How to iterate and retrieve from YAML _data in Jekyll? - arrays

Question

I'm trying to build a Jekyll blog. But I never used YAML before and I'm going mad with the logic of this thing.
First I wrote a YAML file in _data/authors.yml with a list of authors and their respective meta-info:
- authors:
- user: andre
name: Andre Santos
site: http://test.dev
email: andre#test.dev
- user: john
name: John Doe
site:
email: john.doe#test.dev
Now I want to do two very simple things: first, to iterate over all authors, displaying some info about them:
{% for list in site.data.authors %}
{% for author in list %}
{{ author.user }} - {{ author.user.name }}
{% endfor %}
{% endfor %}
But it shows nothing!
Now in some other part of the code I just want to retrieve info from a specific user:
{% assign the_user = site.data.authors.authors[post.username] %}
{{ the_user.name }}
And, once again it shows nothing! I have no idea what I'm doing wrong, I tried lots of other solutions, iterations, but I can't make heads or tails about how to iterate YAML files, and I don't know Ruby so most of the solutions I found in this site don't work for me when I adapt them into Jekyll + Liquid.
What am I doing wrong? How to access those variables?

Answer 1

Problem solved!
After some long deliberation, I got a very simple solution, based on 2 steps: change from YAML to JSON, and then understanding Jekyll returns a Ruby Hash instead of an array.
So, the final file, authors.json:
{
"andre": {
"name": "Andre Santos",
"site": "http://test.dev",
"email": "andre#test.dev"
},
"john": {
"name": "John Doe",
"site": "",
"email": "john.doe#test.dev"
}
}
Now that the file is corrected, let's take care of selecting one of its items and showing it.
{{ site.data.authors[post.author].name }}
If post.author = "andre", the template will return Andre Santos. First problem, solved!
Now, Jekyll is quite dumb and still doesn't works fine with JSON. No matter what we do, it will iterate poorly with it. So, let's analyse the following situation:
In a test, I decided to dump the iteration. So:
{% for author in site.data.author %}
{{ author }}
----
{% endfor %}
It produces the following result:
andre{"name"=>"Andre Santos", "site"=>"test.dev";, "email"=>"andre#test.dev"} ----
john{"name"=>"John Doe", "site"=>nil, "email"=>"john.doe#test.dev"} ----
This result shows Jekyll isn't producing an array, but a Hash (notice the => symbol). So, let's try to deal with it as a Hash. If I try to print {{ author[0] it will show andre and john. Excellent! So, the next part of the Hash (the metadata) is, in fact author[1].
The final code to display the info:
{% for author in site.data.authors %}
Username: {{ author[0] }}
Full Name: {{ author[1]["name"] }}
{% if author[1]["site"] != "" %}
Site: {{ author[1]["site"] }}
{% endif %}
E-Mail: {{ author[1]["email"] }}
-----
{% endfor %}
And the result:
Username: andre
Full Name: Andre Santos
Site: http://test.dev
E-Mail: andre#test.dev
----
Username: john
Full Name: John Doe
E-Mail: john.doe#test.dev
----
Ta da!
So, to wrap it up: drop YAML and use JSON, get info from a specific part of the JSON using simple dot notation and key. When using for, deal with it as a Hash. The code becomes a little harder to deal with, but at least it's working as I wanted. In the future, if Jekyll takes JSON a little more seriously, it will probably let us iterate it a little easier.
Thank you all!

Answer 2

You can simplify your data file :
- user: andre
name: Andre Santos
site: http://test.dev
email: andre#test.dev
- user: john
name: John Doe
site:
email: john.doe#test.dev
Now you can get your datas like this :
<ul>
{% for author in site.data.authors %}
<li>{{ author.user }} - {{ author.name }}</li>
{% endfor %}
</ul>
Or like this :
{% assign the_user = site.data.authors | where: "user", post.username | first %}
{{ the_user.name }}