A simple static site generator in Python

What is a static site generator?

A static site generator is a bit of code which takes input files, for instance from Markdown files or from another source on the web, and builds a website from it. For it to be static, the website is usually just plain HTML. Static site generators are handy because they remove a lot of the complexity of using a server based site such as Wordpress or a custom Django blog, and instead let you just focus on the content. They are better than traditional HTML web pages because they let you apply templates to style your HTML pages just like any other server based site.

When I needed to make a manual for the data acquisition system I have been building, I decided I wanted to write the content in Markdown and use a static site generator to build the web pages for me. These pages (when ready) can then be dropped onto a web server or github pages.

Why make my own?

I've used Pelican on a number of sites including the one you are browsing at the minute, and have found it to be pretty good. Yet as the software matures they are splintering the code base, putting plugins in one repository, themes in another and the core site generator in a third. This means I have to install and maintain three different repositories and bits of software on my computer to generate a static site. This is a pain. It also means that since I got it working on my Linux install and haven't really been bothered to get it working on my Windows machine, every time I want to update the site I have to reboot into Linux.

So for the manual I looked around and there are a lot of different site generator options - over 230 to be exact. A lot of the more popular ones have all the bells and whistles, plugins, command line tools, test servers, different input formats, you name it. At the end of the day all I want to do is to take a bunch of Markdown files, convert them into HTML and spit out a website with the same directory structure as my input files. Rather than download 230 tools until I found one that worked I just decided to bake my own.

How it works

The source code is available (MIT licensed) in this gist or on my website

The generator uses Jinja2 for templates and Markdown2 for rendering Markdown. It uses the metadata Markdown extra so that you can specify the template and any context variables for the template in your Markdown. A Markdown document with metadata could look like:

---
title: My cool article
keywords: article, cool, my, python, ftw
template: index.html
---

# This is a Markdown document

There are many like it but this is mine

Thats it - normal Markdown for the most part. If you don't specify a template in the metadata then index.html will be used and if you haven't got an index.html in your templates folder the script gives up and dies. The generator relies on a set directory structure:

root
 |----src
 |     |---- # your markdown files in here in any directory structure you like
 | 
 |----templates
 |     |---- # your Jinja2 templates go here
 |     |----static
 |     |    |---- # CSS files, javascript, etc go in the static folder

When you run the generator it converts all the Markdown files in the src directory into HTML, applies the correct template from the templates folder and puts it all in the output folder. It copies the static directory to build as well so you have your CSS and javascript.

This approach makes it really easy to link between files or insert images. All you have to do is write the Markdown as you normally would. I add an images folder to the src folder and throw all my images in there. By setting the STATIC_DIRS variable in the script I can ensure the images get copied over to the build directory.

To build a site, assuming you have downloaded the script as build.py you just run

$ python build.py