This post refers to a legacy version of Siteleaf.
Now that you are sorting like a pro, we’ll move on to another new and exciting Liquid filter: where.
Where allows us to find content based on a parameter. If you are coming from Jekyll, you’ll be happy to know it follows the same syntax.
For example, here’s how we could find all pages titled “Foo”:
{% assign foo_pages = site.pages | where:"title","Foo" %}
As with sort, you can use any property like date, title, slug, even metadata and taxonomy. Below are few real-world examples you might find useful.
Show posts by author
So I just created a fancy new bio page for myself, and now I want to display posts I’ve written alongside my bio.
To locate posts written by a specific author across the entire site, we can start with site.posts. Then we can apply the where filter with author as a parameter:
{% assign my_posts = site.posts | where:"author","Skylar Challand" %}
You can also use nested properties such as author.email:
{% assign my_posts = site.posts | where:"author.email","skylar@siteleaf.com" %}
Now we can display our matching posts using the my_posts variable we just created:
<ul>
{% for post in my_posts %}
<li><a href="{{post.url}}">{{post.title}}</a></li>
{% endfor %}
</ul>
Don’t repeat yourself: Since the title on my bio page matches the author name (“Skylar Challand”), we could use title as a variable and make our theme code reusable:
{% assign my_posts = site.posts | where:"author",title %}
Show featured posts
In the previous tutorial we showed you how to use metadata to create “sticky” posts.
Using the same metadata, we could grab all posts with this flag:
{% assign sticky_posts = site.posts | where:"meta.sticky","yes" %}
The same could be applied to any metadata. For example, we could find all posts with a color of “Red”:
{% assign red_posts = site.pages | where:"meta.color","Red" %}
Or posts with a particular tag:
{% assign tagged_posts = site.posts | where:"taxonomy.tags","whiskey" %}
Mm whiskey.
Filter by year
You can also filter content by date parts including year, month, and day.
Here’s how we could get all posts published this year:
{% assign latest_posts = site.posts | where:"year","2015" %}
Again we could take this a step further and use a variable in place of year:
{% assign this_year = site.date | date:"%Y" %}
{% assign new_posts = site.posts | where:"year",this_year %}
Follow @siteleaf and stay tuned for more Advanced Liquid!