff -->
{% elsif entry.category == type-b %}
<!-- do B stuff -->
{% endif %}
{% endfor %}
2. Using collections:
it's similar to the above, but instead of using the already existent _postscollection you'll start by creating a new collection (one advantage is that you'll not need to add a date )
any of the approaches above will generate this structure inside _site
landing/
type-a/
content-a-1/
index.html
content-a-2/
index.html
...
type-b/
...