Writing posts

One of Jekyll’s best aspects is that it is “blog aware”. What does this mean, exactly? Well, simply put, it means that blogging is baked into Jekyll’s functionality. If you write articles and publish them online, this means that you can publish and maintain a blog simply by managing a folder of text-files on your computer. Compared to the hassle of configuring and maintaining databases and web-based CMS systems, this will be a welcome change!

The Posts Folder

As explained on the directory structure page, the _posts folder is where your blog posts will live. These files are generally Markdown or HTML, but can be other formats with the proper converter installed. All posts must have YAML Front Matter, and they will be converted from their source format into an HTML page that is part of your static site.

Creating Post Files

To create a new post, all you need to do is create a new file in the _posts directory. How you name files in this folder is important. Jekyll requires blog post files to be named according to the following format:

YEAR-MONTH-DAY-title.MARKUP

Where YEAR is a four-digit number, MONTH and DAY are both two-digit numbers, and MARKUP is the file extension representing the format used in the file. For example, the following are examples of valid post filenames:

2011-12-31-new-years-eve-is-awesome.md
2012-09-12-how-to-write-a-blog.textile
ProTip™: Link to other posts

Use the post_url tag to link to other posts without having to worry about the URL's breaking when the site permalink style changes.

Content Formats

All blog post files must begin with YAML Front Matter. After that, it’s simply a matter of deciding which format you prefer. Jekyll supports Markdown out of the box, and has myriad extensions for other formats as well, including the popular Textile format. These formats each have their own way of marking up different types of content within a post, so you should familiarize yourself with these formats and decide which one best suits your needs.

Be aware of character sets

Content processors can modify certain characters to make them look nicer. For example, the smart extension in Redcarpet converts standard, ASCII quotation characters to curly, Unicode ones. In order for the browser to display those characters properly, define the charset meta value by including <meta charset="utf-8"> in the <head> of your layout.

Including images and resources

Chances are, at some point, you’ll want to include images, downloads, or other digital assets along with your text content. While the syntax for linking to these resources differs between Markdown and Textile, the problem of working out where to store these files in your site is something everyone will face.

Because of Jekyll’s flexibility, there are many solutions to how to do this. One common solution is to create a folder in the root of the project directory called something like assets or downloads, into which any images, downloads or other resources are placed. Then, from within any post, they can be linked to using the site’s root as the path for the asset to include. Again, this will depend on the way your site’s (sub)domain and path are configured, but here some examples (in Markdown) of how you could do this using the site.url variable in a post.

Including an image asset in a post:

... which is shown in the screenshot below:
![My helpful screenshot]({{ site.url }}/assets/screenshot.jpg)

Linking to a PDF for readers to download:

... you can [get the PDF]({{ site.url }}/assets/mydoc.pdf) directly.
ProTip™: Link using just the site root URL

You can skip the {{ site.url }} variable if you know your site will only ever be displayed at the root URL of your domain. In this case you can reference assets directly with just /path/file.jpg.

Displaying an index of posts

It’s all well and good to have posts in a folder, but a blog is no use unless you have a list of posts somewhere. Creating an index of posts on another page (or in a template) is easy, thanks to the Liquid template language and its tags. Here’s a basic example of how to create a list of links to your blog posts:

<ul>
  {% for post in site.posts %}
    <li>
      <a href="{{ post.url }}">{{ post.title }}</a>
    </li>
  {% endfor %}
</ul>

Of course, you have full control over how (and where) you display your posts, and how you structure your site. You should read more about how templates work with Jekyll if you want to know more.

Note that the post variable only exists inside the for loop above. If you wish to access the currently-rendering page/posts’s variables (the variables of the post/page that has the for loop in it), use the page variable instead.

Post excerpts

Each post automatically takes the first block of text, from the beginning of the content to the first occurrence of excerpt_separator, and sets it as the post.excerpt. Take the above example of an index of posts. Perhaps you want to include a little hint about the post’s content by adding the first paragraph of each of your posts:

<ul>
  {% for post in site.posts %}
    <li>
      <a href="{{ post.url }}">{{ post.title }}</a>
      {{ post.excerpt }}
    </li>
  {% endfor %}
</ul>

Because Jekyll grabs the first paragraph you will not need to wrap the excerpt in p tags, which is already done for you. These tags can be removed with the following if you’d prefer:

{{ post.excerpt | remove: '<p>' | remove: '</p>' }}

If you don’t like the automatically-generated post excerpt, it can be explicitly overridden by adding an excerpt value to your post’s YAML Front Matter. Alternatively, you can choose to define a custom excerpt_separator in the post’s YAML front matter:

---
excerpt_separator: <!--more-->
---

Excerpt
<!--more-->
Out-of-excerpt

You can also set the excerpt_separator globally in your _config.yml configuration file.

Completely disable excerpts by setting your excerpt_separator to "".

Also, as with any output generated by Liquid tags, you can pass the | strip_html filter to remove any html tags in the output. This is particularly helpful if you wish to output a post excerpt as a meta="description" tag within the post head, or anywhere else having html tags along with the content is not desirable.

Highlighting code snippets

Jekyll also has built-in support for syntax highlighting of code snippets using either Pygments or Rouge, and including a code snippet in any post is easy. Just use the dedicated Liquid tag as follows:

{% highlight ruby %}
def show
  @widget = Widget(params[:id])
  respond_to do |format|
    format.html # show.html.erb
    format.json { render json: @widget }
  end
end
{% endhighlight %}

And the output will look like this:

def show
  @widget = Widget(params[:id])
  respond_to do |format|
    format.html # show.html.erb
    format.json { render json: @widget }
  end
end
ProTip™: Show line numbers

You can make code snippets include line-numbers by adding the word linenos to the end of the opening highlight tag like this: {% highlight ruby linenos %}.

These basics should be enough to get you started writing your first posts. When you’re ready to dig into what else is possible, you might be interested in doing things like customizing post permalinks or using custom variables in your posts and elsewhere on your site.