How to loop through all files in Jekyll's _data folder? - jekyll

Question

How can I loop through every file in my _data folder in Jekyll?
Currently I have a list of files in a file called sidebarlist.yml like this:
- file1
- file2
- file3
In order to loop through all of these files, I use this code:
{% for sidebar in site.data.sidebarlist %}
{% for entry in site.data.sidebars[sidebar].entries %}
...
{% endfor %}
{% endfor %}
I would like to avoid using sidebarlist.yml and just iterate through all files within _data automatically. Can I do this?

Answer 1

Nesting loops allows you to loop through the contents of _data files.
When I did this I used a subdirectory, since I didn't want to loop through every data file, and I think that applies to many use cases. It also keeps my _data directory a little tidier.
My _data directory looks like this:
_data/
navigation.yml
news.yml
people/
advisors.yml
board.yml
staff.yml
Each of the files within people/ uses a structure like this:
- name: Anne Smith
role: Role A
url: mysite.com
- name: Joe Shmoe
role: Role B
url: mysite.org
And on the page where I'm looping through each of these data files:
{% for people_hash in site.data.people %}
{% assign people = people_hash[1] %}
{% for person in people %}
<li>{{ person.name }}, {{ person.role }}</li>
{% endfor %}
{% endfor %}
This results in:
<li>Anne Smith, Role A</li>
<li>Joe Shmoe, Role B</li>
It's very similar to what you've already done, but eliminates the need for that extra yaml file.
Note the use of people_hash[1] - this is what is targeting the appropriate values within the array.
If instead you do:
{% for people_hash in site.data.people %}
{% assign people = people_hash[1] %}
<pre>{{ people }}</pre>
{% endfor %}
You'll get the array of values that is returned, which should help you debug your template.

Answer 2

I have read your question title, and I will answer your last question:
You can't loop through files you keep in _data folder. According to Jekyll Variable doc and Jekyll Directory structure all the file in _data with supported extension .yml .yaml .csv .jsonby default will be loaded in site.data like #wasthishelpfull's answered and you access it via {{site.data.*filename.data*}} and loop though like this answer
If you wanna loop through files, create a folder (no underscore) serve it as static files, and use jquery.get() for the data in the file.
Or change _data to data in _config.yml by adding data_source: data and access at a url endpoint /data see this post for more

Answer 3

According to the documentation, jekyll will load YAML resources (.yml, .yaml, .json, and .csv files) directly into site.data. If your files use one of these formats, you can do:
{% for data in site.data %}
...
{% endfor %}

Answer 4

I assume you need to access jekyll site.data in a way of looping multi levels object:
{% assign my_data = site.data %}
{% assign my_level = "sidebarlist.sidebars.sidebar" | split: "." %}
{% for level in my_level %}
{% assign my_data = my_data[level[i]] %}
{% for data in my_data %}
{{ data }} : {{ my_data[data] }}
{% endfor %}
{% endfor %}