How I fixed the unknown language Pygments error in Octopress

3 minute read

Last time I tried to insert a code snippet in my Octopress blog, I was hurt by the following error :

vagrant@ae4a04cebb73:/vagrant$ bundle exec rake generate
## Generating Site with Jekyll
unchanged sass/screen.scss
Configuration from /vagrant/_config.yml
Building site: source -> public
/vagrant/plugins/pygments_code.rb:27:in `rescue in pygments': Pygments can't parse unknown language: ruby. (RuntimeError)
	from /vagrant/plugins/pygments_code.rb:24:in `pygments'
	from /vagrant/plugins/pygments_code.rb:14:in `highlight'
	from /vagrant/plugins/backtick_code_block.rb:37:in `block in render_code_block'
	from /vagrant/plugins/backtick_code_block.rb:13:in `gsub'
	from /vagrant/plugins/backtick_code_block.rb:13:in `render_code_block'
	from /vagrant/plugins/octopress_filters.rb:12:in `pre_filter'
	from /vagrant/plugins/octopress_filters.rb:28:in `pre_render'
	from /vagrant/plugins/post_filters.rb:112:in `block in pre_render'
	from /vagrant/plugins/post_filters.rb:111:in `each'
	from /vagrant/plugins/post_filters.rb:111:in `pre_render'
	from /vagrant/plugins/post_filters.rb:166:in `do_layout'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/lib/jekyll/post.rb:195:in `render'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/lib/jekyll/site.rb:200:in `block in render'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/lib/jekyll/site.rb:199:in `each'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/lib/jekyll/site.rb:199:in `render'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/lib/jekyll/site.rb:41:in `process'
	from /vagrant/vendor/bundle/gems/jekyll-0.12.1/bin/jekyll:264:in `<top (required)>'
	from /vagrant/vendor/bundle/bin/jekyll:22:in `load'
	from /vagrant/vendor/bundle/bin/jekyll:22:in `<main>'

I had been switching to Docker in Vagrant to host my Octopress installation, but that did not seem related …

Plan A : Upgrade Octopress

It turned out it was related to my migration to Vagrant and Docker.xs This kind of nasty error often comes from obsolete environment. Internet confirmed confirmed it :

  • Ubuntu now uses Python3 instead of Python2
  • Octopress2 uses an old version of Pygments
  • That version of Pygments requires Python2

I thought that I did not want to play this game against open source libs, so I set out to update. Octopress 3 has been released. It’s not yet documented yet, and there is no official upgrade guide, but some guys have done it :


I tried it … but I stopped before the end. It’s kind of working, but fundamental features like category archives required too much Jekylling for me at the time. And themes are still an issue … I mean, stock theme uses a clean and simple gem based update workflow, but most other themes rely on a tricky git clone-merge update workflow.

Plan B : Find a hosted blog engine for hackers

I found quite a few options :

  • Medium Looks cool, but there is no simple migration tool, and I’ve been burned by shutting down, I want to keep control on my content
  • Posthaven Having loved, this one seems cool, It’s just I’m not sure the guys are keeping the motivation to increase their feature list with their current business model
  • Ghost Looked great, but too expensive for me (19$ per month)
  • Codrspace This is a special blogging platform for coders, but it seems it has not been updated for a long time
  • LogDown This also is a special blogging platform for hackers. It seemed great and had everything I was looking for … I was ready to spend the 50$ per year for it as it could save me a lot of hassle. Unfortunately, I could not find a way to forward the categories of a post as Twitter hashtags as I’ve been doing with Octopress and Feedburner

In the end, I was rather disappointed by the alternatives, even though I was ready to pay for them.

Plan C : Fix the error in Octopress 2

Eventually, the fix was rather easy. People had fixed it by patching file in the pygments.rb gem to run Python 2 instead of the stock Python. That’s not great because it means that I’d have to redo the patch every time I updated my gems, or rebuilt my workspace. Here is what I added to my Vagrantfile instead :

sudo apt-get -y install python2.7
sudo ln -sf /usr/bin/python2.7 /usr/bin/python

Here is the commit on my Github repo.


I’m sticking with Octopress2 for the moment. Maybe I’ll re-try to migrate to Octopress3 later on, when an official migration tool or guide is available. Meanwhile, I’m still dreaming of my perfect blogging platform :

  • Open source
  • Static HTML generation
  • Self or SAAS hosted
  • Great integration with social media and the web
  • Easy to maintain
  • Plugable themes

I’m looking for my next side project at the moment, that could be a useful one ! Anyone interested ?

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