tags-vs-categories in Pelican

So, following up on my transition to pelican, here's a little help for navigating a pelican site. If you've ever wondered why sometimes there's a highlighted menu item at the top, and other times there isn't, read on.

Categories

With Pelican, every post belongs to exactly one category - that category is 'misc' if one is not provided (and you can override that named by setting DEFAULT_CATEGORY = 'somethingelse' in your pelicanconf.py file). Alternatively, if the post is in a subdirectory, it's category becomes the subdirectory name. So if you have a situation like this:

.../content/unicorns/lady-rainicorn.md

The lady-rainicorn post will be filed under the category of unicorns. You can explicitly override this category-from-subdirectory behavior, by specifying the category in the header of the file, like so:

title: All about Lady Rainicorn
slug: lady-rainicorn
category: adventure-time

Categories are where a lot of the pelican themes get the top navigation bar, which is referred to as the menu in Pelican. You'll notice that this post is filed under technology. If you're viewing this on the main page, that won't be highlighted, but if you click on the title of this post, you'll see that technology will become highlighted. Same deal if you just click on technology, which will get you a listing of the latest post in that category, and a pagination of all previous ones.

Pages

The menu items need not be limited to categories, however. With the popular notmyidea template (which is what I've customized for my journal here), if you create any pages (by putting the file in a content/pages/ directory), then the title of that page will appear in front of all of the categories in the menu. These pages don't show up in RSS feeds, though.

Menuitems

Additionally, you can specify other MENUITEMS in pelicanconf.py, which will go in front of all pages and categories. MENUITEMS is a list of tuples, each tuple should be composed of a link name, and a url. This is how I link to the listing of all of my blog posts:

MENUITEMS = [('all', '/blog/archives.html')]

Tags

Finally, you can have zero or more tags attached to a post. Tags, by default, do not get a feed generated for them. To enable a tag feed, you'll have to set a line like this in your pelicanconf.py files:

TAG_FEED_ATOM = "feeds/tag_%s.atom.xml"

Menu highlighting

The notmyidea template only contains logic for highlighting the active category. This is why, if you click on 'All' at the top of mine, it doesn't stay highlighted when you're on that page.

On the other hand, if you click at cycling at the menu bar, it will stay highlighted, and you will see a listing of the articles in that category. But if you click on the cycling tag in one of those posts - the menu item will not be highlighted, and you will see some more articles - in particular, right now my review of Just Ride will also be listed, but it lives in the category of books, because that's where I'm keeping book reviews.

Summary

So there you have it - now you know the differences between categories, tags, pages, and menu items, as far as Pelican is concerned. For me, the bottom line is that I'll probably stick to just using categories, and will try to use tags sparingly. In my transition from WordPress, I cleaned up and removed a whole bunch of tags (since they were either redundant (the same tags kept appearing together), or were too specific (most tags were only used for one post).

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