Practical OSS: MkDocs for the IBM i, Part 1

Linux / Open Source
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MkDocs may be the shortest path from tribal knowledge to IT portal.

During my continuing foray into open-source software (OSS), I ran across a very interesting tool named MkDocs. Richard Schoen mentioned it on the Midrange mailing lists. I was a little concerned—not because it was open source, but because it used the dreaded Python language. Personally, I’ll program in any language; I wrote a lot of Lisp back in the ‘80s when it was the primary language for programmable synthesizers. But Python and its reliance on the number of spaces at the beginning of a line of code has always given me the heebie-jeebies. That being said, the concept of MkDocs became more intriguing the more I read, and it seemed like I wouldn’t really have to learn much about Python to make it work. (Yeah, that was wrong, but still.)

So this is the first of a brief series of articles that will introduce the MkDocs utility and hopefully make you as curious about it as I was and perhaps lead you to incorporate it in your own shop.

What Is MkDocs?

For in-depth information, you can go to the MkDocs website to find out about the package. In brief, it’s a tool that takes very simple text files and turns them into a beautifully rendered website, complete with navigation and search capabilities. The generic term for this kind of tool is “static site generator” because its purpose is to create static HTML that can then be copied very simply to any web server. On the IBM i, I just copy everything to an Apache web instance (with a single command) and off it goes.

But calling MkDocs just a static site generator is an understatement. Yes, you can use it just to render text into HTML, but there is so much more to it; MkDocs is a powerful, highly extensible ecosystem of features and functions that allows you to customize your website in a wide variety of ways. But let’s start with the basics.

First, MkDocs is based on the Markdown language created by Jon Gruber in 2004. At its simplest, Markdown is a text-based editor, as opposed to a WYSIWYG editor. You write your content in simple, mostly unformatted text documents. Certain basic functions are understood, such as headings and highlighting, but they’re triggered by characters within the text itself. For example, the main heading for a page is on a line by itself that starts with a single hashtag (#). Second-level headings start with two hashtags (##) and so on. One of the things I really like about Markdown is that it’s geared toward technical writing and as such supports the concept of a “fenced code block.” These code blocks start and end with three backticks (```). This triggers the Markdown processor to highlight the block using monospaced code, typically with the ability to copy the code with a single click. I’ll show this in more detail in subsequent articles that will focus on a real example.

But for this article, let’s continue with some of the high-level concepts. Foremost would be the idea of a theme. Themes are an integral part of Markdown and thus of MkDocs. MkDocs creates static websites that make extensive use of CSS, and the CSS is part of the theme. By simply changing a single line in your configuration, you can completely change the visual feel of your site. Hundreds of themes are out there for your choosing; click here for a site with five examples. I like this site because it includes the theme I’m currently using, Material for MkDocs. But CSS is only one component of a theme. Remember that MkDocs generates HTML. That generation isn’t hardcoded; it uses templates that are populated and combined to form pages. Once you really start getting into MkDocs, you may find yourself customizing the templates to add your own specific touches.

After templates, the two other big components are extensions and plug-ins. We’ll cover these in more detail in the next article, but basically these are two ways to provide additional functionality, not unlike extensions for your favorite web browser.

What Is Required to Use MkDocs?

Short answer: not much. The very high-level setup steps are:

  • Make sure you have the IBM i Open Source Package Management (OSPM) installed.
  • Install mkdocs.
  • Install material theme (highly recommended).
  • Create a basic Apache web server instance.

At this point, you’ve done everything you need to develop your website. I recommend creating a folder named mkdocs in the root of your IFS (or one level down if you have a sandbox area already). Add a subfolder for your test website and get cracking!

  • Run mkdocs serve and get your site working.
  • Run mkdocs build to generate the HTML in folder
  • Copy it to your Apache instance’s base folder.

That’s it. But there’s always a little more to it, isn’t there? Let me elaborate.

Detailed Startup Steps

The first thing in setup is getting the IBM i Open Source Package Management installed. This is a little bit in the weeds, but the short version is that the 5733-OPS licensed product is pretty much superseded by the IBM i Open Source Package Management. Click here for the IBM take on OSPM and installing the latest version via IBM i ACS. For more in-depth discussion from the user community, go to the IBM i OSS Docs site.

As part of the ACS installation of OSPM, you should automatically get Python3. That’s important, because everything we’re doing really requires the new version of python. And once you have Python3 installed, you can then use pip3 to install some of the additional pieces that will make your website even better. Please note that you don’t need these additional features, but they make life a lot more fun, and pip3 is super easy to use. Caveat: Like everything in open source, the happy path is very easy. The problem is that when things don’t work, it’s hard to figure it out. Because I didn’t understand the correct sequence of things, I ran into some problems that required me to learn way more about Python, pip, and package management than I had intended to.

Anyway, once you’ve done that, you can install MkDocs. Richard Schoen has done a great job of documenting this process on his howtostuff site. It was Richard’s initial enthusiasm that got me started down this path, so if you enjoy MkDocs, thank him. Then you can use pip3 to install the Material theme. Please be careful and use pip3 rather than pip. I am not going to go into a discussion of Python virtual environments where you can alias Python to Python3 and pip to pip3. Just remember that when you install a piece of Python software, use pip3 wherever you see pip.

I won’t spend a lot of time on creating an Apache web server. If you want in-depth documentation, you can use the IBM documentation. Generally speaking, you need the simplest configuration of a web server, because all it does is serve up web pages. I recommend you create a folder /www/mkdocs, and put a subfolder under there for each website you plan to create. I basically just have a test folder and a production folder, but you may find it so easy to create web sites that you create multiple.

Even More Fun in Testing

If (like me) you find things not working on the IBM i and you need another way to check your work, or if you just want to get deeper into the UNIX side of things, you can run this entire process in Linux. And what’s really cool is that if you have Windows 10, you can run Linux right on your Windows desktop using Windows Subsystem for Linux (WSL). That’s way outside the scope of this article, but if you want a very solid Linux playground that doesn’t require virtual machines or anything else, please check into it. Installing WSL took me about an hour, and it gave me a fantastic place to work. I now have an icon on my taskbar that I click to bring up an Ubuntu instance. If you want to start honing your Linux skills, then by all means get this running.

A Little Research Note

As I was researching text-processing software, I ran across a wonderful little tidbit. If you’re as old as I am, you remember the days before Microsoft Word. One of my very first jobs was to program an interface between the IBM Series/1 (not the iSeries!) and dedicated word processors from Ontel. If you’d like to see an interesting little bit of history, please take a look at_”A Brief History of Word Processing,” written back in 1986 by Brian Kunde. Enjoy!