ThorneLabs

A Better Way to Display Random Jekyll Posts on Page Load or Refresh Using jQuery and JSON

• Updated March 17, 2019

In a previous post I described how to display random Jekyll posts during each page load or refresh using Javascript. This post will produce the same result but will achieve it with jQuery and JSON.

The JSON File

Because Jekyll is a static-site generator, you do not have a database to query. For this whole thing to work, you need some sort of file to search through. This is where JSON comes in.

Jekyll will generate a JSON file that will contain every post with its associative metadata.

Create file search.json in your root Jekyll directory with the following contents:

---
---
[
    {% for post in site.posts %}
    {
      "title"    : "{{ post.title }}",
      "href"     : "{{ post.url }}",
      "date"     : {
         "day"   : "{{ post.date | date: "%d" }}",
         "month" : "{{ post.date | date: "%B" }}",
         "year"  : "{{ post.date | date: "%Y" }}"
      }
    }
    {% unless forloop.last %},{% endunless %}
    {% endfor %}
]

Each time you run jekyll build, a search.json file will be generated in the Jekyll _site folder containing all your posts and their associative metadata that you can search through using jQuery.

The jQuery Code

First, make sure you have already loaded the jQuery library within the head tags of your website (the missing http: in the URL is not a typo):

<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>

Second, put the following jQuery code within the head tags of your website (modify the numberOfPosts variable depending on how many posts you want displayed):

<script type="text/javascript">

    function generateRandomPosts()
    {
        $.getJSON("/search.json", function(data) {
            console.log("[search.json loaded for random posts]");

            var postsCount = data.length;
            var posts = data;

            var randomIndexUsed = [];
            var counter = 0;
            var numberOfPosts = 5;

            var divRandomPosts = $("#random_posts");

            divRandomPosts.append('<h2>other posts</h2><hr />');

            while (counter < numberOfPosts)
            {
                var randomIndex = Math.floor(Math.random() * postsCount);

                if (randomIndexUsed.indexOf(randomIndex) == "-1")
                {
                    var postHREF = posts[randomIndex].href;
                    var postTitle = posts[randomIndex].title;

                    if (counter == (numberOfPosts - 1))
                    {
                        divRandomPosts.append('<p><a href="' + postHREF + '">' + postTitle + '</a></p>');
                    }
                    else
                    {
                        divRandomPosts.append('<p><a href="' + postHREF + '">' + postTitle + '</a></p><hr />');
                    }

                    randomIndexUsed.push(randomIndex);

                    counter++;
                }
            }
        });
    }

    $(document).ready(function() {
        generateRandomPosts();
    });

</script>

On each page load or refresh the generateRandomPosts function will run and append HTML to the random_posts div.

The HTML Markup

Put the following HTML markup within the body tags where you want the randomized list of posts to appear on your website:

<div id="random_posts">
</div>

Once the above Liquid, jQuery, and HTML is in place, run jekyll build, and re-upload the generated website to your webserver. With each page load or refresh, a random list of posts will be displayed.

References