How to know if an URL is relative or absolute in Jekyll?

Question

I'm trying to do the following in Jekyll:

• I have an URL;

• This URL can be relative ("/media/image.jpg") or absolute "http://example.com/image.jpg";

• If the URL is relative I have to append to its beginning my site domain ("http://my-site/media/image.jpg"). If don't, nothing changes.

Sadly I have no clue yet on how to achieve this.

I'd love if somebody could help me.

Thanks in advance.

Answer 1

You can do this using liquid. Here is a basic example of what you could do. You will probably want to adjust it for your own use.

{% assign myurl = "/css/bootstrap.min.css" %}
{% if myurl contains '://' %}
{{myurl}}
{% else %}
{{ myurl | prepend: site.url }}
{% endif %}

Breaking down the code:

This line just creates a variable holding the url:

{% assign myurl = "/css/bootstrap.min.css" %}

Next, we will check if the url is absolute. This simple version does that by checking the string, ://, is in the url:

{% if myurl contains '://' %}

If the url does, liquid will simply print out the url variable:

{{myurl}}

If not, liquid will prepend the site's url to the beginning of url and print the complete url:

{% else %}
{{ myurl | prepend: site.url }}
{% endif %}